Animal Research

Animal research case studies


UCL is a leading centre for biomedical research in the UK. Scientific research is conducted not by shadowy figures in ivory towers, but by human beings working earnestly to address major issues facing society today.

UCL research mouse

Dr Clare Stanford: using mice to find treatments for ADHD

Dr Clare Stanford is a Reader in Experimental Psychopharmacology at UCL. Despite the intimidating title, Clare is a down-to-earth, compassionate researcher with a real commitment to animal welfare. She is chair of the Bloomsbury AWERB and does not hold back from questioning the ethics of research objectives , as well as the way it is carried out.

Clare is currently working on a mouse model for Attention Deficit Hyperactivity Disorder (ADHD). This is a strongly inherited psychiatric disorder, which causes problems for patients by making them hyperactive, excessively impulsive and inattentive. ADHD is often regarded as a childhood issue, but about 65% of people carry it through to adulthood where the associated problems are far worse. It has been associated with alcohol and drug misuse in later life, and an estimated 25% of the prison population have ADHD . There is also an increased risk of other health complications, including asthma and epilepsy.

Picture of 10-day old mice. The glowing mice had firefly genes injected into their brains at birth, designed to respond to different molecular processes important for cell development. The glow is not visible to the naked eye, so the image was taken…

Dr Simon Waddington and Rajvinder Karda: reducing mouse use with glowing firefly genes

Although animal research remains a necessary part of modern research, current methods are far from perfect. By injecting the genes that fireflies use to emit light into newborn mice, UCL scientists have developed a way to drastically reduce the numbers of mice needed for research into disease and development.

At the moment, researchers often need to cull and perform autopsies on animals to see how diseases develop on a molecular level. This means that an animal needs to be killed for every data point recorded, so some studies might use dozens of mice to get reliable data on disease progression.

The new technique could allow researchers to get molecular-level data by simply taking a picture with specialist equipment rather than killing an animal, allowing them to get data more regularly and ethically. An experiment that previously need 60 mice can be done with around 15, and the results are more reliable.


Dr Karin Tuschl: Using zebrafish to treat a rare form of childhood Parkinsonism

Using genetically modified zebrafish, UCL scientists have identified a novel gene affected in a devastating disorder with childhood-onset Parkinsonism. Indeed, when a drug that worked in the fish was given to one of the children, she regained the ability to walk.

The research studied a group of nine children who suffered from severely disabling neurological symptoms including difficulties in walking and talking. Dr Karin Tuschl and her team at the UCL Great Ormond Street Institute of Child Health and UCL Department of Cell and Developmental Biology used state of the art genome editing in zebrafish to validate the identity of the gene affected in these children.

The scientists disrupted a gene known as slc39a14 in the fish, which is important for transporting metals in the body. Disrupting the transporter in fish led to a build up of manganese in the brain and impaired motor behaviour. As similar symptoms were seen in the patients, this confirmed that slc39A14 is required to clear manganese from the body and protect it from manganese toxicity. It also confirmed that the scientists had found the gene causing the disease in the patients.

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Use of Animals in Research - Case Studies

As part of our commitment to the concordat on openness on the use of animals in research, here are some short articles explaining how and why we use animals in research at the RVC.

  • Acromegaly in Cats
  • Diabetic Remission Clinic
  • Ragdoll cats study
  • A study to establish canine and feline 95% reference intervals for the QMHA Radiometer ABL800 FLEX machines
  • Oesophageal feeding tube placement study : using cats and dogs
  • Dogs and Research at the RVC
  • Canine Epilepsy Research
  • Duchenne Muscular Dystrophy
  • Mitral Valve Disease
  • Nausea Research and Dogs

Guinea Pigs

  • Developing a treatment for foetal growth restriction
  • Gait Analysis
  • Stem Cell Based Treatments
  • Summary of Recent Laminitis Research at the RVC
  • Recurrent Laryngeal Neuropathy
  • Immunobiology of fertility in mares
  • The Regulation of Soft Tissue and Skeletal Calcification
  • Muscular dystrophy research using the mdx mouse
  • FSTL3: A Crucial Regulator of Sertoli Cell Proliferation
  • Mechanical loading and Genetic susceptibility to Osteoarthritis
  • Sheep models for regenerative medicine
  • How to grow new blood vessels: the zebrafish as a model to study angiogenesis in development and regeneration
  • Use of zebrafish to increase our understanding of diseases

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The Case for Animals in Research and Teaching

Animal research and use.

At the University of Massachusetts Amherst, research is conducted with respect to a wide range of health concerns. In certain cases, it is necessary to use laboratory animals in studies to advance science and achieve breakthroughs that improve human and animal health and save lives. In fact, all research institutions around the globe rely heavily on the use of animals in health research. We are committed to humane, responsible, and ethical treatment of all animals, including abiding by all relevant federal and Massachusetts regulations and requirements.

Why Animal Research?

Animals are used in research only when no better options exist. Over the past two decades, significant progress has been made in developing alternatives such as cell cultures and computer models, yet there are still cases in which research involving animals is necessary to study the complex interactions of different physiological processes and systems. In these situations, animal models can help by mimicking the human disease, defect, or ailment in order to allow for therapeutic research. The use of laboratory animals is vital to research conducted in many fields, including immunology, neuroscience, behavior, nutrition, and conservation research in field settings. For example, at UMass Amherst, animal research is leading to improved understanding of breast cancer susceptibility factors, effects of age on cognitive abilities, women’s health, the effects of certain chemical on human health, and the impact of shift work on the circadian clock as it relates to metabolism and various diseases. In some cases, animal research leads to discoveries that improve the health and well-being of animals, such as research into contraception in feral animals.

Our Commitment to Animal Care

We follow the highest ethical standards and all applicable laws in our policies and practices relating to laboratory animals. All researchers must go through a rigorous process to justify the use of animals in research, including demonstrating that there are no viable alternatives. The Institutional Animal Care and Use Committee (IACUC) reviews all research and teaching studies involving living, non-human vertebrate animals to ensure humane care and use.

The Attending Veterinarian/Director of Animal Care Services oversees the care of animals, with additional oversight from the IACUC. To promote the animals’ health and comfort, our facilities are regulated for heat, air conditioning, ventilation, humidity, lighting, and access, and are located close to classrooms and laboratories to minimize transportation stress. Facilities are cleaned and checked on a regular schedule in compliance with federal animal welfare laws. Animal Care staff feed, water, and check the animals’ health and well-being every day, year-round. In addition, animals benefit from environmental enrichment, such as toys and treats.

For more information on animal research programs, protocols, and oversight, please visit the Animal Subjects FAQ .

External Resources:

  • Nonhuman Primate Models in Biomedical Research: State of the Science and Future Needs | The National Academies Press
  • Animals in NIH Research
  • Professor Agnès Lacreuse in The Conversation : “Expanding Alzheimer’s Research with Primates Could Overcome the Problem with Treatments that Show Promise in Mice but Don’t Help Humans”
  • Americans for Medical Progress
  • American Veterinary Medical Association
  • The AALAS Foundation  
  • The American Physiological Society
  • Federation of American Societies For Experimental Biology
  • Foundation for Biomedical Research
  • Massachusetts Society for Medical Research
  • National Primate Research Centers
  • Society for Neuroscience
  • Research!America
  • Speaking of Research
  • States United for Biomedical Research
  • Understanding Animal Research 
  • NIH Guidance on Institutional Animal Care and Use Committees

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Animal research case studies

Explore some case studies from our research involving animals at Sussex.

Examples of our case studies

In this section we have included some examples of research involving animals which have been undertaken at the University of Sussex.

There is one study which does not fall under the Animals (Scientific Procedures) Act (1986) (also referred to as ASPA). This is an observational study, investigating whether or not African Elephants have culture. Although this study is not regulated in the same way as studies which fall under the Act, the AWERB aspires to undertake ethical review of all studies involving animals undertaken by staff or students at the University of Sussex.

Colorful zebra fish on a bluye background

Visual processing in fish

Multimillion pound grant awarded to Sussex neuroscientist to investigate visual processing in fish.

Two mice at different points in a maze

Understanding Alzheimer's disease

This study of mice is useful in the search for preventive measures and treatments for Alzheimer's disease.

Three elephants in a close shot, one laying down and two walking at a distance

Elephant communication and cognition

Learn about the cognitive abilities of African elephants and how they exhibit extensive social knowledge. 

Three mice in a container

Ethical considerations involving animal research at Sussex.

We are committed to meeting all ethical and regulatory requirements for research involving animals. 

This page has been archived and is no longer updated

Saving Endangered Species: A Case Study Using Global Amphibian Declines

case studies animal research

How are Endangered Species Identified?

The International Union for Conservation of Nature and Natural Resources (IUCN) Red List uses a hierarchical structure of nine categories for assigning threat levels for each species or subspecies. These categories range from 'Extinct' to 'Least Concern' (Figure 1). At the highest levels of threat, taxa are listed as 'Critically Endangered,' 'Endangered,' or 'Vulnerable,' all of which are given 'Threatened' status. A series of quantitative criteria is measured for inclusion in these categories, including: reduction in population size, geographic range size and occupancy of area, total population size, and probability of extinction. The evaluation of these criteria includes analyses regarding the number of mature individuals, generation time, and population fragmentation. Each taxon is appraised using all criteria. However, since not all criteria are appropriate for assessing all taxa, satisfying any one criterion qualifies listing at that designated threat level.

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There are a variety of human activities that contribute to species becoming threatened, including habitat destruction, fragmentation, and degradation, pollution, introduction of non-native species, disease, climate change, and over-exploitation. In many cases, multiple causes act in concert to threaten populations. Though the causes underlying population declines are numerous, some traits serve as predictors of whether species are likely to be more vulnerable to the causes listed. For example, many species that have become endangered exhibit large body size, specialized diet and/or habitat requirements, small population size, low reproductive output, limited geographic distribution, and great economic value (McKinney 1997).

How to Save Endangered Species

There are a variety of methods currently being implemented to save endangered species. The most common are creation of protected areas, captive breeding and reintroduction, conservation legislation, and increased public awareness.

Protected areas

An effective and internationally recognized strategy for conserving species and ecosystems is to designate protected areas. The United Nations Environment Programme World Conservation Monitoring Center (UNEP-WCMC) defines a protected area as "an area of land and/or sea especially dedicated to the protection of biological diversity and of natural and associated cultural resources, managed through legal or other effective means." Worldwide, extensive systems of protected areas have been developed and include national parks, state/provincial parks, wildlife refuges, and nature reserves, all of which differ in their management objectives and degree of protection. The IUCN has defined six protected area management categories, based on primary management objective (Table 1). These categories are defined in detail in the Guidelines for Protected Areas Management Categories published by IUCN in 1994.

The World Database on Protected Areas (WDPA) records all nationally designated terrestrial and marine protected areas whose extent is known. These data are collected from national and regional governing bodies and non-governmental organizations. Currently, there are over 120,000 protected areas (2008 estimate, UNEP-WCMC), covering about 21 million square kilometers of land and sea. Since 1872, there has been a dramatic increase in the global number and extent of nationally designated protected areas (Figure 2). Well-planned and -managed protected areas not only benefit species at risk, but other species associated with them, thereby increasing the overall amount of biodiversity conserved. Despite increases in the size and number of protected areas, however, the overall area constitutes a small percentage of the earth's surface. Because these areas are critical to the conservation of biodiversity, the designation of more areas for protection and increases in the sizes of those areas already in existence are necessary.

Another opportunity for creating protected areas is the Alliance for Zero Extinction (AZE), an international consortium of conservation organizations that specifically targets protection of key sites that represent sanctuaries of one or more Endangered or Critically Endangered species. The AZE focuses on species whose habitats have been degraded or whose ranges are exceptionally small, making them susceptible to outside threats. Three criteria must be met in order to prioritize a site for protection (Table 2). To date, 588 sites encompassing 920 threatened species of mammals, birds, reptiles, amphibians, conifers and corals have been identified. The goal of such efforts is to prevent the most imminent species extinctions by increasing global awareness of these key areas.

Captive breeding and reintroduction

Some species in danger of extinction in the wild are brought into captivity to either safeguard against imminent extinction or to increase population numbers. The primary goals of captive breeding programs are to establish populations via controlled breeding that are: a) large enough to be demographically stable; and b) genetically healthy (Ebenhard 1995). These objectives ensure that populations will exhibit a healthy age structure, resistance to disease, consistent reproduction, and preservation of the gene pool to minimize and/or avoid problems associated with inbreeding. Successful captive breeding programs include those for the Guam rail, scimitar-horned oryx, and Przewalski's horse. (See iucnredlist.org for details.)

Establishing captive populations is an important contribution of zoos and aquariums to the conservation of endangered species. Zoos and aquariums have limited space, however, so to maintain healthy populations, they cooperate in managing their collections as breeding populations from international to regional levels. The World Association of Zoos and Aquariums (WAZA) is the organization that unites the world's zoos and aquariums in cooperative breeding programs. Perhaps the most important tools in managing these programs are studbooks, which ensure that captive populations maintain a sufficient size, demographic stability, and ample genetic diversity. All information pertinent to management of the species in question is included (e.g., animal registration number, birth date, parentage, behavioral traits that may affect breeding). These studbooks are used to make recommendations regarding which individuals should be bred, how often, and with whom in order to minimize inbreeding and, thus, enhance the demographic and genetic security of the captive population.

Another goal of some captive breeding programs is to reintroduce animals to the wild to reestablish populations. Examples of successful introductions using captive-bred stock include California condors (Ralls & Ballou 2004) and black-footed ferrets (Russell et al. 1994). Reintroductions can also utilize individuals from healthy wild populations, meaning individuals that are thriving in one part of the range are introduced to an area where the species was extirpated. Reintroduction programs involve the release of individuals back into portions of their historic range, where they are monitored and either roam freely (e.g., gray wolves released in Yellowstone National Park) or are contained within an enclosed area (e.g., elk in Land Between the Lakes National Recreation Area in western Kentucky; Figure 3). However, reintroduction is only feasible if survival can be assured. Biologists must ascertain whether: a) the original threats persist and/or can be mitigated; and b) sufficient habitat remains, or else survival will be low upon release.

Laws and regulations

Biodiversity is protected by laws at state/provincial, national, and international levels. Arguably the most influential law is the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) which is an agreement between governments (i.e., countries) that controls international trade in wild animals, plants, and their parts to ensure continued survival. International trade in wildlife is a multi-billion dollar industry that affects millions of plants and animals. As a result, CITES lists species in three Appendices according to the level of protection they require to avoid over-exploitation; species listed in Appendix I require the most protection and, thus, trade limitations (Table 3). Currently, approximately 30,000 species are protected under CITES (Table 4).

The trade in wildlife is an international issue and, as such, cooperation between countries is required to regulate trade under CITES. However, member countries adhere to regulations voluntarily and, consequently, they must implement them. Most important, CITES does not take the place of national laws; member countries must also have their own domestic legislation in place to execute the Convention.

Public awareness

In general, the public is unaware about the current extinction crisis. Public awareness can be increased through education and citizen science programs. Conservation education often begins in elementary school and may be enhanced through summer camps or family vacations that are nature oriented (e.g., involve visiting national or state parks). Early positive experiences with nature are essential for children to gain an appreciation for wildlife and the problems species face. In high school, this education is continued through formal science education and extra-curricular activities. Other means of increasing public awareness involve internet websites where subscribers can receive emails from conservation organizations like Defenders of Wildlife, Environmental Defense, and World Wildlife Fund. In many cases, these organizations provide updates on the status of endangered species and promote letter writing to elected officials in requesting protection for endangered species and their habitats.

CASE STUDY IN CONSERVATION: Global declines in amphibian populations

Amphibians are one of the earth's most imperiled vertebrate groups, with approximately one-third of all species facing extinction (Stuart et al . 2004). Causes of amphibian population declines and extinctions echo those listed in the introductory paragraphs but primarily consist of drainage and development of wetland habitats and surrounding uplands, contamination of aquatic habitats, predation by or hybridization with introduced species, climate change, and over-harvesting (Collins & Storfer 2003). In addition, the recent declines observed in relatively pristine areas, such as state, provincial, and national parks worldwide have brought to light the tremendous impact of pathogens on amphibian populations, most notably that of the amphibian-killing fungus Batrachochytrium dendrobatidis (Bd). So what is being done to preserve amphibian diversity?

To address the historic sources of amphibian population declines, such as overexploitation and habitat loss, national and international legislation exists to monitor the trade in amphibians and prevent further reductions in available habitat. Although international trade in amphibians is less common relative to trade in other vertebrate groups, CITES currently lists 131 species in Appendices I-III. Furthermore, IUCN currently lists 509, 767, and 657 amphibian species as Critically Endangered, Endangered, or Vulnerable (Figure 4), respectively. These species' native habitats are afforded protection at various levels of organization. The AZE has identified 588 sites worldwide exhibiting at least one criterion for protection (Table 2), and these sites are home to hundreds of amphibian species listed by IUCN as between Vulnerable and Critically Endangered. In addition, IUCN's Amphibian Specialist Group (ASG) has partnered with governmental and non-governmental organizations and individuals to create new protected areas and minimize further population declines due to habitat fragmentation and loss. In addition to designation of new protected areas, efforts of the ASG include habitat restoration, promotion of ecotourism, and extended amphibian-monitoring programs.

