Animal Issues/Biodiversity

Problems/Case Studies
"Who Set the Moose Loose: Trophic Interactions in the Greater Yellowstone Ecosystem". Kristina Hannam, SUNY Geneseo. State University of New York at Buffalo's National Center for Case Study Teaching
This “clicker case” focuses on the food web of the riparian bird communities of the Greater Yellowstone ecosystemand how community structure and productivity may be influenced by top-down mechanisms, resulting in a trophic cascade. As students examine the food web and non-feeding interactions among the community members, they uncover the effects of herbivore densities on songbird populations and gain an appreciation for species interactions and impacts in a biological community. The case is presented in class using PowerPoint slides (~2.6MB) that are punctuated by multiple-choice questions which students answer using clickers, though the case could be adapted for use without these technologies.
Designed for an introductory biology course taken primarily by freshmen and sophomores to fulfill a general education requirement, it could also be used in an introductory course for biology majors.

"Threats to Biodiversity: A Case Study of Hawaiian Birds", Sarah K. Huber, University of Massachusetts at Amherst, and Paula P. Lemons, Duke University. State University of New York at Buffalo’s National Center for Case Study Teaching
This case study analyzes the impact of introduced species on the bird populations of Hawaii. Students learn about what makes a certain introduced species more likely than another to become established in a new area; how introduced species can directly and indirectly affect endemic species; and why certain endemic species are particularly vulnerable to introduced species.
Developed for an introductory biology course, the case could also be used in in upper level courses such as ecology, conservation biology, evolution, diversity, and the biology of social issues, or in a non-majors biology course.

"Search for the Missing Sea Otters: An Ecological Detective Story". Mary E. Allen and Mark L. Kuhlmann, Hartwick College. State University of New York at Buffalo’s National Center for Case Study Teaching
Using a progressive disclosure format, this case study teaches students how to apply ecological principles to a real-life ecological problem--the decline in sea otter populations in Alaska. Students interpret data from graphs and tables and practice developing testable hypotheses as they work in groups to solve the mystery of the "missing" sea otters.
This case is appropriate for high school general biology and environmental science classes, and undergraduate ecology, zoology, and marine science/oceanography courses.

"The Effects of Coyote Removal in Texas: A Case Study in Conservation Biology". Margaret Carroll, Framingham State College. State University of New York at Buffalo’s National Center for Case Study Teaching
This interrupted case study presents published data on the effect of coyote removal in Texas. It was designed to help students in introductory level biology courses understand trophic level relationships and the role of keystone species. Students interpret data presented graphically and predict how changes at one trophic level may affect populations and communities at other trophic levels.
This case is appropriate for high school and undergraduate ecology, environmental science, and wildlife management courses.

"Too Many Deer! A Case Study in Managing Urban Deer Herds". Eric Ribbens, Western Illinois University. State University of New York at Buffalo’s National Center for Case Study Teaching
A town meeting is the setting for this role-playing case study in which students explore the topics of overpopulation, bioethics, and management of urban wildlife.
Although developed for a non-majors biology course, by restructuring some of the activities and asking different questions the case could be successfully used in an introductory biology course for majors, an ecology course, a conservation biology seminar, or a course on bioethics.

"The Galapagos". Nancy A. Schiller and Clyde F. Herreid, University at Buffalo. State University of New York at Buffalo’s National Center for Case Study Teaching
Using problem-based learning and role-playing, students analyze the geological origins of the Galapagos Islands, their colonization, species formation, and threats to their biodiversity in this story of a graduate student caught between local fishermen and government officials fighting for control of the islands’ natural resources.
The case was designed for an introductory biology course where the focus is on evolution. It would also be appropriate for courses in ecology, conservation biology, and natural resources management.

"The Bear Facts: Grizzly Recovery in the Bitterroot Ecosystem". Grace A. Wang, Pennsylvania State University. State University of New York at Buffalo’s National Center for Case Study Teaching
In this decision case, students consider the pros and cons of reintroducing grizzly bears into the northwestern United States as they learn about natural resource policy and the wildlife management decision-making process.
This case is appropriate for undergraduate natural resource management, wildlife management, ecology, and environmental science courses.