Despite efforts to preserve suitable habitat, biologists became increasingly aware of catastrophic population declines associated with Bd, and more urgent action became necessary when declines were detected in protected areas with minimal risks of habitat loss and overexploitation. Batrachochytrium dendrobatidis is a parasitic fungus that disrupts the bodily processes of its amphibian hosts, resulting in lethargy and ultimately death. Although the exact origins of this pathogen are currently debated, Bd has been detected throughout the world and linked to dramatic amphibian population declines and extinctions (Skerratt et al . 2007).

Due to the rapidity with which Bd invades amphibian communities, swift conservation action was deemed necessary to prevent extinctions; consequently, many institutions realized the necessity of collecting wild individuals prior to the arrival of Bd with the hopes of establishing captive populations. The Amphibian Ark, for example, represents a joint effort between the ASG, the World Association of Zoos and Aquariums, and the IUCN/SSC Conservation Breeding Specialist Group. Members of these organizations worldwide participate in captive amphibian husbandry and breeding programs using wild-caught individuals (Figure 5-6). In concert with such activities, some facilities are also addressing the possibility of 'biobanking' activities, such as cryogenically preserving the sperm and eggs of imperiled species or maintaining living cell lines for future use. While some researchers are dedicated to maintaining captive populations, others are actively investigating potential treatments for Bd or preventative measures. Treatment methods are currently being investigated for amphibians already infected with Bd (Berger et al . 2010), and findings that certain bacteria confer Bd resistance have led some researchers to examine the viability of 'seeding' amphibians with protective bacterial coatings prior to reintroduction efforts (Becker and Harris 2010). Also, biologists are increasingly advocating for more rigorous chytrid monitoring protocols to prevent further spread of this pathogen, such as efforts in the United States to incorporate amphibians into the Lacey Act (1900), a federal mandate that would require them to be certified as disease-free prior to importation.

Throughout the current amphibian extinction crisis, increasing public awareness has been a critical component of conservation efforts. Amphibians typically do not receive the attention bestowed upon more charismatic megafauna, such as pandas and tigers, despite their significant economic, ecological, and aesthetic values. In a worldwide effort to bring amphibian population declines to the forefront, the Amphibian Ark declared 2008 as the "Year of the Frog," a time in which conservationists showcased amphibian diversity in zoos and aquaria while detailing their current plight. In addition, some conservation efforts, such as Project Golden Frog, utilize attractive or otherwise conspicuous amphibians as flagship species with which to garner public interest and local pride in endangered species and promote local activism (Figure 7). The ASG's 'Metamorphosis' initiative utilizes artistry to promote increase public recognition of connections between the plight of amphibians and that of humanity. Biologists have also solicited direct public involvement through citizen science programs wherein non-scientists can participate in crucial amphibian population monitoring efforts; examples of these efforts include ASG's Global Amphibian BioBlitz, Nature Canada, and Environment Canada's FrogWatch, the United States Geological Survey's North American Amphibian Monitoring Program, and the AZA's FrogWatch USA. Finally, continued research highlighting the critical ecological and economic roles amphibians play in ecosystems, such as transferring energy through food webs and reducing insect populations (Davic & Welsh 2004), has been important in cultivating popular interest in the current extinction crisis.

References and Recommended Reading

Berger, L., Speare R. et al . Treatment of chtridiomycosis requires urgent clinical trials. Diseases of Aquatic Organisms 92 , 165-174 (2010).

Collins, J. P. & Storfer, A. Global amphibian declines: sorting the hypotheses. Diversity and Distributions 9 , 89-98 (2003).

Davic, R. D. & Welsh, H. H. On the ecological roles of salamanders. Annual Review of Ecology, Evolution, and Systematics 35 , 404-434 (2004).

Ebenhard, T. Conservation breeding as a tool for saving animal species from extinction. Trends in Ecology and Evolution 10 , 438-443 (1995).

McKinney, M. L. Extinction vulnerability and selectivity: combining ecological and paleontological views. Annual Review of Ecology and Evolution 28 , 495-516 (1997).

Ralls, K. & Ballou, J. D. Genetic status and management of California condors. Condor 106 , 215-228 (2004).

Russell, W. C., Thorne, E. T. et al. The genetic basis of black-footed ferret reintroduction. Conservation Biology 8 , 163-266 (1994).

Skerratt, L. F., Berger, L. et al . Spread of chytridiomycosis has caused the rapid global decline and extinction of frogs. Ecohealth 4 , 125-134 (2007).

Stuart, S. N., Chanson, J. S. et al. Status and trends of amphibian declines and extinctions worldwide. Science 306 , 1783-1786 (2004).

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Animals in Research curriculum

Through this curriculum, students are introduced to the complex topic of Animal Research using structured discussion, stakeholder activities, case studies, and the ethicalframeworks used by those in support of, and in opposition to, this work. One of the goals of the curriculum is for students to support their own position on this issue through well-reasoned, fact-driven justifications in a classroom atmosphere of respectful dialogue.

Click here to access the full curriculum.   To view and download individual lessons, visit the Lessons page.

In order for us to measure how our curriculum resources are being used, please take a moment to  contact us  and let us know the class or classes in which you're using our lessons.  

"Students were very engaged- we had great discussions!!!" "Students are especially impacted by the various quotes. It allows them to understand so many different perspectives clearly."

Lesson One is made up of two activities. In the first activity, students begin a unit-long written conversation ( Chalk Talk ) in which they explore and share their thoughts and ideas about animal research by silently responding to statements, pictures, and questions posted on the classroom walls. The posters remain on the classroom walls throughout the unit and are revisited by students in Lessons 1, 3, and 5 of the unit. This provides teachers with a formative assessment of students’ understandings about animal research and humans’ uses of animals. In the second activity, students explore a number of human activities which result in animal deaths: raising animals for food, hunting, abandoning animals in shelters (which results in euthanasia), using animals in scientific research, driving on U.S. roads and highways. Students predict the number of animals impacted by each activity and then compare their predictions to actual numbers. In addition, students take a closer look at animals used only for scientific research and make predictions about what types and how many animals are used for this purpose. Lastly, students consider any possible benefits and supervision for each category.

Dowload Chalk Talk resources.

Dowload the Animal Uses PowerPoint Presentation that accompanies this lesson.

Students begin this lesson by watching video vignettes exploring the “3 Rs” (Replacement, Reduction, and Refinement) that guide scientists in conducting humane research with animals. Student groups are then introduced to several types of models, including model organisms, which scientists may use to answer different types of research questions. Using a set of Research Model Cards, students explore research questions and evaluate possible methods to determine the most appropriate model for answering the research questions.

Download a copy of the 3Rs Poster .

Download the Animal Model Cards .

Students are introduced to a brief history of animal research through a timeline mapping activity. Students are asked to order the events in the timeline and highlight the occurrence of significant events. A discussion about significant events and trends helps students understand the impacts of history on today’s regulations, governing bodies, and uses of animals in research. An extension to this lesson explores the meaning of the phrase Not Tested on Animals.

Download the Historical Timeline Cards .

In this lesson, students are introduced to duties-based and outcomes-based ethical theories through a series of actual quotes from people who hold different views on animal research. Students then role-play the stakeholder positions. First students identify their stakeholder’s stance as coming from a primarily duties-based or outcomes-based ethical perspective, when possible, and then students align themselves around the room based on their stakeholder’s assumed support of or opposition to the use of animals in research. While standing with other student stakeholders holding similar views, students record their group’s top three supporting arguments. Groups with different perspectives then join together for a Structured Academic Controversy to present and listen to alternative viewpoints. Lastly, students drop their stakeholder roles and further define and justify their individual position on the issue.

Download the Stakeholder Cards .

In this lesson, students read one of three case studies involving animals in research. Students work through a Decision-Making Framework in small groups, in which they identify the ethical question, determine which facts are known or unknown, consider the values of different stakeholder groups, generate possible solutions, and then make and justify a decision about the case. This is a jigsaw exercise, in which students first meet in “like” stakeholder groups to become experts on the values and concerns of that group. Teams are then rearranged so that each new group has students from different stakeholder viewpoints. After sharing the views and values of each stakeholder group with their peers, groups work together to generate options for solutions to the case study. Lastly, students come to individual decisions about the case and write a thorough justification. [Note: Some field test teachers suggest transitioning from Lesson Four directly to the Assessment   and using this lesson as a reflective tool for re-visiting the topic at a later date].

Download the Justification Framework .

  • Overview, Credits and Standards 0Credits_Overview_Standards_AR_0.pdf

At the beginning of Lesson One, students engaged in a silent Chalk Talk regarding their personal understandings and beliefs about animal research. By beginning successive lessons with students adding to these conversations, students are able to observe how these understandings and beliefs change and/or grow through the unit as they add to the “conversation.” At the culmination of the daily lessons, students engage in a whole class discussion about what they observed and how their understandings and beliefs about animal research have or have not changed over the course of the activities. This provides teachers with a formative assessment of students’ understandings about animal research and the use of animals in and by society. As a summative assessment, students will create an Action Plan of how they will exercise their personal position on the use of animals in and by society based on background information and ethical principles.

The Appendix contains a master glossary, background reading on ethical theories, information on animal research regulatory bodies, and more.

  • Cover Art FRONT_COVER_Animal_Research.pdf
  • Notebook Spine SPINE_AR.pdf


Download a free copy of a poster detailing the 3 Rs of Animal Research: Replacement, Reduction and Refinement. These principles guide scientists in the ethical conduct of animal research.


This Powerpoint presentation accompanies Lesson 1 of "The Science and Ethics of Animal Research"

This webinar was given for  National Science Teachers Association  to accompany "The Science and Ethics of Animal Research" curriculum

The AALAS Foundation has a number of helpful resources for the public.

Of special interest is the list of programs and materials that promote awareness of the benefits of biomedical research and enhance the responsible use of laboratory animals found in the Public Outreach section.

Take a guided tour through the Cedars-Sinai Medical Center's Department of Comparative Medicine with veterinarian John D. Young in this video courtesy of Americans for Medical Progress. Links referred to in this section are not supported by the Science Education Partnership Award (SEPA).

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Animal Research

Author requirements.

  • Studies involving animals must be conducted according to internationally-accepted standards.
  • Authors must obtain prior approval from their Institutional Animal Care and Use Committee (IACUC) or equivalent ethics committee(s).
  • The name of the IACUC or equivalent ethics committee, as well as relevant permit numbers, in addition to any other pertinent experimental details, must be provided at submission.
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  • Published: 25 March 2024

Automated content analysis as a tool to compare content in sexual selection research with examples of sexual selection in evolutionary biology textbooks: implications for teaching the nature of science

  • J. Kasi Jackson 1 ,
  • Linda Fuselier 2 &
  • Perri Eason 2  

Evolution: Education and Outreach volume  17 , Article number:  3 ( 2024 ) Cite this article

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 We used college-level evolution textbooks to examine the presentation of sexual selection research—a field with ongoing debates related to sex, sexuality and gender identity. Many classic sexual selection concepts have been criticized for androcentrism and other forms of gender-sex bias, specifically for de-emphasizing the female role in reproductive behaviors and over-reliance on gender-sex binaries. These classic concepts are fundamentally captured in the idea that animal reproductive-related behaviors can be grouped in sex roles (e.g. competitive males and selective females). Recently developed alternative concepts provide a more nuanced understanding of the flexibility of sexual and reproductive-related behaviors, stemming in part from growing attention to a broader range of female behavior. To assess whether students are receiving content reflecting these insights, we measured the congruence between textbook content and the scientific literature, using insects as a case study because of the importance of this group in the development of sexual selection theory, its prevalence in current sexual selection research, and the number of insect examples included in textbooks. We first coded textbook content for sexual selection concepts. We used automated content analysis to analyze a database of citations, keywords and abstracts in sexual selection research published between 1990 and 2014, inclusive of the period covered by the textbooks.

The textbooks and research literatures prioritized the same taxa (e.g., fruit flies) and sex roles as embodied in classic sexual selection theory. Both the research literature and some textbooks acknowledge androcentrism and other forms of gender-sex bias in classic sexual selection paradigms, especially competitive male and selective female sex roles. Yet, while the research literature included alternative models, textbooks neglected these alternatives, even when researchers had studied both classic and alternative views in the same insect.


 We recommend using this kind of analysis of textbook content to engage students in a conversation around the social factors that impact knowledge construction, a key part of the epistemological understanding they need for a robust grasp of the Nature of Science and of evolutionary theory.

Attempts to promote students’ understanding of the socio-scientific nature of knowledge construction, while maintaining their trust in the endeavor of science, are often framed within the context of the Nature of Science (NOS). Gender-sex and race are powerful societal, cultural, historical and biological phenomena. They are understood within complex knowledge frameworks that are challenging to capture in scientific knowledge systems. This is because those systems are often reliant on reductionist, binary-categorical, and essentialist models, which originated within racist, sexist and heteronormative frameworks (Longino 2013 ; Schiebinger 2004 ). To address this history, NOS integrates an understanding of how knowledge is shaped within simultaneously social (having to do with the interactions among scientists and within research communities) and rational (having to do with how scientists and research communities engage with their object of study) contexts. This social/rational context includes the scientific discipline and its theories and methodologies, as well as its members’ and research communities’ place within the larger society, and its attendant histories. This is manifest in the following three principles: (1) “Scientific knowledge is open to revision in light of new evidence (e.g. Scientific argumentation is a mode of logical discourse used to clarify the strength of relationships between ideas and evidence that may result in revision of an explanation);” (2) “Science is a way of knowing (e.g. Scientists’ backgrounds, theoretical commitments, and fields of endeavor influence the nature of their findings);” and (3) “Science is a human endeavor (e.g. Science knowledge has a history that includes the refinement of, and changes to, theories, ideas, and beliefs over time)” (National Research Council 2013 ). An understanding of NOS is a key ingredient in student acceptance of evolution. Specifically, students have higher acceptance of evolution when they appreciate the diversity of scientific methodologies and the nature of theory building and testing, even when controlling for interest and background in science (Lombrozo et al. 2008 ).

Understanding these NOS principles provides a foundation to challenge how science—combined with racism, sexism, heteronormativity and homophobia—maintains power differentials along presumed lines of difference. For example, eugenics—now deemed racist and sexist, among many other problems—was the mainstream and dominant research paradigm during the birth of modern evolutionary science. Scientists working within this framework were following scientific principles as they understood them, most often grounded in a positivist framework emphasizing reductionism and control. This served to maintain the status of the dominant groups, even though not all scientists at this time had this as their explicit goal (Gould 1996 ; Graves 2019 ; Subramaniam 2014 ).

Thus, teaching students about ongoing efforts to use evolutionary theory and other science either to justify or to challenge racial and other stratifications in society requires more than pointing out bias and misapplication of scientific methodologies– it must also incorporate how scientific knowledge production is intertwined with histories of racialized and gendered difference. This is especially important given the translation of scientific knowledge about human racial, sex and gender difference to the public, including biology students. For example, both interactionist and reductionist studies of hormones, sexuality and aggression have explanatory power and receive significant attention in the research community. Yet, the reductionist studies, implying that biology determines difference, have gained more coverage by the media, as well as some textbooks (Ray King et al. 2021 ). This supports an oversimplified societal narrative about hormones (biology) determining behavior that is not aligned with current scientific research (Longino 2013 ).

Although acknowledgement of the problematic history of evolutionary biology is becoming increasingly mainstream, strategies to move forward are lacking. In their absence, there has been increasing pushback and efforts to eliminate critical thinking about these issues, in large part either by banning the teaching of content that represents the current scientific consensus—especially in the area of gender-sex—or by curtailing critical frameworks that question systemic oppressions, eg critical race theory, gender studies and other critical frameworks (Rufo 2023a , 2023b ; Wallis-Wells 2021 ). The pushback against critical analyses of racism and sexism rests (1) on shifting the focus to individual identity and (2) using presumed negative impacts on these individuals, especially those from socially dominant groups, to rally support for these bans (Rufo 2023c , 2023d ; Wallis-Wells 2021 ). Thus, engaging in knowledge construction, or epistemological, frameworks that move beyond individual experience is critical.

Critical Contextual Empiricism (CCE) addresses this by framing knowledge as a communal rather than an individual pursuit (Longino 2002 ). Thus, NOS benefits from guideposts, like CCE, for navigating the social/rational processes that are included in the NOS principles, such as discourse, backgrounds, theoretical commitments, fields and histories. One CCE tenet is the argument that scientific research practices are strongest when scientific research communities are composed of more diverse groups—as long as those groups establish equitable frameworks to share and critique knowledge (Longino 2002 ). Underlying this approach is the understanding that rather than being about the identity of the individuals doing science, what is significant is their positionality, i.e. where those individuals reside in a complex matrix of identity categories and whether those with membership in these identity categories can access the power of knowledge production (Collins 2019 ). The objectivity associated with science has been privileged and historically assigned to those whose identities claim the most social, economic, and political power, leading to research outcomes supporting this division of power (Haraway 1988 ; Harding 1986 ).

CCE, coupled with the NOS principles, makes visible for students the ways in which knowledge is constructed by providing concrete examples of how scientific knowledge responds to critique. One way to capture this is to consider textbooks as a site of knowledge production, given that (1) the success of textbooks rests in their adoption by the community, and (2) they play a key role in introducing new members of the community to disciplinary norms (Bazzul 2014 ). Here we present a case study on sexual selection research on insects, which investigates how textbook content aligns with changes in research related to gender-sex, an area with changing paradigms drawn in part from larger societal and scientific discourses.

Textbooks as the Site of NOS engagement

Biology, as a research field, has begun addressing racism, sexism and heteronormativity in two ways—by attending to plasticity, variation and context when studying organisms and by acknowledging the socially constructed nature of race, gender-sex and sexuality as knowledge systems (Ah-King 2022 ; Eliot 2010 ; Fausto-Sterling 2012 ; Hyde et al. 2019 ; Lett et al. 2022 ; Montañez 2017 ; Roughgarden 2013 ; Zambrana and Williams 2022 ). Researchers have also begun to scrutinize how science textbooks address and can impact social issues related to race, gender-sex, and sexuality and gender identity (Vojíř and Rusek 2019 ).

Unfortunately, many changes in research paradigms to address racism, sexism and heteronormativity are not being transferred to the textbooks, where, outside of brief acknowledgements of past problems, textbooks often follow a strategy of avoidance (Bazzul and Sykes 2011 ; Bickford 2022 ; Donovan 2015 ). Although most include disclaimers about biology being destiny and allude to the fact that science does not provide a framework for ethical decision-making (a part of NOS), textbooks largely fail to present information to help students robustly think about race and gender-sex from a biological perspective. For example, content analyses focused on gender and sexuality found that scientific textbooks contained heteronormative assumptions (Ah-King 2013b ; Bazzul and Sykes 2011 ; Bickford 2022 ; Røthing 2017 ), gender-biased language and assumptions (Ah-King 2013b ), and gender-biased or sexist imagery (Elgar 2004 ; Good and Woodzicka 2010 ; Parker et al. 2017 ; Rosa and Gomes da Silva 2020 ; Spaulding and Fuselier 2023 ; Fuselier et al. 2018 ). In the case of race, although books are careful to challenge the idea that race is a biological construct and include evolutionary information to the contrary, they fail to challenge racism, often supported by pseudoscience, directly (Bickford 2022 ; Donovan 2015 ). For example, through a content analysis of 153 biology books (86 textbooks, 44 curricular supplements, and 23 trade books), Bickford ( 2022 ) found that although these books covered evolutionary content accurately, they did not present scientific evidence that would refute white supremacy or cis-heteronormativity. For example, Bickford ( 2022 ) found that the books often presented the lack of the validity of race as a biological construct but failed to attend to its significant role as a societal construct or to the use of science to justify racialized oppression (eg. eugenics). Overall, students lack exposure to the historical debates within biology that have led to changes in how researchers conceive of race, sex and gender as constructs in their work (reviewed in Donovan and Nehm 2020 ).

This selective or missing coverage can lead to an increase in student assumptions around biological essentialism associated with race, gender, sexuality, and gender identity. A failure to challenge social constructs of race, often grounded in pseudoscience, leads to increases in racism—even when students are then provided information intended to interrogate racialized disparities. Several studies have suggested that when biology textbooks give examples of outcomes such as diseases that are more common in one race than in others—as an attempt to address health disparities—students may develop or strengthen a belief in racial essentialism and extrapolate into other areas with racial disparities, including educational attainment (reviewed in Donovan 2015 ). To address this, Willinsky ( 2020 ) provides an overview of mixed messages about race—critiquing the falsity of race as a biological variable, while separately presenting content that uses racial groupings as a variable—in high school biology textbooks that, he argues, also reflects the how race as a concept appears in current research on race within biology. He argues that educators should integrate a historical understanding of biology’s contributions to racialized research, especially eugenics, and use the contradictory messaging present within textbooks to demonstrate the complexities of conducting research on systemic racism and racialized outcomes in health and other biological fields (Willinsky 2020 ).

Similar findings hold for beliefs about gender and sex difference. Donovan et al. ( 2019a ) investigated the impact when 8th-10th grade students read selections from biology textbooks on the students’ belief in a neurogenetic basis for sex differences in humans and interest in science. They compared a passage refuting neurogenetic sex differences with two passages endorsing neurogenetic differences—one in humans and one in plants. Students self-identifying as girls who read the endorsing passages, whether in plants or humans, were more likely to believe in sex differences grounded in neurogenetics; girls in these treatments also indicated less interest in science. A further examination of student writing after reading the passages indicated that students tended to use both sex and gender language in all treatments, with some evidence that they were distinguishing between the concepts to refute essentialism in the refutational text treatment (Stuhlsatz et al. 2020 ). Recognizing that biology textbooks also conflate biological sex differences with gendered social outcomes, the authors recommend an approach emphasizing the complex histories of science research on both sex and gender, accompanied by training for teachers on how to address this content with their students. Our study aims to provide such a resource in the case of sexual selection.

Sexual selection and changing paradigms

One area in which scientific research and other scholarly work have begun to address at least some gender-biased assumptions is sexual selection research (Ah-King 2022 ; Ah-King and Ahnesjö, 2013 ). In our previous work, we found that although some evolutionary biology textbooks acknowledge the critique of gender bias in scientific research, their presentation of sexual selection research in text, and especially in images, retains an emphasis on the work that has been critiqued for said gender-sex bias (Fuselier et al. 2016 , 2018 ). This also occurs in animal behavior textbooks, which devote more space to sexual selection (Spaulding and Fuselier 2023 ).

Although sexual selection is typically covered in evolution courses, little research has been done to ascertain how it is taught and how students understand it (Ziadie and Andrews 2018 ). Sexual selection research originated as a study of extreme differences between males and females, e.g. strong sexual size dimorphisms or other traits that occur or are highly exaggerated in only one sex, such as the classic example of the peacock’s ornamental tail. The classic view of sexual selection emphasizes stable binary sex roles with males competing, either by fighting with other males or by displaying to females who may choose the males as mates based on their displays or dominance over other males. The roles may be reversed, with female competition for mates, given changes in the environment, such as restricted nesting sites, resulting in more female animals ready to mate than have access to resources needed for mating —but this phenomena was seen to support the existence of the binary itself (Ah-King and Ahnesjö, 2013 ; Trivers 1976 ).

Feminist critiques of androcentric bias in sexual selection theory began soon after its publication (Blackwell 1875 ; Hamlin 2015 ), and work critiquing androcentric bias and offering solutions has been ongoing in the field ever since (reviewed in Jackson 2001a , b , 2014 ). After the 2000’s, the frequency of such research in mainstream animal behavior and evolution journals has increased (reviewed in Fuselier et al. 2016 ). The field has been critiqued most often for importing assumptions about human sex roles into the study of non-human organisms (e.g. Hrdy 1986 ). Additional ongoing areas of concern include acknowledging the context-specific nature of sexual behavior and mating patterns (Gowaty 2013 ; Kokko and Johnstone 2002 ), though the extent of the challenge to traditional notions of sexual selection is a subject for debate (see for example the exchange between Ah-King 2013a ; Kokko et al. 2013 ). Researchers in sexual selection have acknowledged the lack of studies of female organisms (Clutton-Brock 2009 ) and have highlighted not only sexual selection on females but also several alternative behaviors that expand the classic understanding of sexual selection, such as male mate choice, female ornaments, male parental care, female-female competition and flexible sex roles (reviewed in Fuselier et al. 2016 ).

College-level evolutionary biology textbooks present primarily classic sexual selection binary sex-role theory, although some textbooks do present some examples of alternatives to classic roles, most commonly extra-pair copulations and polyandry—situations in which female animals mate with multiple males (Fuselier et al. 2016 ). Yet, the images included in the textbooks display a more conservative representation of classically understood sex roles than the content covered in the writing (Fuselier et al. 2018 ). It is unclear how the content presented in textbooks reflects the scientific literature. One challenge to research in this area is the difficulty of synthesizing the vast amounts of information available in the literature for comparison with the textbooks, a necessity for making recommendations for how to modify content or examining how the instructor frames what the books do—or, more importantly, fail to do. Here we explore the efficacy of automated content analysis (ACA) as a tool to assess the alignment of textbook content with the scientific literature.

Automated content analysis (ACA) essentially turns text into data, using sets of algorithms to construct models that allow researchers to determine the concepts on which authors focus, as well as the relationships among those concepts. ACA has been used recently to assess and identify trends and shifts in ecology and evolutionary biology (Nunez-Mir et al 2016 ; McCallen et al. 2019 ). Essentially, ACA programs based on machine-learning (ML) identify words or word combinations that are commonly associated with one another in text by determining how frequently they co-occur in small blocks of text (3–4 lines) versus how frequently they occur elsewhere. Leximancer does not use a training set like other artificial intelligence programs might; more information about algorithms used in the program is reviewed in Smith and Humphreys ( 2006 ). Through machine learning, ACA identifies and quantifies the associations of terms to develop a thesaurus and create “concepts” and groups of concepts related to the same theme. The frequency of and relationships among concepts and themes can be calculated, assessed, and visualized. The power of this type of analysis is the large amount of literature (or text) that can be assessed in a relatively short time. ACA is thus an excellent tool for comparing the content of textbooks to the topics emphasized within the literature on a given subject. It can reveal how researchers address particular topics both currently and over time, as well as gaps or lags in textbooks’ coverage of a field.

We used insects as a proof of concept for the ML-based ACA technique because our prior research demonstrated that a wider range of sexual selection roles was presented in this taxon than in any other group used in the textbooks (Fuselier et al. 2016 ). After completing analysis of the peer-reviewed articles, we then compared all the concepts that were studied in insects to the concepts that textbooks used these insects to exemplify. We also examined whether the insects used to represent specific behaviors in textbooks reflected the insect taxa in which these behaviors were most studied in the peer-reviewed articles. We addressed the following specific research questions:

What sexual selection behaviors are studied in insect taxa in peer-reviewed literature?

Do the insect taxa described in textbook discussions of sexual selection match the insect taxa studied in peer-reviewed articles in the sexual selection literature?

How does the range of sexual selection behaviors covered in textbooks compare to the range of behaviors discussed in peer-reviewed articles?

We used four recent evolutionary biology textbooks (Table  1 ) published between 2012 and 2013 that in 2016 represented over 95% of the market share of college-level evolution textbooks in the United States. The textbooks were the same used in our prior research (Fuselier et al. 2016 , 2018 ).

We created an inventory of all insects used as examples in textbook sections devoted to sexual selection topics. The examples were classified as fitting into one of two understandings of sexual selection: classic (e.g., male-male competition, female choice) or expanded (e.g., competition among females, reproductive constraints among males, or mate choice as a mutual process).

Literature search and dataset

To construct a literature database, we used the Zoological Record collection within Web of Science (Clarivate Analytics) to identify proceedings, peer-reviewed journal articles, books and book chapters focused on sexual selection in insects. We focused on the Zoological Record because this database is the oldest database focused on animal science and is known for its focus on zoology and animal biology. It covers international journals on behavior, with an emphasis on knowledge pertinent to the study of non-human animals in the wild; it thus contains the literature most relevant to our study (Zoological Record​ on Web of Science 2024 ). Its organization by taxonomy also mirrors our study’s emphasis on taxonomic differences, and thus its structure was particularly amenable to the ways that we needed to sort the literature to answer our research questions. We limited our search to the years 1990–2014, dates for which we were able to access abstracts for the papers. This period marks a significant time frame for a renewal of interest in sexual selection, and an associated feminist critique of androcentric bias. Given that the latest publication date of our selected books was 2013, it also included the literature most likely to be covered in the books and thus ensured that the records were those most pertinent to our research questions.

We constructed our search using Boolean operators, identifying papers with topics including both ‘sexual selection’ and ‘insect’ or its variants (e.g., insects, Insecta). After reviewing the literature, we realized that this search also included research in which the insect was not the focus of the study, e.g., studies on sexual selection in flowers mediated by insect pollinators, and studies of the impacts of sexual selection on bird traits in which the traits were signaling resistance to an insect parasite. To remove these studies, we added a supertaxon search term to search separately for papers in which the supertaxon was or was not Insecta. Most studies identified by this revised search were those with the supertaxon Insecta, and all of these (n = 1581) focused on sexual selection in insects. In a smaller set of studies (n = 105), the supertaxon was not Insecta. We reviewed these manually and removed 52 publications that did not focus on sexual selection in insects. The remaining 53 papers, which did cover sexual selection in insects, were often reviews or comparative studies in which sexual selection in an insect was being compared to sexual selection in another taxon, e.g., studies comparing nuptial gifts in spiders (Arachnida) versus crickets (Insecta). These papers were included in our final dataset of 1634 papers.

We then imported the full records (including full citations, abstracts, automatic tags, and other metadata) into a database. We manually reviewed the 1634 records to sort them into our final taxonomic groupings. This resulted in nine groups, which included seven insect orders, the genus Drosophila (fruit flies), and an ‘other’ group that included all taxa that were the focus of fewer than 20 studies each. We separated Drosophila from its parent taxon Diptera (flies) because of the large number of studies on Drosophila ; there were more studies on Drosophila than on any other group (Table  2 ). We then exported these to Microsoft Excel © for automated content analysis.

  • Automated content analysis

We analyzed spreadsheets containing article titles, abstracts and manual search terms for the nine groups of insect taxa using Leximancer, a machine-learning-based program for automated content analysis (Leximancer 2019 ). To identify the most commonly studied topics in sexual selection in insects among the 1634 papers, we used an “overall” analysis of concepts in which we allowed the program to find concepts and build a thesaurus from automatically generated terms. For a second, “profiled” analysis we added “user-defined concepts” specifically related to alternatives to classic sex roles such as polyandry, mutual mate choice, alliances, etc. To verify that user-defined concepts aligned with the meaning in the text, an investigator checked the meaning in the text with the excerpts identified by the program. For example, using the compound term “female + competition” when searching for papers that addressed competition among females for mates, text excerpts that contained the two words in a sentence but did not refer to female competition were excluded (e.g., “competition experiments…showed males mated with more females”). We modified the compound concepts (e.g., “female + competition + NOT male”) and re-ran analyses until we minimized the occurrence of inaccurate matches with the text. We used measures (produced by Leximancer ® ) of the frequency and strength of association to identify what topics were most commonly studied among which taxa; we used prominence values to quantify the relationship between taxa and topic. Prominence is a combination of strength and frequency within a taxon, and prominence values > 1 indicate that the association happens more often than expected by chance.

1) What sexual selection behaviors are studied in insect taxa in peer-reviewed literature?

Overall analysis

The overall analysis identified 64 commonly occurring concepts (see Table  3 and Appendix A). The concept ‘male’ was the most commonly encountered concept in the dataset, and thus was more common than ‘female.’ Examination of the concepts most frequently co-occurring with the five top concepts revealed that research on sexual selection in insects has emphasized males over females and focused on post-copulatory selection, communication (e.g., calling), and biometrics, among other topics. All taxa had a high frequency of association with the concepts, meaning that given the taxon, we were highly likely to find papers that included the concept. But, given the concept, the strength of association with a particular taxon was low, indicating that all the commonly encountered concepts were studied in all taxa. Interestingly, the concept ‘female’ occurred most often in association with the concept ‘re-mating’ and, secondly, ‘choice.’ Re-mating was used in studies of conflict, which was one of the top associations with the term ‘sexual,’ indicating that there is a wealth of literature on sexual conflict and that it includes an examination of females re-mating, which is one of the expanded views of sexual selection because it emphasizes multiple mating by females.

Profiled analysis

In this analysis we removed very general concepts, (e.g., male, female, sexual, evolution, behavior, reproduction, and variation) that were studied in all taxa and included 16 user-defined concepts that emphasized alternatives to classic sexual selection. Removing general concepts provided the opportunity to examine more closely which insects were used to study expanded sexual selection. For example, the sheer number of studies on speciation in fruit flies impeded the program’s ability to detect associations of fruit flies with non-traditional concepts (e.g., condition-dependent mate choice).