"The Wolf, the Moose, and the Fir Tree: Who Controls Whom on Isle Royale?". A Case Study of Trophic Interactions. Gary Fortier, Delaware Valley College. State University of New York at Buffalo’s National Center for Case Study Teaching
In this analysis case, students study predator-prey dynamics in the Isle Royale National Park ecosystem, drawing on data and findings reported in the scientific literature.
The case was developed for a sophomore ecology class. It could also be used in environmental science courses.

"Dialogues as Case Studies : Endangered Species Act". Student papers by Andrew Abramowitz and Helena Bokobza. State University of New York at Buffalo’s National Center for Case Study Teaching
Students explore the issues surrounding the controversial Endangered Species Act in a series of "dialogue" papers over the issue of whether Atlantic Salmon in rivers in the State of Maine should be protected.

"Disappearing Marine Iguanas: A Case of Population Collapse". Conrad Toepfer, Brescia University. The National Center for Case Studies Teaching in Science.
In this interrupted case study students apply the scientific method to probe possible reasons behind declining marine iguana populations in the Galápagos Islands.  Initially students are given rudimentary information and encouraged to generate wide-ranging hypotheses.  Students are then given further information to help them refine their initial hypotheses into single, testable statements.  As the case progresses, students shift to an examination of experimental methods and data interpretationOver the course of the case, they utilize both inductive and deductive reasoning in developing their conclusions about the factors influencing marine iguana populations.

"On the Road to Extinction?".  RS Donham, DE Allen.  Thinking Toward Solutions:  Problem-Based Learning Activities for General Biology.  Allen, D. E. and Duch, B. J. (1998).   New YorkSaunders College Publishing, pp. 134-139.  

      Stage 1:  "The beleaguered scientific expert" -Students investigate population bottleneck and the cheetah and the significance of variation in animal        species. 

      Stage 2:  "Another not-so-satisfying meeting" -Scientists in the scenario are obstinate about accepting the homozygosity of the cheetah and affirm that they may be on a one-way road to extinction, being a natural process.  Students investigate the processes argued in the study and how the scientists’ views could be changed.  Students will also reason whether the cheetah should be moved to a new area and where. 

"Camping with Caterpillars".  HB White.  Thinking Toward Solutions:  Problem-Based Learning Activities for General Biology.  Allen, D. E. and Duch, B. J. (1998).   New YorkSaunders College Publishing, p 129-133.     
        Stage 1:  "The Gypsy Caterpillar Invasion"- Gypsy moth caterpillars are everywhere.  Gypsy moths are introduced exotic species that have multiplied in number.  Students discuss the life cycles of moths and caterpillars, population explosion, and plant defense against the caterpillars.
        Stage 2:  "The lights go on for Bob"- Caterpillar hunter beetles and cuckoos feast on moths and caterpillars, respectively.  The character thinks of a system of checks and balances (introducing more species ) to counteract the moth population explosion.  Students reflect on factors that influence gypsy moth survival from the perspective of the moth.        
        Stage 3:  :"A mystery killer"-
Awaking one damp morning to find all of the caterpillars in the trees dead but the ones in glass jars alive, students investigate what may have caused the caterpillars to die and how this event could be integrated into a camp summer program. 

"Where Have all the Froggies Gone?".  DE Allen.  Thinking Toward Solutions:  Problem-Based Learning Activities for General Biology.  Allen, D. E. and Duch, B. J. (1998).   New YorkSaunders College Publishing, p 125-128.
        Stage 1:  The study involves an NSF conference on the disappearance of frogs and salamanders.  Students follow a public health expert who develops a task force to combat the disappearance.  Students evaluate man’s impact on the environment and the relationship with frog population decline.

"Why do we love vultures?".  SC Wildlife Federation Newsletter "Kid's Page".  December/January 2006/2007. 
This case study looks at the rapid decrease in vulture populations in the past ten years.  The reason for their plummeting numbers is the drug diclofenac.  In India and Pakistan, this medicine has been given to cows.  It is used by veterinarians to help animals feel better.  After the vulture eats the cow carcase, the medicine causes the vulture's kidneys to stop functioning.  The drug has been banned in India.  Captive breeding centers are trying to rebuild the vulture population.  This is an informative essay but could easily be used as a lead-in for research.  A research packet is available with the original research articles for the essay. 