Four of the nine taxonomic groups were strongly and frequently associated with particular expanded concepts (Table  4 ): beetles, fruit flies, butterflies/moths, and flies. Beetles and fruit flies were frequently associated with concepts related to sperm competition and conflict (sperm competition, male costs, sperm storage, conflict, polyandry, and multiple female mating). Fruit flies, beetles and crickets were associated with condition-dependent mate choice, male mate choice and female aggression. Finally, butterflies/moths were associated with female signals, mainly pheromones, and flies were associated with conflict.

Overall, expanded concepts were studied in many insect taxa, and all expanded concepts appeared prominently in two or more taxonomic groups. On average, for each concept (e.g., “female ornaments”) there were three taxa with significant prominence values. The most infrequently studied expanded concept was female reproductive success, which was only prominently associated with beetles and butterflies/moths. Beetles and fruit flies were central to the studies of expanded concepts of sexual selection. Although studies using fruit flies made up the largest proportion of papers we identified for our dataset, more expanded concepts (n = 10) were significantly prominent in beetles than in fruit flies (n = 8).

Comparison to textbooks

2) Do the insect taxa described in textbook discussions of sexual selection match the insect taxa studied in peer-reviewed articles in the sexual selection literature?

Overall, fruit flies, beetles and crickets/grasshoppers were the most commonly studied groups in the scientific literature (Table  5 ). All flies (Diptera) including fruit flies accounted for 31% of the experimental science studies. This matches well with the proportions of examples used across all textbooks combined for flies, which was also 31%. However, when we looked at individual textbooks, the proportion of examples that used fruit flies or flies ranged from 16 to 50%, with one textbook (Pearson, 33%) matching the distribution of taxa in the literature but the others with far greater or lower representation than expected based on the literature.

3) How does the range of sexual selection behaviors covered in textbooks compare to the range of behaviors discussed in peer-reviewed articles?

The profiled analysis showed that most of the alternatives to traditional sex roles were covered in two taxonomic groups—fruit flies and beetles. Therefore, if the textbooks are covering these alternatives, we would expect to see at least one of these taxa discussed in all textbooks. At least one of the two taxa did appear in all books: fruit flies appeared in all four textbooks, and beetles appeared in three of the four. However, we found that although beetles, fruit flies and flies were strongly and frequently associated with expanded examples in the literature, they were used primarily for classic examples in the textbooks. In the literature, butterflies and moths exemplified expanded sexual selection, specifically focused on female chemical signals; the books did not attend to these taxa or this topic. What did textbooks use fruit flies and beetles to exemplify? Fruit flies exemplified both classic concepts and one expanded sexual selection concept (sexual conflict) in all books. However, beetles were used only to exemplify classic sexual selection. Thus, although studies of expanded concepts in beetles are available in the literature, they are not typically used to exemplify these concepts in the textbooks.

A similar mismatch is found among the grasshoppers/crickets. Grasshoppers/crickets were often used to study expanded concepts in the literature and also occurred in all four textbooks (Tables 4 ,  5 ). However, the textbooks used them to exemplify mainly classic sex roles. Female-female interactions, signals, and aggression were prominent concepts among grasshoppers and crickets in the literature. Yet in textbooks, the expanded roles received only brief coverage—one, scent marking of males by females, was only listed in a table rather than as a detailed example in the text of the chapter. Another text used a cricket as an example of a flexible sex role, but this appeared only in the end-of-chapter questions.

The significance of our findings, in comparison to most current literature on textbooks, is that we have examined how textbooks track trends in the sexual selection research literature, responding to critiques of gendered and androcentric bias dating back to Darwin’s original writings about sexual selection (Hamlin 2015 ; Jackson 2001a ,  b ,  2014 ). Although we previously found that some textbooks acknowledge the importance of the critique of gendered and androcentric bias in their discussion of sexual selection research (Fuselier et al. 2016 ), their selected images reinforce a traditional view of classic sexual selection theory (Fuselier et al. 2018 ). In this study we find that they also do not engage with its implications when they present the content of sexual selection to their student audience.

Our work concerns the decision-making processes that affect the presentation of knowledge, using the textbooks as a case study and CCE as a framework. Key to this approach is our main finding that in general, the textbooks do not provide a thorough representation of how research in the field of evolution, specifically in sexual selection, has shifted. Our analysis of 1634 unique research papers on sexual selection in insect taxa revealed that although most studies produced work that aligned with the classic paradigm, there were many examples that expanded upon this paradigm; polyandry and other concepts related to female multiple matings were common, as was male mate choice. Additionally, relative to the textbooks, the peer-reviewed research literature reported a greater number of alternatives to classic sex roles occurring in more and different taxa.

Several insect taxa that were included in the textbooks have been used to study alternative concepts; however, instead of reflecting this diversity, the textbooks used those taxa to illustrate classic concepts of sexual selection and excluded the expanded concepts. Thus, we see more attention being paid to alternatives to classic concepts in research articles than in textbooks. One reason for this discrepancy might be due to the taxa that are used to exemplify the concepts. We found some support for this idea in that some taxa in which the alternatives were most frequently studied were not included in textbooks. But this is not the full story because even when textbook authors included taxa that were most strongly associated with alternative concepts, they still focused on the classic concepts instead of addressing the alternatives. This indicates that textbooks maintain a bias toward classic concepts over those that expand the understanding of sexual selection beyond stereotypical sex roles. For example, in the research literature on insect sexual selection, female remating is a common concept, and ‘remating’ has an association with ‘female’ that is even stronger than the association of ‘female’ with ‘choice.’ However, well-studied charismatic insects that would illustrate the benefits of mating multiply for females are not included in textbooks. One example is the honeybee ( Apis mellifera ), a species in which a queen mates with twelve males on average (Tarpy et al. 2004 ); experimental data showed that queens with more than one mate are more attractive to workers, which may give queens longer tenure and thus higher success (Richard et al. 2007 ).

This is significant in the context of research indicating that reading passages in textbooks that reinforce biological bases of difference, whether about humans or not, can lead to more student endorsement of a biological basis behind racial and gendered stratification in society (Donovan et al. 2019b ; Stuhlsatz et al. 2020 ). Thus, there is a critical need to expose students to the kinds of examples about variation in sexual behavior that we found in our review of the research literature on insects in sexual selection, whether through examples provided in the textbooks or in supplementary material to the textbook provided by the instructors. The provision of supplementary materials also offers the chance to engage directly with NOS principles, using the textbooks themselves as the place where scientific knowledge is being constructed. Our work is significant because our case study provides an example instructors can use to address this gap within the framework provided by CCE.

Recommendations for evolution education

Our recommendations align with those made by (Willinsky 2020 ). He found mixed messages both challenging and supporting genetic essentialism in a review of textbook content related to genetics and race. As a teaching strategy, he suggests that instructors directly discuss the variation in how textbooks discuss race and genetics, using this to exemplify the complexity of studying racialized biological outcomes within the historical racist context of science. We concur with his suggestion and position our work as a method to allow instructors to engage more critically with textbook content by exploring with students the social/rational process of scientific work—which necessitates a deeper dive into the formation of the research literature than is present in many textbook summations of scientific content. Our study provides strategies to strengthen the epistemological understandings that students need to ground a robust conception of NOS, by considering the communal, rather than individual, nature of knowledge construction (CCE) in the area of sex and gender difference—an area in which students, indeed all of us, are being bombarded with controversial information.

Students with a more robust understanding of the NOS, especially around the complexities of theory building and testing, understand that knowledge production involves gray areas of nuance and context (Cho et al. 2011 ). To use our work to encourage students to do this, an instructor could ask students to reflect on their views of textbooks. Rather than seeing them as all-knowing repositories that cannot be questioned, such a conversation would encourage what Bazzul ( 2014 ) describes as a reflexive process whereby students engage in ownership of the content of their fields by questioning and considering the nuances of information received. The point of this exercise is not to reinforce a simplistic understanding of the history of racism and sexism in science as a case of bias now corrected, but to have the students use the textbook as a place to think about how information is selected and shaped.

In this instance, our study would provide a strategy to consider knowledge production at the level of the community, with the community at play being the group of evolutionary biology texts, rather than any one individual book. The textbooks that we examined collectively provided coverage of insects that was more representative of the scientific literature than any individual book did. Although there was no single book whose examples of evolution in insects matched the diversity of insect taxa found in the literature, when the books were combined, their coverage came much closer to that diversity.

The use of multiple texts and resources (instead of reliance on one textbook as an authoritative source) has been used in several fields to improve students’ understanding. For example, in history, multiple texts have been used to guide college students to understand the importance of the availability of source material, which can for example be used to indicate which groups have been deemed worth preserving in the historical record and the accompanying writing of history; however, the researchers note that students require training to understand this, given that high school classes present history as a collection of facts to be memorized (Hynd 1999 ). In political science, researchers have identified a hidden curriculum within introductory textbooks that centers institutions and those who have the most power within them (mostly white men), and de-emphasizes or ignores the political contributions of those who have had to fight for equity by segregating coverage of movements for gender, sexual, and racial/ethnic equity into sections linked only to diversity and thus reinforcing the notion that those issues are outside the mainstream (Atchison 2017 ; Cassese and Bos 2013 ); the use of original source material and/or diverse sources from the field’s research literature could ameliorate this bias. Within mathematics, there has been a shift in the conception of how teachers use textbooks, with a new emphasis on teachers’ pedagogical design capacity or the ability of teachers to make decisions about how to use, adapt or add to content provided in textbooks grounded in their understanding of how to help their students learn (Matić, 2019 ). Overall, across a broad range of fields, there is growing recognition that students do not simply receive knowledge from textbooks, teachers or any other source; rather students integrate what they learn with their own frameworks, prior knowledge and goals. Projects that expose for students how textbook authors make choices in their presentation of topics thus offer a way to engage with student sense-making processes and enhance learning (Sikorski and Hammer 2017 ). Comparison across textbooks—making visible their differences as well and what they share—provides a strategy to address this.

Our finding that collectively the books did a better job than any one book in coverage of the field is key here. Instructors could share with their students how their specific class textbook covers topics in contrast to other books. This could lead to conversations about the selection of what to include and not to include and what mediates those decisions, including the authors’ positionalities—not just their identity put a multitude of associated factors based on how they move through the social world—of those doing the research or writing the books—an issue identified as critical to the construction of science by feminist scholars (reviewed in Intemann 2010 ).

Key to this conversation would be including how some of the textbooks’ authors offer overviews of the critique of androcentrism in their fields, framed by noting how those historically excluded from the research community—in the case of gender bias, normally women—corrected this bias by attending to the behavior of female animals (Fuselier et al. 2016 ). Although the discussion indicates the authors saw the value of the critique, it fails to account for the continuing emphasis on classic sexual selection theory, with its androcentric focus and gender binaries. This parallels the split presentation that other researchers found within textbooks—with mixed messaging about race, sex and gender—deconstructing bias in one place, while sharing examples that reinforce it in another passage (Bickford 2022 ; Donovan 2015 ; Willinsky 2020 ). A CCE framework opens the door for a nuanced conversation with students for the reasons behind this finding.

Bringing attention to the increased attention to female behaviors in the context of a discussion of historical and contemporary critiques of sexual selection models for androcentrism would provide a concrete example of the NOS principle that “Scientific knowledge is open to revision in light of new evidence.” This could be accomplished in part by making small shifts in the framing of some concepts and by augmenting textbook examples with examples from different taxa, such as more coleopterans, to represent a wider variety of concepts. In the research literature, Coleoptera and Drosophila were closely associated with concepts related to sperm competition and conflict (sperm competition, male costs, sperm storage, conflict, polyandry, multiple female mating), which require multiple matings among females. Reframing the presentation of sperm competition in textbooks to emphasize multiple mating by females—and the often-positive fitness consequences for females of multiple matings –would put textbooks in closer alignment with the research in this field. Having open discussions with students on the implications of centering sperm competition versus multiple mating or remating by females offers a chance to engage with the NOS principle that ‘Science is a way of knowing’ by having a discussion about the impacts of language choice on who is perceived as having or lacking agency in scientific research.

Further, some taxa used to exemplify classic sex roles, could also be used to show alternatives. A good example would be an orthopteran such as a katydid species that has flexible, condition-dependent sex roles. Although crickets, which are also orthopterans, were used in all textbooks, they were leveraged primarily to support classic sex roles. Again, a small change—adopting examples of orthopteran flexible sex roles in the main body of the chapter—would better align the books with the experimental science. In fact, research on multiple mating by females in orthopterans began in the nineties (Tregenza and Wedell 1998 ). In addition, a class discussion about the reasons why textbooks continue to center classic sex roles could engage students with the NOS principle that “Science is a human endeavor” and is thus subject to the decisions made by humans in terms of what to emphasize, de-emphasize or not to discuss.

Using ACA to track the progress of fields and how they are synthesized in textbooks

For researchers interested in extending this approach to other topics within and beyond sexual selection, we found that ACA is a promising tool for exploring how textbooks reflect the research being done in a particular field, especially which the field is undergoing change in how it approaches key concepts. Our work builds on prior attempts to assess textbook quality by comparing textbooks to the coverage of disciplinary research. For example, Bierema et al. ( 2017 ) used a combination of manual and automated content analysis to identify main topics covered in animal behavior textbooks. For automated analysis, these authors used a program that found terms in text. The difference between this and Leximancer is that Leximancer “learns” from the text and creates a thesaurus of related terms for a particular code. The investigator can then cull the inappropriate terms and ultimately “train” the program to match content with context. This is instructive because it permits researchers to see the relationships among terms and the “composition” of those terms, and then use measures of conditional probability and network analysis to quantify and visualize relationships.

The analysis by Bierema et al. ( 2017 ) determined the proportion of research articles’ abstracts that included four different central ideas in the field of animal behavior. That study used the frequency of occurrence of central ideas in this selection of journal articles, and then compared this to journal impact factor to estimate impact in the field. When they compared these results to textbooks, they found that the textbooks overall matched the literature from 28 journals in that there were similar patterns of proportions across the main topics covered. Using ACA allowed us to conduct a more detailed analysis that provided insights into the relationships among concepts. Also, our research question about taxa was specific enough that we could limit the dataset by taxa rather than by journal; this permitted a broader survey of many journals as opposed to choosing only a selection based on readership or other metrics. Instead of assessing which broad disciplinary topics are covered, we emphasize a focal area within evolutionary biology: sexual selection and the evolution of sex roles and reproductive behavior. This level of detail and nuance was significant for our topic because of our focus on a topic that arose from a critique of mainstream research. Further studies which were outside of the classic view of sexual selection appeared in taxon specific or subfield oriented journals decades before studies were published in mainstream journals (Jackson 2001a , b , 2014 ). Thus, our approach to using ACA is, therefore, appropriate when looking for emergent trends that may counter dominant narratives.

A cautionary note

There are important cautions to bear in mind for those wishing to apply the method of auto-content analysis. One of the biggest challenges is the optimization of search terms to ensure an accurate match between the concept-of-interest and the context in which it is used in the publication. For example, in this study, "multiple female matings" was used more often than “polyandry,” and thus the two terms had to be linked in the thesaurus we created. But then sentences containing the words “multiple,” “female,” and “mating” were considered to be “hits” even when the context of the sentence was not about polyandry (e.g., “…males mating with multiple females…”). Thus, validation, i.e. assessment to determine whether the program is correctly linking the concept to its appropriate context, is critical for an accurate analysis. Human knowledge is required for validation. In our case, the researchers have doctoral degrees in evolutionary biology, animal behavior and gender studies—a diverse group with deep knowledge of the scientific content, including its relation to social movements for gender equality. Additionally, we paid careful attention to the construction of the database, focusing on a collection of papers with a taxonomic focus and manually verifying that the included papers matched our criteria. The technique should be used in conjunction with other methodologies, including thematic coding of text and image analysis, as we have done in other publications (Fuselier et al. 2016 ; 2018 ).

We advocate for the textbooks in a novel way to integrate students understanding of NOS within the context of their study of content. Rather than presenting the textbook as an authoritative source of information, we suggest guiding students through a process of comparing it with the relevant research literature to understand decision making about what aspects of evolution are presented as ‘fact’ to students. This engages students with several tasks shown to be beneficial to the understanding of evolution—metacognitive vigilance (González Galli et al. 2020 ), appreciation of the Nature of Science, especially the tentative and provisional nature of science and the importance of multiple theories, understanding of epistemological beliefs–specifically that learning is changeable, not innate, and knowledge does not come from all-knowing sources– which provide the foundation for a robust understanding of both NOS and evolution (Cho et al. 2011 ).

Availability of data and materials

Data are available by request from the authors.

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Thanks to Briea St. Clair, Rayna Momen, Rachel Stoiko and Sarah Spaulding for their contributions to database construction and prior analyses.

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Jackson, J.K., Fuselier, L. & Eason, P. Automated content analysis as a tool to compare content in sexual selection research with examples of sexual selection in evolutionary biology textbooks: implications for teaching the nature of science. Evo Edu Outreach 17 , 3 (2024). https://doi.org/10.1186/s12052-024-00198-w

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Sex & Gender Analysis

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Animal Research 2: Analyzing How Sex and Gender Interact

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The Challenge

Sex is a fundamental variable that can be used to disaggregate data and explain heterogeneous disease outcomes. Although many factors can influence an outcome, sex is evolutionarily fundamental and impacts the whole of the population. Across diverse disciplines, researchers risk drawing erroneous conclusions when they extrapolate outcome data from one sex to another.

In June 2015, the National Institutes of Health released guidelines for considering sex as a variable in vertebrate animal and human (NIH, 2015; Clayton & Collins, 2014). This follows policies fostering sex/gender analysis in basic research implemented by the Canadian Institutes for Health Research (2010; Johnson et al., 2014) and the European Commission (2013). We expect the US National Science Foundation (NSF) and the European Research Council (ERC) to follow suit in the life sciences and engineering in any field with a human endpoint (Schiebinger & Klinge, 2015; Schiebinger, 2014).

Females have been underrepresented in most subfields of animal studies, except reproductive biology and immunology. Importantly, the sex of the animal is not reported in 22–42% of articles in neuroscience, physiology, and interdisciplinary biology journals” (Beery et al., 2011; McCullough et al., 2014). This is research money wasted. If sex is not reported, data cannot be included in meta-analyses.

Method: Analyzing How Sex and Gender Interact in Animal Research

How can we best design animal studies to take into account sex (biological characteristics) that interact with gender (sociocultural or environmental factors and processes)? The figure below shows the complex interdependency of sex and gender throughout the rodent life cycle.

Method: Analyzing Sex 1. Sex differences must be investigated before they can be ruled out (see Not Considering Sex Difference as a Problem ). 2. Research can be done stepwise. Male and female animals should be strain- (or strain and genotype) and age-matched, and reared under identical conditions (cages, bedding, diet). Females should not be breeders unless required for assessment of the phenotype. Step 1. Total sample size (based on power calculations): Adopting a strategy of both female and male animals or cells seems likely to allow detection of at least some sex influences, namely the largest ones that presumably researchers would first want to detect, with no impact on sample size or cost. Step 2. Sex-based powering: tests hypothesis in both males and females and power each to determine effect. Step 3. Comparison between sexes: power study to determine the actual “sex effect.” Testing for sex effects has a financial cost. However, a demonstrated sex difference justifies sex-specific research because harm in one sex is costly to society and individual patients. Overall, it is less expensive to understanding sex in the basic science phase than during the more costly clinical trial phase. This may decrease the number of drugs that fail in development and also help companies avoid being forced to remove drugs from the market due to adverse events in one sex. 3. To appreciate the presence/absence of sex effects, researchers should also evaluate overlap between groups (similarities between males and females) and difference within groups (differences among males or among females). Overemphasizing sex differences should be avoided. 4. Finding no sex effect should also be reported. To reduce publication bias, researchers should report when sex differences (main or interaction effects) are not detected or when data regarding sex differences are statistically inconclusive (Wizemann, 2012). Reporting null results is crucial for meta-analysis. For phenoytpes that do not display sex difference, future experiments should be sex inclusive, that is include equal numbers of randomly selected males and females for each test group studied. Not every experiment needs to be designed to evaluate sex differences. However, for every experiment, the sex of the animal test subjects should be noted in the article and reported in the methods section to ensure that experiments are reproducible and findings (in one sex) are not over-generalized (to the other sex) (Wizemann, 2012). View General Method  

Method: Analyzing Factors Intersecting with Sex:

  • b. In a meta-analysis of nearly 10,000 traits, Prendergast et al. (2014) found that, for most biological measurements, females are no more variable than males. Other factors, including group versus single animal housing, can have a greater impact on variability of a trait than stages of the estrous cycle.

2. Menopause Models Menopause is an emerging area of research in animal modeling studies. One study reported that immunological changes accompany this hormonal transition. Ovariectomized mice undergo "acute menopause," and exhibit "reduced lymphocyte chemotaxis, mitogen-induced T cell proliferation responses, and [Interleukin-2] production" (Marriott et al., 2006).

3. Pregnancy or Pseudopregnancy Less than 10% of medications approved by the U.S. Food and Drug Administration since 1980 has enough information to determine risks for birth defects (Adam et al., 2011; Mishra & Mohanty, 2010). New animal research that evaluates drug safety should assess effects on the dam and the fetus during pregnancy and lactation (McDonnell-Dowling & Kelly, 2015).

Method: Analyzing How Sex and Gender Interact Animal research includes the interaction between sex (biological characteristics, such as genes, hormones, age, reproductive phase, strain, etc.) and gender (socio-cultural or environmental process, such as caging practices, attitudes and behaviors of researchers, room temperature, diet, etc.). The double-ended arrows represent interactions between sex and gender Gender interacts with sex, and vice versa. Environmental processes may impact male and female animals differently, such as caging practices or differential handling. These processes may include gender . Researchers should not identify an effect as dependent on sex (or a biological trait) when, in fact, it depends on an environmental condition. View General Method  
  • 1. Caging: Individual vs. group? a. To avoid aggressive behaviors, male rodents are often caged in small groups or alone. Rodents housed alone “expend more energy maintaining body temperature, which can cause differences in parameters such as caloric intake, muscle activity, metabolic rate, fat distribution, or body size, with a plethora of potential downstream effects on bodily and cellular activity” (Ritz et al., 2014). In contrast, females are more often housed together to lower costs. Rodents housed together often sleep clustered and, as a result, expend less energy to keep warm. In this scenario a “sex difference” may be identified where, in fact, differences result from different housing conditions.
  • b. The same sized group may create different stressors for females and males. Being caged alone may itself cause stress (Ritz et al., 2014), but single housing reduces trait variability in both males and females (Prendergast et al., 2014).
  • c. Group caging can also result in self-induced or social hair loss, also called barbering (Kaleuff et al., 2006). Barbering: 1) often reflects social hierarchies in same-sex group cages (both males and females); 2) may result from the stress of overcrowding; 3) takes place in breeding groups (females barber males); and 4) occurs among lactating rodents (pups barber mothers). Barbering occurs in some strains more than others.
  • d. Cage size can limit animal behavior. For example, many cages cannot accommodate the full range of female sexual behavior. In the wild, females may dart, approach, and solicit males (Birke, 2011). For these reasons, articles should specify housing conditions, including numbers of animals per cage. Prendergast et al. (2014) found that more than half of their surveyed mouse studies failed to do so.
  • 2. Researcher/Staff Sex of researcher/staff: Experimenters may be a confounding variable in rodent research where stress is a significant factor. One study found that rats and mice demonstrated a reduced pain response in the presence of a male experimenter, as compared with an empty room, whereas the presence of a female experimenter produced no difference. Both male and female rodents showed this response, but females had a greater effect. The researchers identified this “male observer effect” as a stress response to androstenone and androstadienone, axillary secretions found in higher concentrations in males than females. In addition to stress-induced analgesia, the presence of these compounds resulted in increased plasma corticosterone levels (Sorge et al., 2014).
  • 5. Social Dynamics Edelman et al. (2013) found that rat maternal behavior mediates sex differences in play among juveniles. Simulated maternal grooming, in addition to normal maternal care, reduced play in males but not in females. This effect may be mediated by increased serotonin signaling, as maternal licking also increased serotonin receptor mRNA.

Works Cited

Adam, M., Polifka, J., & Friedman, J. (2011). Evolving Knowledge of the Teratogenicity of Medications in Human Pregnancy. American Journal of Medical Genetics , Part C., 157, 175-182.

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Long-Term Research on Avian Conservation Ecology in the Age of Global Change and Citizen Science

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Long-term bird monitoring, ecological research and conservation projects that integrate community involvement, citizen science, capacity-building, outreach, environmental education and local job creation provide some of the best examples of biodiversity monitoring and conservation programs. The goal of this research topic is to provide a global overview and exemplary case studies of long-term (10+ years) bird monitoring, ecological research and conservation projects focused on the effects of global change on tropical bird communities. Long-term and locally based biodiversity monitoring programs are essential for understanding and mitigating the effects of global change on tropical biodiversity while providing capacity-building, environmental education and public outreach. However, these programs are lacking in most tropical countries that harbor most of the world’s biodiversity. Birds are the best-known major group of organisms, comprise excellent environmental indicators, are relatively easy to monitor, and, as charismatic flagship species, are met with enthusiasm and interest by people worldwide. Bird monitoring programs using mist nets and bird banding (ringing) are especially valuable, as these safe and well-established techniques enable the use of capture-mark-recapture (CMR) models to measure population change and other demographic parameters, while making it possible to obtain blood and feather samples for genetic and isotopic analyses, examine the birds for parasites and pathogens, and study home range size, habitat use and movement ecology of the birds by tracking them with geolocators, radio or satellite transmitters. Equally important for conservation, the ability to capture and release birds makes it possible to conduct hands-on ornithological training, environmental education, awareness raising and community outreach activities with students, conservationists, villagers, decision-makers, journalists, and other local people. Bird banding, tracking and nest monitoring programs provide local jobs for research assistants, who often go on to productive careers in conservation, education, research, or ecotourism. The costs involved are relatively modest and most of the money is spent locally on salaries, room, board, and services. Long-term bird banding and ornithological research stations often provide the nuclei, infrastructure, and staff for monitoring, education, and conservation programs focused on other taxa. Bird monitoring and ecological research programs that integrate conservation, ecological research, environmental education, capacity-building, and income generation are cost-effective tools to achieve the goals of community-based biodiversity conservation and poverty reduction in the developing world. Such locally based and long-term bird monitoring programs should be encouraged, established, and supported throughout the tropics. For this special issue, we will especially solicit long-term (10+ years) research papers that: • Take place in understudied regions and work with underserved communities, • Focus on the impacts of climate change, infectious diseases and other emerging threats, • Investigate particularly susceptible avian taxa and the reasons for their declines, • Address the ecological implications of these declines, including reductions in scavenging, seed dispersal, pollination, predation, nutrient deposition and ecosystem engineering, • Study bird populations with banding, nest monitoring or geolocator/radio/satellite-tracking, and • Provide examples of best practice in integrating avian conservation and ecology research with community-based conservation, citizen science, capacity-building, and environmental education.

Keywords : Biodiversity Monitoring, Birds, Capacity-building, Climate Change, CMR, Community Science, Conservation Biology, Environmental Education, LTER, Ornithology, Tropical Biology

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  • v.29(4); 2016 Dec

Critical evaluation of challenges and future use of animals in experimentation for biomedical research

Vijay pal singh.

1 Laboratory Animal Facility, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India

Kunal Pratap

2 Pharmacogenomics, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India

Koundinya Desiraju

3 Centre of Excellence for Translational Research in Asthma and Lung Disease, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India

Devika Bahal

Ritushree kukreti.

Animal experiments that are conducted worldwide contribute to significant findings and breakthroughs in the understanding of the underlying mechanisms of various diseases, bringing up appropriate clinical interventions. However, their predictive value is often low, leading to translational failure. Problems like translational failure of animal studies and poorly designed animal experiments lead to loss of animal lives and less translatable data which affect research outcomes ethically and economically. Due to increasing complexities in animal usage with changes in public perception and stringent guidelines, it is becoming difficult to use animals for conducting studies. This review deals with challenges like poor experimental design and ethical concerns and discusses key concepts like sample size, statistics in experimental design, humane endpoints, economic assessment, species difference, housing conditions, and systematic reviews and meta-analyses that are often neglected. If practiced, these strategies can refine the procedures effectively and help translate the outcomes efficiently.


The Prevention of Cruelty to Animals Act (PCA Act-1960) 1 in India is an Act to “prevent the infliction of unnecessary pain or suffering on animals,” and it shall be the duty of the Committee for Control and Supervision of Experiments on Animals (CPCSEA) “to take all such measures as may be necessary to ensure that animals are not subjected to unnecessary pain or suffering before, during or after the performance of experiments on them.” This raises key questions: Is there a level of pain during an experiment that is “necessary”? How does one decide on how much pain is necessary or permissible? Is the pain necessary at all? Who should decide what necessary pain is? What can lead to suffering, other than pain? Can this pain be avoided with better techniques? This review discusses the importance of good experimental designs and its essential components along with systematic reviews and meta-analyses to answer these questions in relation to the use of animals in biomedical research. Animal experimentation is thought of as one of the major aspects of biomedical research and drug discovery programs, but issues relating to the sentience of laboratory animals and their ethical treatment for moral decisions need to be considered by all researchers. 2 – 4

Many researchers report issues with the reproducibility of preclinical research. 4 – 8 It has been estimated that irreproducibility of data from pre-clinical research is in the range of 51–89%, contributing to a great impact on the economic aspects of pre-clinical research worldwide. 3 , 7 , 9 Besides such major issues, ethical consideration of animal experimentation, humane procedures, and sentience of the animals are also important concerns to take care of. 10 – 13 The practice of using animal models of human diseases for drug testing is common practice among biomedical researchers and scientists. Proper experimental design is paramount to good practice and obtaining sound results, and it warrants measure to present unwanted bias, such as allocation concealment, randomization, or blinding of observers, as well as attention to such factors as eligibility criteria (exclusion and inclusion criteria), external validity, internal validity, power, and sample size. 14 , 15 A good experimental design is necessary to justify the ethical argument for carrying out the work as it eventually helps in judging the right number of animals that are needed for the experiment for ensuring reproducible results. 15 , 16 On the other hand, we neglect studies on non-pharmaceutical approaches, like exercise and meditation which may be equally effective for treating depression, but are getting little funding compared to funding for drug research for depression, as a Cochrane Depression, Anxiety and Neurosis Review Group has recently denounced. Also, NIH Director Collins stated that drugs tested on mice have 80–85% chances of failure in toxicity studies in human trials. Also, on average, only 8% of animal models are able to translate further to fruitful intervention in cancer research. 17 With such failure rates, a study also published that 47 out of 53 cancer studies cannot be replicated afterwards even though they are published in esteemed journals marked as “Significant Breakthoughs.” 18 Even under such grave situations, new animal studies are receiving funding to develop more animal models further on despite criticizing, reviewing, and troubleshooting the existing models available. To justify the use of animals in research, first justify the methods and procedures by means of literature surveys, and provide sound grounding for the chosen experimental design taking internal validity and external validity as central aspects, while also refining experiments, taking into consideration issues such as ethics, morals, and sentience. 19 According to Russell and Burch, 11 replacement alternatives refer to the procedures in which one can avoid or replace the use of animals by using inanimate systems, simulated computer programs, or invertebrates which are less susceptible to pain perception than vertebrates; reduction alternatives are the strategies which can minimize the number of animals in an experimental procedure, namely sample size calculations or harm and benefit analysis; and refinement alternatives are the procedures used to modify the surroundings or handling procedures which can enhance the welfare of animals and cause less distress and pain.

The common problems faced by researchers all over the world are experimental design, ethical concerns, animal welfare, statistical analysis, power calculation, sample size, etc. 8 , 10 These are issues that greatly affect the experimental outcomes. 5 A few of the ways forward which can help to resolve these issues are herein discussed so as to provide a better understanding of the use of animals in biomedical research.

Issues in animal research

Economic assessment.

According to an estimate from 2010, biomedical research has benefitted from global investment of up to US$240 billion, out of which basic research has been the prime beneficiary. Many of the best research ideas promising translational effects have been failing when it comes to applied research. This has created a bottleneck effect making us question the value of basic research for developing disease prevention and treatment protocols. 18 It takes almost 15 years to take approval of a drug to come to market and the cost of development is nearly $1.3 billion. 17 As Altman stated in his report in 1994, “We need less research, better research, and research done for the right reasons.” 20 Like other science fields, we also need to revise the failed protocols, troubleshoot the problems in hypotheses, and take out a predictive value by systematic review and meta-analysis as tools for creating a working model with reducing economic expenditure and animal lives. 17

Humane endpoint

A refinement procedure, as defined by Morton et al. 21 is “Those methods which avoid, alleviate or minimize the potential pain, distress or other adverse effects suffered by the animals involved, or which enhance animal well-being.” This definition endeavors the practice of humane endpoints and justify their use in experimental design effectively. Humane endpoint as defined by CCAC guidelines: “A humane endpoint can be defined as the point at which an experimental animal’s pain and/or distress can be terminated, minimized, or reduced by actions such as killing the animal humanely, terminating a painful procedure, or providing treatment to relieve pain and/or distress.” 22 If going by definition and implementation, then defining the early endpoints can be a part of good experimental design and planning. 23 Most research proposals submitted to the respective Institutional Animal Ethics Committees (IAEC) under Committee for the Purpose of Control and Supervision on Experiments on Animals (CPCSEA) guidelines in India does not include a description of humane endpoints like other countries. 24 This leads to unjustified animal suffering when animals reach severe stages and are allowed to die from experimental disease. Experiments proposed should hence include humane endpoints, decided as the level of pain or suffering to which animals should not be allowed to exceed. 25 Moreover, experimenting on a suffering or moribund animal will not generate valid experimental results. Researchers should thus emphasize the establishment of humane endpoints while designing the experiment for better outcomes and ethical study design overall. This refinement can thus not only improve the welfare of the animals but might also improve the experimental outcomes. 23

Ashall and Miller 26 have mentioned a perfect way to consider humane endpoints for the study using the endpoint matrix which divides possible humane endpoints into three main categories: scientific endpoints; justifiable endpoints; and unpredicted endpoints. Scientific endpoints are based on the actual outcome achieved after the experiment and hence termination of the study at a given point. Justifiable endpoints are based on the maximum suffering that can be caused to animals in a study as part of the study objective to be achieved after which termination is essential at that point, the so-called humane endpoint. Unpredicted endpoints are mainly based on accidental suffering, which is not covered under the aims and objectives of the study. 26 Keeping in mind such issues, European Directive 2010/63/EU provides examples of procedures with different severities by describing different endpoints applied, based on clinical signs, which include tumor progression. Humane endpoints hence help prevent unnecessary suffering in various animal experiments, improve the validity of the results leading to translational preclinical studies. 27 , 28

Species difference

Lack of understanding about “species difference” is cause of concern. Mice, rat, rabbit, and guinea pigs are commonly used laboratory animals but they are very different from each other. Despite being close to humans in terms of genetic disposition, they might express difference in terms of their pathological conditions, physiological needs, and behavioral patterns. Species differences are due to differences in the quantity and quality of DNA, RNA, and proteins at genetic and molecular levels. 29 But there is more to it than that; species difference is due to evolution, habitat, environmental conditions, geography, and behavior. Hence, researchers should be aware of all the differences between their model of choice and humans since the former can only mimic humans to a certain extent. To understand the differences between species, when developing a specific vertebrate model, it helps to understand the pathophysiology of the disease in the animal with respect to humans. Generally, selection of an animal model is based on the availability or literature available for certain models of disease and not on consideration of human pathogenesis being matched with the model animal used as they can only mimic the changes rather than typically show the exact pathogenesis. This in turn creates an aberration in final outcomes if not given consideration while interpreting the results. 30 Therefore, establishing expected outcomes by analyzing the species difference yields better understanding of the animal model of disease.

The variety of animal strains available nowadays is immense, including those that are genetically altered. Hence, researchers should be able to define their choice of animal strain to suit the particular experiment. For example, in type 2 diabetes research, most reliance is on mice models, and many studies have claimed to show promising results. There is still a high failure rate at clinical levels, which is because of mechanistic differences, such as in human biology the glucose clearance is mostly in muscles whereas clearance in mice is by liver which changes the physiology and pathology drastically. Hence, model selection with the correct species is a prime need. 29 Another study specifying that species difference can change the predictive validity of the experimental outcomes shows how species difference can make a study vulnerable to less translatability. 31 Hence, to reduce the chances one can check the predictive value beforehand by previous literature available. Other methods to reduce the chances are availability of specific strains that minimize the chances of error and increase the chance of getting relevant outcomes out of the desired animal model of disease. Strain specificity plays a critical role in predicting the working of animal models.

Housing conditions

Housing conditions not only affect the behavior of the animals but also the experimental results. Adequate temperature, humidity, and air flow have to be maintained for all the animals in the first place. 32 In animal house facilities, basic requirements are provided but specific needs of each species of animal are hardly taken care of here in India unlike in most countries. Enrichment and refinement procedures can help in reducing the stress of animals in a particular environment. 14 , 32 Enrichment procedures, aimed at providing the animals with an environment which meets their needs, provide them with opportunities to perform their species-specific repertoire and hence cause less stress in the animals which will affect their behavior in a positive way and can be considered a good option. According to the studies, enrichment when given in a mice model of cancer, leads to a significant reduction in tumor weight when compared with standard environment shows an increase in number of COX-2 positive cells leading to elevated inflammatory state of mammary gland. Also in another study fibulin-4 +/– knockout mice when given enrichment have shown less chances of arterial hemorrhage and maintained the integrity of smooth muscle cells and endothelium. 33 Hence, it can be safely assumed that animals can manifest a distorted phenotype because of being housed in captive condition as they do not live in such conditions naturally. This shows that housing conditions play an important role in such studies which otherwise would have shown negative data. This is why it is most often emphasized to maintain proper enrichment and inspection of such small yet much needed factors from time to time.

Sample size and statistics

As discussed earlier, the determination of sample size is a very important aspect of designing an experiment. Most of the studies are designed vaguely on the basis of the literature available without any effort to calculate the sample size. According to a study published by Tsilidis et al., they searched for the use of P value in animal studies on neurological diseases. They found that, out of 4445 studies conducted in the past, 1719 claimed to have “positive outputs” or “statistically significant outcomes,” which was double of what they calculated would be statistically significant. 34 This eventually leads to unethical use of animals as the sample size is either too large or too small for conducting the experiment. This in turn increases the chance of inadequate outcomes from the study. The prime factors that affect the calculation of sample size are standard deviation, type-I error, power, statistical tests, and expected mortality or attrition. 8 , 35 , 36 In such contexts, the Student’s t -test is conducted to determine the statistical significance between groups. Here we discuss the factors that determine appropriate sample size and calculation.

Factors that determine sample size

An appropriate sample size generally depends on four study design parameters: (1) minimum expected difference (also known as the effect size); (2) estimated standard deviation; (3) statistical power; and (4) significance criterion. 37

Minimum expected difference

This is the smallest measured difference between comparison groups that the investigator would like the study to detect. The smaller the minimum expected difference, the larger will be the sample size needed to detect it. This parameter can be set based on previous studies or by estimating the magnitude of difference that would be clinically or biologically important.

Estimated measurement standard deviation

This is the expected standard deviation in the measurements made within each comparison group. As the standard deviation increases, the sample size needed to detect the minimum difference increases. Ideally, the variability should be determined on the basis of preliminary data collected from a similar study population. A review of the literature can also provide estimates of this parameter, if a pilot study is not feasible.

Statistical power

This parameter describes the probability that a study would correctly reject a false null hypothesis. When the statistical power increases, sample size also increases. Ideally, one would like the power to be as close to 1 as possible but practically this is not possible since until reaching an 80% power, each animal added adds a lot to the power of the experiment, but from 80% on the curve begins to become shallow and each animal added will contribute considerably less to increase power. Hence, a power of 0.8 or 0.9 is typically considered acceptable.

Significance criterion

This parameter is the maximum P value for which a difference is to be considered statistically significant. When the significance criterion decreases (made stricter), the sample size needed to detect the minimum difference increases. Generally, the accepted cutoff for the P value is 0.05.

Calculation of sample size

The estimated sample size for comparing the means of the parameter in two groups with the Student’s t -test is calculated using the equation,

where, N is the number of samples to be taken in each group, D is the minimum expected difference between the two groups, σ is the expected standard deviation in each group, and Zc and Zp are the probabilities derived from a standard normal distribution for the cutoff P value and power value, respectively. The Zc and Zp values for common cutoff values are given in Table 1 .

Zc and Zp values for common cutoff values.

Minimizing the sample size (number of animals in this context) can be done by taking some precautions in the experimental design. They are: (1) preferring continuous measurements over categorical measurements; (2) acquiring paired data wherever possible; (3) performing one-tailed tests and (4) precise measurements which reduce standard deviation; and (5) using inbred strain of animals for the experiment. By taking care of the abovementioned points while designing the experiment and calculating the sample size, one can optimize the use of animals in the biomedical research.

Systematic review and meta-analysis of literature

Animal models are used in many experiments for understanding mechanisms and etiology of a disease, 38 or to check the safety, efficacy, outcome, and side effects of a new treatment or drug before starting clinical trials. 39 , 40 However, the results from these experiments must be accurate. 41 , 42 Reproducible and consistent results from animal models can provide reliable data of relevance to human medicine. However, if results are biased or imprecise, this might result in exposing humans to unwanted risk in clinical trials. Moreover, experimental animals are subjected to unnecessary suffering when experiments fail to provide meaningful and reliable data without any clinical relevance. 39 Therefore, there must be compelling justification for the use of animals in experiments, also from the translation point of view.

A systematic review is a literature review process focused on answering explicit research questions by identifying, retrieving, and collecting selected data and integrating the results. 38 , 42 This may be followed by a meta-analysis, the statistical method for the compilation and summarization of results and findings of large collection of independent and relevant studies. 43 The effort of combining studies systematically aims to obtain a large body of information, overcoming limitations and inconsistencies of individual studies, and thus provide more accurate information about the outcome. 43 , 44 The first meta-analysis was performed in 1904 by Karl Pearson. Gene Glass coined the term “meta-analysis” to refer to the pooling of findings statistically. Gene Glass suggests that “meta-analysis was created out of the need to extract useful information from the cryptic records of inferential data analyses in the abbreviated reports of research in journals and other printed sources.” 42

Steps in systematic review and meta-analysis

Defining or identifying the research problem is the first step in performing the analysis. Research questions are focused mainly on population / species / strain; intervention / exposure; disease of interest / health problem; and outcome measures.

The criteria should be followed just after defining the objective of the study. It is necessary to define the inclusion and exclusion criteria to avoid selection bias. Inclusion criteria should cover the following: type of study, animal characteristics, interventions, and outcomes. Duplicate articles, reviews, conference papers, commentary, and errata are excluded. Articles are also excluded based on inadequate reporting.

Different databases are searched based on the research question. It is always preferable to search more than one database. Besides electronic databases, other sources such as reference lists of retrieved articles can also be checked to identify relevant studies 45 – 47 and can also be referred for animal filters. The search terms are phrased to cover all potentially relevant articles, combined with various Boolean operators (like “AND” or “OR”).

Based on the inclusion criteria, relevant articles are retrieved by screening of title, abstract, and, where necessary, full text. Judging the work against the inclusion and exclusion criteria is performed independently by two investigators to avoid the selection bias. Dis-agreements or discrepancies are resolved by discussion or by a third investigator.

Several scales are available to improve the quality assessment of the articles. These include the Newcastle-Ottawa Scale (NOS), a method for assessing the quality of non-randomized studies (case-control studies, cohort studies, and time-interrupted series) in meta-analyses. 48 Also, CAMARADES (Collaborative Approach to Meta-Analysis and Review of Animal Data in Experimental Studies) provides supporting framework for the groups involved in the systematic review and meta-analysis of data from the experimental animal studies. 49

Relevant data are extracted from each selected article and it should be concise and focused. Description of study group, size of group, age, gender, diagnoses, treatments, follow-up, ethnicity, methods, etc., should be mentioned. Inconsistencies also need to be described. Data extraction should be performed by the number of investigators and it should be rigorous and reproducible. Discrepancy should be resolved by a third investigator. Guidelines like MOOSE (Meta-analyses of Observational Studies in Epidemiology) and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) can be used for the systematic and complete reporting of the systematic review and meta-analysis. 50 , 51

Data extracted are analyzed by using the following statistical methods: (1) Choice effect size measure; (2) Calculation of an effect size for each comparison; (3) Choice of model: random and fixed effects model; (4) Calculation of a summary effect size; (5) Calculation the heterogeneity and if so, which characteristics, and by which method; (6) Subgroup analysis: influence of factors and the effect of an intervention; and (7) Sensitivity analysis. To note if there is publication bias is an aspect of special consideration.

Description and details of all the studies, results, and quality score must be reported. Graphical display of individual study outcome and overall results should be interpreted. Statistical significance and clinical importance need to be discussed ( Figure 1 and Figure 2 ).

An external file that holds a picture, illustration, etc.
Object name is 10.1177_0394632016671728-fig1.jpg

Flow diagram of meta-analysis.

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Flowchart of inclusion and exclusion criteria.

Discussion and conclusion

In conclusion, with animal research currently being the backbone of biomedical research, its translational value must be improved as much as possible, for significant scientific breakthroughs in uncovering human diseases and improve healthcare. Using refined study designs, statistically significant sample size, ethically acceptable protocols, and proper humane endpoints in animal experimentation can decide the outcome of the proposed hypothesis and hence refine the research outcome and its reproducibility further on. Another fine strategy to refine and reduce animal number or studies is to use systematic reviews and meta-analyses to deduce the specific problems using already available literature and their chance of success or failure in a model organism. Systematic review and meta-analyses are methods designed to identify and counter the prevalence of bias and discrepancy from individual animal studies. It is essential to pre-outline the aims, objectives, and methodology for performing these techniques. The principle behind performing the analysis is that the identification and data extraction process could be performed by the independent researchers and yield replicate data. Interpretation of the primary review studies is often followed by meta-analyses. 38 Systematic reviews and meta-analyses have provided evidence that methodological error, study design, blinding out assessment, and sample size calculation in pre-clinical trials and animal model studies lead to false treatment effects. 38 , 52 Presumption that animal species predict the human outcome relies on the use of animals as surrogate models for humans. However, bias and conflict of interest make it difficult to confirm the hypothesis and evidence suggests that animal studies are inconsistent in translation to human health; 53 , 54 rather than delivering reliable answers to research questions they are often over interpreted. 55 According to Chan et al., 56 high-quality protocols of systematic review and meta-analyses can lead to transparency, rigorous study implementation, and efficiency of research and external review.

Over 5 million animal studies are available on PubMed out of over an estimated 7 million published. 57 In 2002, why systematic reviews of animal studies were not prevalent was raised in the BMJ , 58 and in the same year the requirement of systematic reviews of all relevant animal and human studies before proceeding with clinical trials was published in the Lancet . 58 , 59 In 2007, to assess the accordance between animal and human studies of treatments, a pilot study was performed to determine whether human treatments and interventions question could be answered through systematic reviews of animal trials. Discordance between the animal and human studies was found and confirmed that systematic reviews are valuable, but in spite of lack of evidence of animal research translating to human medicine, funding still goes into this area of research. 59 , 60 Geerts et al. demonstrated that it is important to perform intensive and rigorous systematic reviews of existing literature on animal research before proceeding to more research in order to look for what can be retrieved. 59 , 61 , 62 and it might be helpful to acquire knowledge by the pharmaceutical industry and academic institutions about drug failures and avoid redundant mistakes. 59 The trend of publishing animal research before effectively synthesizing existing research leads to spawning of new research as previous literature can help us understand underlying problems in translational value of so many studies. It is difficult to quantify the majority of published animal research that has not been systematically reviewed, thus posing many difficulties to clinical researchers for translating animal data. 59

Several guidelines are available that improve the reporting in articles. Procedure and study design in all the articles, but also sample size calculation, should be followed accordingly. Animal studies are often small to show the relevance of an outcome, so smaller studies are pooled to increase the power and provide more relevance to significance of outcome. 63 So, the larger the sample size, the smaller the random error is, thus providing more power to the study. Randomization and blinding should be done while designing experiments since if not done the effect size will be overestimated by 21% and 11%, respectively, in both cases. Hence, it is crucial to include both in experimental design. 64 Italian pathologist Pietro Croce argued that “results from animal experiments cannot be applied to humans because of the biological differences between animals and humans and because the results of animal experiments are too dependent on the type of animal model used.” 39 It is proven that translation of animal data to human is very challenging with sufficient fidelity. This translation is affected by numerous factors, such as biological differences between species, internal validity, differences in experimental design between animal studies and clinical trials, insufficient reporting, and publication bias. 39 , 40 Therefore, the rationalized use of animal and sample size discrepancy can be reviewed whereas disparity in translation of animal experiment to clinical trial can be resolved by pooling the inconsistencies in the results and poor sample size of different studies through meta-analysis based on specific questions. If it is considered that the effect and biases are potentially the same, then validation of the signal cannot be proven. Effect-to-bias ratio or signal-to-noise ratio in animal studies affect the predictive values and outcomes. With systematic reviews and meta-analyses, one can retrospectively choose studies with high and low ratios and get significantly closer values for current analysis. 65 It is indirect when results cannot be reproduced under similar conditions, they cannot be expected to be translatable to other species, such as humans. Therefore, it is essential to combine the studies with small and large effect size based on the specified hypothesis to check the pooled results of the independent study, in order to increase the power and the precision. Based on the result of the combined studies, feasibility and translation of animal studies in humans can be further improved.

Similarly, vibration of effect during statistical analysis is another key factor in designing and conducting an animal study. There are many variables which can sway results or expected outcomes (over a range) in a single study. So, at some level biasness is the only way out as ignoring it is not a luxury. Such variables need to be nullified to a workable extent. 65 Hence, by refining some key strategies and training students or researchers with these key concepts in laboratory animal science 66 at the time of designing or proposing a hypothesis before carrying out actual experiments on animals one can help deduce the outcome as accurately as possible and in a refined manner. Hence, researchers should focus on such critical yet often neglected points to refine experimental procedures being used in biomedical research.


The authors acknowledge the help extended by Donald Maurice Broom, Vera Baumans, Mohammad Abdulkader Akbarsha, and Anurag Agrawal by way of critical viewpoints about the literature and content. The authors thank Ravisha Rawal for editing the article.

Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding: We would like to acknowledge CSIR funded Project BSC-0403 (Visualisation of Organisms in Action [VISION]) for funding the publication of this article.

Top Myths About Animal Research

The University of Texas at Austin is dedicated to informing the public about why research with animals is essential to advancing scientific knowledge.

MYTH: Animal research is a waste of money because it cannot predict how drugs will affect humans.

FACT: There are many similarities between humans and animals.

The physiological systems of humans and other species of animals are very similar and as a result, research studies involving animals have led to critical contributions to the treatment of a wide variety of diseases. Vaccinations for polio, tuberculosis and diphtheria as well as pacemakers and cochlear implants have all been developed through research on animals. In fact, 188 of the 225 Nobel Prize award recipients in the Physiology or Medicine category used animal models in their research! (Foundation for Biomedical Research, Nobel Prizes in Medicine, 2023)

MYTH: Animal research only benefits humans.

FACT: Animal research saves human and animal lives!

Animal research not only benefits humans. It also plays a key role in the development of veterinary medicine for our pets. These discoveries include the feline leukemia vaccine and flea control methods. These advances would not have been possible without the use of laboratory animals.

MYTH: There are no laws or regulations governing the use of animals in research.

FACT: Animal research is highly regulated in the United States on the federal and local levels.

Scientists who wish to perform research with animals must receive prior approval from their Institutional Animal Care and Use Committee (IACUC). The IACUC reviews proposals while focusing on the ethical care and use of animals. The IACUC is comprised of veterinarians, scientists, non-scientists and members of the community.

Scientists and IACUCs must both comply with the United States Department of Agriculture (USDA) and the National Institutes of Health (NIH) Office of Laboratory Animal Welfare. Both federal agencies have set strict policies and regulations regarding the care and use of animals. UT Austin is also accredited by the Association for Assessment and Accreditation Laboratory Animal Care International (AAALAC), a voluntary accreditation organization that sets the gold standard for the care and use of animals.

MYTH: Most experiments are performed on monkeys, dogs and cats.

FACT: Only 1% of animal research is conducted with monkeys, dogs and cats.

99% of animal research around the world is conducted with other animals, including rodents, fruit flies, fish or other species. However dogs, cats and monkeys have and continue to contribute greatly to our understanding of the way the body works and treating diseases affecting humans and animals.

MYTH: Research animals are abused and mistreated.

FACT: The laws to protect laboratory animals in the United States are among the strictest on the planet.

The University of Texas at Austin complies with all laws and regulations set forth by the United States Department of Agriculture (USDA) and National Institute of Health’s (NIH) Office of Laboratory Animal Welfare (OLAW). UT is voluntarily accredited by AAALAC and utilizes standards set forth by the Guide for the Care and Use of Laboratory Animals.

Animal research cannot occur unless it receives prior approval from an animal welfare and ethics committee, known as an IACUC (Institutional Animal Care and Use Committee). UT employs three full-time veterinarians with specialty in laboratory animal medicine who provide around-the clock medical care. Animals are provided with clean housing, nutritious food,and environmental enrichment. A procedure that is painful in humans is assumed to be painful in animals. The use of anesthetics for potentially painful procedures plus painkillers after surgery are always provided unless the clinical study specifically disallows it. In this case, researchers must have a strong justification for why these cannot be provided.

MYTH: No scientific benefits have resulted from animal research.

FACT: Countless scientific benefits have resulted from animal research.

Without animal research, we would not have chemotherapy drugs for cancer, high blood pressure medication, the ability to perform organ transplants, insulin drugs for the diabetic, artificial joint replacements, drugs such as penicillin and other antibiotics, heart pacemakers, vaccines for polio, measles, rubella, smalli diphtheria and tetanus, and so many more medical advances.

MYTH: Animal research is no longer necessary because there are non-animal alternatives to animal experiments.

FACT: Although the scientific community has become more sophisticated with using non-animal alternatives, they cannot completely replace experiments that need to be performed in a living being.

In some cases, non-animal alternatives such as computers have been used to replace research animals. Nevertheless, while computers provide terrific resources for researchers, they do have limitations. For instance, computers are only able to provide information or models of known phenomena. Because research consistently seeks answers to unknowns, a computer is unable to simulate how a particular cell might interact or react with a medical compound, or how a complex biological system such as the circulatory system will react to a new drug directed to improve organ function.

Studies using isolated cells or tissues almost always precede animal-based research, but researchers must study whole living systems to understand the effectiveness of treatments and their potential benefits and dangers.

U.S. law requires that all new drugs, medical devices and procedures first be evaluated in animals for safety and efficacy before clinical (human) trials can begin.

MYTH: It is immoral to use animals in research.

FACT: Animal research is necessary to treat and prevent disease, and the animals are treated with the utmost respect.

The use of animals in research is a privilege that must be preserved to ensure human and animal relief from disease and suffering. Researchers seek to relieve suffering in both humans and animals by enhancing our ability to prevent, diagnose and treat disease.

A large number of major medical advances in the 20th century have occurred largely because of research with animals. Our best hope for developing preventions, treatments and cures for diseases such as Alzheimer’s, AIDS and cancer will also involve biomedical research using animals.

MYTH: Animals are an unnecessary part of the drug development process.

FACT: Animal involvement is often a necessary part of developing and testing the efficacy of drugs.

According to the Nuremburg Code, developed after World War II as a result of Nazi atrocities, any experiments on humans “should be designed and based on the results of animal experimentation.” The Nazis had outlawed animal experimentation but allowed experiments on Jews and “asocial persons.” The Declaration of Helsinki, adopted in 1964 by the 18th World Medical Assembly and revised in 1975, also states that medical research on human subjects “should be based on adequately performed laboratory and animal experimentation.”

According to the U.S. Food and Drug Administration (FDA), there are multiple steps that must be taken before a drug is determined safe and made available for humans to use. This process can take between 10-15 years.

These fish are 'living fossils'—among the most primitive animals on Earth

For 150 million years, gars—a group commonly derided as “trash fish”—have mostly stayed the same, a rare consistency not even seen in sharks, a new study says.

A fish with silver scales can be seen swimming.

If you could hop into a time machine and travel back 150 million years, the world would have looked very different. The supercontinent known as Pangaea was just beginning to break up, stegosaurs plodded across the land, and ichthyosaurs plied the seas.

But if you stuck your head into a stream, you might have spotted a familiar face.

Known as “living fossils,” gars are a group of toothy, torpedo-shaped fish that have remained relatively unchanged across vast expanses of time. Ancient gar fossils show a surprising number of similarities to the seven gar species alive today.

Of course, many species meet the criteria of “living fossil” since Charles Darwin first coined the term in 1859. (Read more:   “These 5 ‘living fossils’ still roam the Earth.” )

But now, a new study shows that, at the molecular level, gars are the most living fossil-y of all living fossils. And it’s not even close.  

A gar with baige,silver, and black scales in a brick like pattern and a flat and long mouth.

Of 481 vertebrate species, the researchers—led by Chase Brownstein and Thomas Near of Yale University and Dan MacGuigan of the University of Buffalo—found that gars have the slowest rate of molecular evolution known to science.  


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Even across millions of years, their DNA and RNA have changed up to three orders of magnitude more slowly than any other major group of vertebrates, including other classic living fossils such as coelacanths and sharks, says Solomon David , an aquatic ecologist at the University of Minnesota and co-author of the study, published recently in the journal Evolution .

The scientists believe the gars’ sluggish evolution may be due to an over-active DNA repair mechanism—a genetic quirk that could lead to advances in human medicine.

Slow evolution, “extraordinary” hybrids

To arrive at these conclusions, the authors first had to assemble an extensive family tree of species with published genomes.

Then, by zeroing in upon exons, or coding regions of DNA for all the species within that tree, they were able to estimate the rate at which a given species changed over evolutionary time.

They discovered that placental mammals, such as humans, had mutation rates of about 0.02 mutations per million years, whereas amphibians evolved much more slowly at a rate of 0.007 mutations per million years.

But gars? They averaged only 0.00009 mutations per million years at each exon site.

The study authors also report a related discovery: Gars are the most distantly diverged organisms known to hybridize—a record previously held by two species of ferns separated by some 60 million years.  

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For instance, alligator gar and longnose gar, whose territories overlap in the southern United States, last shared a common ancestor a hundred million years ago, but the species can still interbreed. What’s more, their hybridized offspring are fertile, says David. (Read more:   “Ligers, zorses, and pizzlies: How animals hybrids happen.” )

A hybrid alligator gar on a black background.

Interestingly, alligator and longnose gar hybridization isn’t some hypothetical experiment. Earlier this month, Kati Wright, a master’s student at Nicholls State University in Louisiana, hauled a six-foot, alligator-longnose hybrid out of the Trinity River in Texas,   an extremely rare find.

“When you look at their snout, it’s obvious,” says Wright, explaining the hybrid’s nose is wider than that of a longnose gar but not as wide as an alligator’s.

It may be that the gar family’s extremely slow evolutionary trajectory is what allows these distantly related cousins to continue producing offspring, since their molecular makeup is so similar, David suggests.

Carl Rothfels , an evolutionary biologist at Utah State University who discovered the hybridization between ferns and was not involved in the new study, says the level of hybridization shown in the new study is even more extreme than a human and a lemur producing fertile offspring.  

It's "extraordinary,” says Rothfels, who was not involved in the research, in an email. “Off the charts!”

Help for humans?

Aside from setting new records all over the place, the scientists believe that the gars’ evolutionary secrets, such as their efficient DNA-repair mechanism, could benefit human health­.

“As you copy DNA over and over and over again, you can get mistakes or changes,” says David. “But gars have something in there that when a mutation pops up, it gets corrected.”

David likens the process like a game of telephone that plays out over the millennia. When most organisms play it, the phrase whispered at the beginning changes over time until it takes on a totally different character by the end. But when gar play, the phrase remains nearly the same.

“If we can isolate what that is—and we’ve got some ideas as to what gene that might be—we can then take it to the next step of thinking about implications for human medicine and disease,” says David, who already breeds gar for use as model organisms.

For instance, if whatever is correcting those mutations can be replicated in human bodies, it could potentially prevent or counteract diseases such as cancer , the result of shortcomings in DNA repair and cell growth run amok.

If it all works out, there would be a delicious bit of irony for David, who spends a lot of time trying to change minds about fish that have long been persecuted for being ugly and of no commercial value.

“These fish that have been mistreated and considered ‘trash fish,’” he says, “may end up turning around and actually being extremely valuable to us from a human health perspective.”

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Research: How Different Fields Are Using GenAI to Redefine Roles

  • Maryam Alavi

Examples from customer support, management consulting, professional writing, legal analysis, and software and technology.

The interactive, conversational, analytical, and generative features of GenAI offer support for creativity, problem-solving, and processing and digestion of large bodies of information. Therefore, these features can act as cognitive resources for knowledge workers. Moreover, the capabilities of GenAI can mitigate various hindrances to effective performance that knowledge workers may encounter in their jobs, including time pressure, gaps in knowledge and skills, and negative feelings (such as boredom stemming from repetitive tasks or frustration arising from interactions with dissatisfied customers). Empirical research and field observations have already begun to reveal the value of GenAI capabilities and their potential for job crafting.

There is an expectation that implementing new and emerging Generative AI (GenAI) tools enhances the effectiveness and competitiveness of organizations. This belief is evidenced by current and planned investments in GenAI tools, especially by firms in knowledge-intensive industries such as finance, healthcare, and entertainment, among others. According to forecasts, enterprise spending on GenAI will increase by two-fold in 2024 and grow to $151.1 billion by 2027 .

  • Maryam Alavi is the Elizabeth D. & Thomas M. Holder Chair & Professor of IT Management, Scheller College of Business, Georgia Institute of Technology .

Partner Center


The Effects of Climate Change

The effects of human-caused global warming are happening now, are irreversible for people alive today, and will worsen as long as humans add greenhouse gases to the atmosphere.

case studies animal research

  • We already see effects scientists predicted, such as the loss of sea ice, melting glaciers and ice sheets, sea level rise, and more intense heat waves.
  • Scientists predict global temperature increases from human-made greenhouse gases will continue. Severe weather damage will also increase and intensify.

Earth Will Continue to Warm and the Effects Will Be Profound


Global climate change is not a future problem. Changes to Earth’s climate driven by increased human emissions of heat-trapping greenhouse gases are already having widespread effects on the environment: glaciers and ice sheets are shrinking, river and lake ice is breaking up earlier, plant and animal geographic ranges are shifting, and plants and trees are blooming sooner.

Effects that scientists had long predicted would result from global climate change are now occurring, such as sea ice loss, accelerated sea level rise, and longer, more intense heat waves.

The magnitude and rate of climate change and associated risks depend strongly on near-term mitigation and adaptation actions, and projected adverse impacts and related losses and damages escalate with every increment of global warming.

case studies animal research

Intergovernmental Panel on Climate Change

Some changes (such as droughts, wildfires, and extreme rainfall) are happening faster than scientists previously assessed. In fact, according to the Intergovernmental Panel on Climate Change (IPCC) — the United Nations body established to assess the science related to climate change — modern humans have never before seen the observed changes in our global climate, and some of these changes are irreversible over the next hundreds to thousands of years.

Scientists have high confidence that global temperatures will continue to rise for many decades, mainly due to greenhouse gases produced by human activities.

The IPCC’s Sixth Assessment report, published in 2021, found that human emissions of heat-trapping gases have already warmed the climate by nearly 2 degrees Fahrenheit (1.1 degrees Celsius) since 1850-1900. 1 The global average temperature is expected to reach or exceed 1.5 degrees C (about 3 degrees F) within the next few decades. These changes will affect all regions of Earth.

The severity of effects caused by climate change will depend on the path of future human activities. More greenhouse gas emissions will lead to more climate extremes and widespread damaging effects across our planet. However, those future effects depend on the total amount of carbon dioxide we emit. So, if we can reduce emissions, we may avoid some of the worst effects.

The scientific evidence is unequivocal: climate change is a threat to human wellbeing and the health of the planet. Any further delay in concerted global action will miss the brief, rapidly closing window to secure a liveable future.

Here are some of the expected effects of global climate change on the United States, according to the Third and Fourth National Climate Assessment Reports:

Future effects of global climate change in the United States:

sea level rise

U.S. Sea Level Likely to Rise 1 to 6.6 Feet by 2100

Global sea level has risen about 8 inches (0.2 meters) since reliable record-keeping began in 1880. By 2100, scientists project that it will rise at least another foot (0.3 meters), but possibly as high as 6.6 feet (2 meters) in a high-emissions scenario. Sea level is rising because of added water from melting land ice and the expansion of seawater as it warms. Image credit: Creative Commons Attribution-Share Alike 4.0

Sun shining brightly over misty mountains.

Climate Changes Will Continue Through This Century and Beyond

Global climate is projected to continue warming over this century and beyond. Image credit: Khagani Hasanov, Creative Commons Attribution-Share Alike 3.0

Satellite image of a hurricane.

Hurricanes Will Become Stronger and More Intense

Scientists project that hurricane-associated storm intensity and rainfall rates will increase as the climate continues to warm. Image credit: NASA

case studies animal research

More Droughts and Heat Waves

Droughts in the Southwest and heat waves (periods of abnormally hot weather lasting days to weeks) are projected to become more intense, and cold waves less intense and less frequent. Image credit: NOAA

2013 Rim Fire

Longer Wildfire Season

Warming temperatures have extended and intensified wildfire season in the West, where long-term drought in the region has heightened the risk of fires. Scientists estimate that human-caused climate change has already doubled the area of forest burned in recent decades. By around 2050, the amount of land consumed by wildfires in Western states is projected to further increase by two to six times. Even in traditionally rainy regions like the Southeast, wildfires are projected to increase by about 30%.

Changes in Precipitation Patterns

Climate change is having an uneven effect on precipitation (rain and snow) in the United States, with some locations experiencing increased precipitation and flooding, while others suffer from drought. On average, more winter and spring precipitation is projected for the northern United States, and less for the Southwest, over this century. Image credit: Marvin Nauman/FEMA

Crop field.

Frost-Free Season (and Growing Season) will Lengthen

The length of the frost-free season, and the corresponding growing season, has been increasing since the 1980s, with the largest increases occurring in the western United States. Across the United States, the growing season is projected to continue to lengthen, which will affect ecosystems and agriculture.

Heatmap showing scorching temperatures in U.S. West

Global Temperatures Will Continue to Rise

Summer of 2023 was Earth's hottest summer on record, 0.41 degrees Fahrenheit (F) (0.23 degrees Celsius (C)) warmer than any other summer in NASA’s record and 2.1 degrees F (1.2 C) warmer than the average summer between 1951 and 1980. Image credit: NASA

Satellite map of arctic sea ice.

Arctic Is Very Likely to Become Ice-Free

Sea ice cover in the Arctic Ocean is expected to continue decreasing, and the Arctic Ocean will very likely become essentially ice-free in late summer if current projections hold. This change is expected to occur before mid-century.

U.S. Regional Effects

Climate change is bringing different types of challenges to each region of the country. Some of the current and future impacts are summarized below. These findings are from the Third 3 and Fourth 4 National Climate Assessment Reports, released by the U.S. Global Change Research Program .

  • Northeast. Heat waves, heavy downpours, and sea level rise pose increasing challenges to many aspects of life in the Northeast. Infrastructure, agriculture, fisheries, and ecosystems will be increasingly compromised. Farmers can explore new crop options, but these adaptations are not cost- or risk-free. Moreover, adaptive capacity , which varies throughout the region, could be overwhelmed by a changing climate. Many states and cities are beginning to incorporate climate change into their planning.
  • Northwest. Changes in the timing of peak flows in rivers and streams are reducing water supplies and worsening competing demands for water. Sea level rise, erosion, flooding, risks to infrastructure, and increasing ocean acidity pose major threats. Increasing wildfire incidence and severity, heat waves, insect outbreaks, and tree diseases are causing widespread forest die-off.
  • Southeast. Sea level rise poses widespread and continuing threats to the region’s economy and environment. Extreme heat will affect health, energy, agriculture, and more. Decreased water availability will have economic and environmental impacts.
  • Midwest. Extreme heat, heavy downpours, and flooding will affect infrastructure, health, agriculture, forestry, transportation, air and water quality, and more. Climate change will also worsen a range of risks to the Great Lakes.
  • Southwest. Climate change has caused increased heat, drought, and insect outbreaks. In turn, these changes have made wildfires more numerous and severe. The warming climate has also caused a decline in water supplies, reduced agricultural yields, and triggered heat-related health impacts in cities. In coastal areas, flooding and erosion are additional concerns.

1. IPCC 2021, Climate Change 2021: The Physical Science Basis , the Working Group I contribution to the Sixth Assessment Report, Cambridge University Press, Cambridge, UK.

2. IPCC, 2013: Summary for Policymakers. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

3. USGCRP 2014, Third Climate Assessment .

4. USGCRP 2017, Fourth Climate Assessment .

Related Resources

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A Degree of Difference

So, the Earth's average temperature has increased about 2 degrees Fahrenheit during the 20th century. What's the big deal?

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What’s the difference between climate change and global warming?

“Global warming” refers to the long-term warming of the planet. “Climate change” encompasses global warming, but refers to the broader range of changes that are happening to our planet, including rising sea levels; shrinking mountain glaciers; accelerating ice melt in Greenland, Antarctica and the Arctic; and shifts in flower/plant blooming times.

case studies animal research

Is it too late to prevent climate change?

Humans have caused major climate changes to happen already, and we have set in motion more changes still. However, if we stopped emitting greenhouse gases today, the rise in global temperatures would begin to flatten within a few years. Temperatures would then plateau but remain well-elevated for many, many centuries.

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Explore Earth Science

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Earth Science in Action

Earth Action

Earth Science Data

The sum of Earth's plants, on land and in the ocean, changes slightly from year to year as weather patterns shift.

Facts About Earth

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AI Campaigns and Case Studies

By Joanna Fragopoulos     March 29, 2024    

case studies animal research

A rtificial intelligence (AI), and its applications, is at the forefront of many discussions in many industries and fields, from marketing to tech to healthcare to education to law. How to implement and leverage these tools in a helpful way for users can be challenging for teams. However, when used well, AI can help save time analyzing data, personalize content and information, enhance creative ideas, and find ways to promote diversity, equality, inclusion, and belonging (DEIB). Below are case studies and campaigns that successfully utilized AI.

Leveraging Chatbots and ChatGPT

Zak Stambor, senior analyst of retail and e-commerce at Insider Intelligence, discussed AI at an ANA event , stating that it is "very clear that marketers will be spending more of their budgets on AI-infused productivity tools in the future." Stambor cited two companies utilizing chatbots to help consumers find what they need. For instance, Instacart started its Ask Instacart tool to help its users "create and refine shopping lists by allowing them to ask questions like, 'What is a healthy lunch option for my kids?' Ask Instacart then provides potential options based on users' past buying habits and provides recipes and a shopping list once users have selected the option they want to try," according to the ANA event recap . Further, Mint Mobile used ChatGPT to write an ad which it later released. The recap , however, stated that the company's CMO "emphasized that there were limitations with the technology and stressed the importance of understanding a brand's DNA before using generative AI. He recommended approaching ChatGPT in the same way successful marketers approach social media."

Smoothing the Request for Proposal (RFP) Process

Creating campaigns that are actually interesting and engage people, is, of course, every marketer's dream. ZS, a consulting and technology firm focused on transforming global healthcare, worked with Stein IAS to create its campaign " Data Connects Us ," which provided client services teams with content, case studies, reports, ZS's Future of Health survey, and data to help with the RFP process. The campaign leveraged AI to create "futuristic AI generated images — such as a futuristic hospital — and coupled it with copy communicating how ZS is positioned to help connect data with people and support real innovation. By leveraging emotionally engaging, distinct, and memorable creative, ZS was able to invite consumers to learn more about the company," as described in the ANA event recap .

Fostering DEIB

Google sought to promote DEIB practices as well as combat stereotypes and bias; the company was able to do this through the use of AI in the photography space. In 2018, the company established the Google Image Equity initiative, which enlisted experts on "achieving fairness, accuracy, and authenticity in camera and imaging tools," according to the ANA event recap . This result in Real Tone, which is a "collection of improvements focused on building camera and imaging products that worked equally for people of color" and became a consideration for people potentially buying a Google Pixel. As part of this process, the company collaborated with Harvard professor, Dr. Ellis Monk; together, they released a 10-shade skin tone scale that was more inclusive of diverse skin tones. This scale helps "train and evaluate AI models for fairness, resulting in products that work better for people of all skin tones."

Unearthing Creativity

Michelob ULTRA partnered with agency CB New York to create a virtual tennis match with John McEnroe, both in the past and present. McEnroe's past self was created using motion-capture technology and AI. Moreover, the brand also created a campaign called "Dreamcaster" with Cameron Black, who has been blind since birth, who longed to be a sports broadcaster "but felt he would never get the opportunity due to his disability," as explained in the ANA event recap . The recap went on to explain that Michelob worked with Black for an entire year to "create a spatial audio portal, complete with 62 surround sound speakers and more than 1,000 unique sounds, that 'placed' him at center court and told him what was occurring during a basketball game in real time. The portal featured a vest, designed with its own haptic language, to further assist Black in following the action by allowing him to feel the game's action. After 12 months of development and training, Black became the first-ever visually impaired person to broadcast an NBA game on live TV."

Deepening Personalization

To enhance personalization, Panera Bread created a loyalty program called "My Panera" in 2010. The program gives customers rewards based on visits; the rewards to be personalized which boosts the program's engagement. Recently, Panera worked with ZS Associates to utilize machine learning to create an automated "best next action" program to enable "true one-to-one interactions with My Panera members," as described in the ANA event recap , which went on to say that the company uses a "time-based criterion, combine[s] it with several other variables identified and sorted by AI, and serve[s] more than 100 different offers to the same audience. Panera can also leverage the technology to develop multiple email subjects or coupon headlines, make product recommendations based on past purchases, and even customize colors and copy within the communication to suit the sensibilities of the customer being targeted. Overall, there are more than 4,000 unique combinations of offer and product recommendations that a customer can receive."

The views and opinions expressed in Industry Insights are solely those of the contributor and do not necessarily reflect the official position of the ANA or imply endorsement from the ANA.

Joanna Fragopoulos is a director of editorial and content development at ANA.

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  1. Animal research case studies

    Animal research case studies. UCL is a leading centre for biomedical research in the UK. Scientific research is conducted not by shadowy figures in ivory towers, but by human beings working earnestly to address major issues facing society today. Dr Clare Stanford: using mice to find treatments for ADHD.

  2. Ethical considerations regarding animal experimentation

    Introduction. Animal model-based research has been performed for a very long time. Ever since the 5 th century B.C., reports of experiments involving animals have been documented, but an increase in the frequency of their utilization has been observed since the 19 th century [].Most institutions for medical research around the world use non-human animals as experimental subjects [].

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    Research: Finding a treatment for a type of infertility in men, and understanding fundamental cell biology that could have an impact on diabetes, heart disease and immune problems. Animals used: Sea urchins, mice and hamsters 'Egg activation is really the thing that sets life going. When a sperm fuses with an egg and fertilises it, the sperm introduces a specific protein which sets off a ...

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    Read the latest Research articles from Lab Animal. ... Case Report (10) Protocol (9) Research Note (133) ... The study introduces an open-source, customizable 3D printable design for rodent ...

  5. The Emergence and Development of Animal Research Ethics: A Review with

    The Emergence of Animal Research Ethics. In his contribution to The Routledge Companion to Bioethics, Tom L. Beauchamp (2014, p. 262) calls animal research ethics "a recently coined term".It is, indeed, only in the last decade, that animal research has been discussed extensively within the framework of philosophical research ethics, but the term "animal research ethics" goes back at ...

  6. Animal Experiments in Biomedical Research: A Historical Perspective

    Moreover, animal studies on the effects of anesthetics themselves (Bernard was responsible for significant contributions to the understanding of the physiology of anesthesia: ... regardless of the purpose of research. In Regan's book The Case for Animal Rights (1983), he proposed we should extend the Kantian concept of intrinsic value to all ...

  7. Current ethical issues in animal research

    However, given our current modified utilitarian (speciesist) use of animals in non-research areas, much of the ethical debate about the use of animals in research is redundant. References. Peter Singer (2001). Animal Liberation, 1975. 3rd edition. Harper Collins. Tom Regan (2004). The Case for Animal Rights, 1983. 3rd Edition. University of ...

  8. Ethical and Scientific Considerations Regarding Animal Testing and Research

    Ethical Considerations and Advances in the Understanding of Animal Cognition. Apprehension around burgeoning medical research in the late 1800s and the first half of the 20 th century sparked concerns over the use of humans and animals in research , .Suspicions around the use of humans were deepened with the revelation of several exploitive research projects, including a series of medical ...

  9. On the past, present, and future of in vivo science

    On the past, present, and future of in vivo science. Ellen P. Neff. Lab Animal 50 , 273-276 ( 2021) Cite this article. 253 Accesses. 1 Citations. 6 Altmetric. Metrics. Lab Animal asked a group ...

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    Cats. Acromegaly in Cats. Diabetic Remission Clinic. Ragdoll cats study. A study to establish canine and feline 95% reference intervals for the QMHA Radiometer ABL800 FLEX machines. Oesophageal feeding tube placement study: using cats and dogs.

  11. A guide to open science practices for animal research

    Fig 1. Using open science practices throughout translational research studies. Application of open science practices at each step of the research process can maximize the impact of performed animal experiments. The implementation of these practices will lead to less time pressure at the end of a project.

  12. Case Studies

    CCRE, Center for Clinical and Research Ethics, Responsible Conduct of Research, PI Program, Case Studies, Ethics Educational Programming

  13. The Case for Animals in Research and Teaching

    The Institutional Animal Care and Use Committee (IACUC) reviews all research and teaching studies involving living, non-human vertebrate animals to ensure humane care and use. The Attending Veterinarian/Director of Animal Care Services oversees the care of animals, with additional oversight from the IACUC. To promote the animals' health and ...

  14. Animal research case studies

    Explore some case studies from our research involving animals at Sussex. Examples of our case studies. In this section we have included some examples of research involving animals which have been undertaken at the University of Sussex. There is one study which does not fall under the Animals (Scientific Procedures) Act (1986) (also referred to ...

  15. Saving Endangered Species: A Case Study Using Global Amphibian ...

    To date, 588 sites encompassing 920 threatened species of mammals, birds, reptiles, amphibians, conifers and corals have been identified. The goal of such efforts is to prevent the most imminent ...

  16. The current state of animal models in research: A review

    When examining the literature as a whole, however, it is clear that animal models continue to divert scarce research funding, provide limited advancement in clinical studies, and are heavily biased without proper analysis and reporting [36].In the United Kingdom (UK), while the overall number of animals used in research decreased by 7% from 2017 to 2018, the number of dogs and non-human ...

  17. Animals in Research

    Lesson Five: Case Study Decisions 5Case_Studies_AR.pdf In this lesson, students read one of three case studies involving animals in research. Students work through a Decision-Making Framework in small groups, in which they identify the ethical question, determine which facts are known or unknown, consider the values of different stakeholder groups, generate possible solutions, and then make ...

  18. Animal Research

    Studies involving animals must be conducted according to internationally-accepted standards. ... and utilized. Where research could be confused as pertaining to human clinical research, the animal model should also be noted in the article title. Non-Human Primates. ... The journal staff and editors will assess these situations on a case-by-case ...

  19. The Three Rs of Animal Research

    Title: The Three Rs of Animal Research Author: Matthew Wroblewski and Tristan McIntosh Description: Institutional Animal Care and Use Committee denies the approval of a study involving animal experimentation on the grounds that alternative methods are available. Keyword(s): Animal Subjects Research, Three Rs of Animal Research Based On:

  20. Automated content analysis as a tool to compare content in sexual

    Here we present a case study on sexual selection research on insects, which investigates how textbook content aligns with changes in research related to gender-sex, an area with changing paradigms drawn in part from larger societal and scientific discourses. ... Science studies perspectives on animal behavior research: towards a deeper ...

  21. Animal Research 2

    A National Science Foundation-funded workshop was held at Stanford University (September 2014) to conceptualize how best to: 1) include male and female animals (primarily rodents) in biomedical research, and 2) analyze sex and gender in preclinical research (Klein et al., 2015). This case study focuses on methodological innovations in rodent ...

  22. Arts-based research, animal studies and Pavlov's dogs: making the

    Introduction. Academic interest in the dynamics of human-animal relationships has been growing for some time across the social sciences and humanities, a 'nexus of interdisciplinary scholarly interest in the human-animal relationship' that is commonly referred to as the 'animal turn' (Andersson Cederholm et al. Citation 2014, 5).Increased attention to human-animal relations reflects ...

  23. Long-Term Research on Avian Conservation Ecology in the Age ...

    Long-term bird monitoring, ecological research and conservation projects that integrate community involvement, citizen science, capacity-building, outreach, environmental education and local job creation provide some of the best examples of biodiversity monitoring and conservation programs. The goal of this research topic is to provide a global overview and exemplary case studies of long-term ...

  24. Critical evaluation of challenges and future use of animals in

    Discordance between the animal and human studies was found and confirmed that systematic reviews are valuable, but in spite of lack of evidence of animal research translating to human medicine, funding still goes into this area of research. 59,60 Geerts et al. demonstrated that it is important to perform intensive and rigorous systematic ...

  25. Top Myths About Animal Research

    FACT: Animal research is highly regulated in the United States on the federal and local levels. ... anesthetics for potentially painful procedures plus painkillers after surgery are always provided unless the clinical study specifically disallows it. In this case, researchers must have a strong justification for why these cannot be provided. ...

  26. These fish are 'living fossils'—among the most primitive animals on Earth

    For 150 million years, gars—a group commonly derided as "trash fish"—have mostly stayed the same, a rare consistency not even seen in sharks, a new study says. A longnose gar swims through ...

  27. Vaccine protects cattle from bovine tuberculosis, may eliminate disease

    Bovine tuberculosis (TB) is a livestock disease that results in large economic losses to animal agriculture worldwide. The disease can also transmit to humans and cause severe illness and death. Researchers from Penn State, Addis Ababa University and the University of Cambridge have now demonstrated that a vaccine for TB currently used in humans significantly reduces infectiousness of ...

  28. Research: How Different Fields Are Using GenAI to Redefine Roles

    The interactive, conversational, analytical, and generative features of GenAI offer support for creativity, problem-solving, and processing and digestion of large bodies of information. Therefore ...

  29. The Effects of Climate Change

    Global climate change is not a future problem. Changes to Earth's climate driven by increased human emissions of heat-trapping greenhouse gases are already having widespread effects on the environment: glaciers and ice sheets are shrinking, river and lake ice is breaking up earlier, plant and animal geographic ranges are shifting, and plants and trees are blooming sooner.

  30. AI Campaigns and Case Studies

    ZS, a consulting and technology firm focused on transforming global healthcare, worked with Stein IAS to create its campaign " Data Connects Us ," which provided client services teams with content, case studies, reports, ZS's Future of Health survey, and data to help with the RFP process. The campaign leveraged AI to create "futuristic AI ...