"Tree Thinking".  Biological Inquiry:  A workbook of investigative cases.  Waterman, Margaret, and Stanley, Ethel.  Campbell-Reese. pp.  43-58.
The issue in this case study deals with the conservation of whales and whale meat.  Biotechnology is introduced as PCR methods trace endangered meat being sold in the black market.  Systemantics, classifying diversity, cladograms, and primitive versus derived characteristics are investigated.  Students also write a position paper on whaling.

"Galloper's Gut".  Biological Inquiry:  A workbook of investigative cases.  Waterman, Margaret, and Stanley, Ethel.  Campbell-Reese. pp.  91-104. 
Students learn about the specialized diets that competition horses are fed along with the pasteurland requirements.  The physiology of the horse digestive system is discussed along with helpful microbes that aid in cellulose digestion.  Reproduction in mammals is also investigated.  The evolution of the horse diet and foot structure is introduced.

"Back to the Bay".  Biological Inquiry:  A workbook of investigative cases.  Waterman, Margaret, and Stanley, Ethel.  Campbell-Reese. pp.  105-122.
The nuisance of having a large gull population around a marina sets the stage for this case study.  One marina employs gull distress calls to keep other gulls away.  However, these distress calls are hindering the relaxation of the human marina consumers.  Students answer questions about behavioral ecology.  Students design an experiment to determine if the response to distress calls is learned in the herring gulls.  Sonograms are viewed and compared. Population growth and control is of primary interest to the students.

CNN Video Clips

Topic:  "Endangered Sea Turtles": Environmental Science 5th Ed. CNN Ed (1:45 min)
Recently in Florida, hundreds of Loggerhead turtles were found exhibiting severe illnesses.  Experts at the Hidden Harbor Turtle Hospital in Marathon Key, Florida, have been nursing the sick turtles back to health, but no one is sure of the cause of the illness.  Some suspect it may be a virus, bacteria, or toxic algae in the water.  However, other species of turtles in the same waters remain unaffected by the illness.  Another theory is that the eating habits of the Loggerhead turtles may play a part in their illness.  The Loggerheads are carnivores with a diet consisting primarily of shell fish, snails, and crab.  Other turtles such as the Green turtle remain unaffected by the illness, possibly because they are herbivores eating only plants.  The worksheet includes the URL to The Turtle Hospital web site.  (Student worksheet provided on CD)

Topic:  "Whaling": Environmental Science 7th Ed. CNN Ed (1:28)

According to the Journal of Science, research of whale DNA indicates a large variation in the genetic code, which typically occurs in large populations. Over the past century, commercial whaling and hunting has devastated much of the whale population. In fact, at one time, nearly 240,000 Humpback whale species swam in the Atlantic Ocean, but excessive commercial hunting has left the ocean with about 10,000 whales remaining. Scientists estimate that the ocean once contained at least 360,000 Fin whales, while only 50,000 remain today. Many researchers and environmentalists are concerned it may take decades to restore the whale populations, but they warn that without government regulation of commercial whaling, regulation may be too late to save the remaining species. The worksheet contains the URL for the International Whaling Commission website.  (Student worksheet provided on CD)

Topic:  "Biodiversity": Environmental Science 6th Ed. CNN Ed (2:29 min)
The forest, oceans, coral reefs, marine life, algae, insects, and other living organisms make up a web of life known as biodiversity.  Currently, over two million species of plants and animals have been discovered, and scientists believe that there may be 50 times as many that remain to be discovered.  However, some scientists believe that the expanding human population, logging, mining, and fossil fueled industries may change the balance of biodiversity and drive species to extinction.  At the first Earth Summit in Rio de Janeiro ten years ago, world leaders signed a treaty to prevent the crisis; however, the treaty set general guidelines, and without the support of world nations, it was not effective in enforcing the laws.  The worksheet contains the URL for the Time Magazine website.  (Student worksheet provided on CD)

Topic:  "Biomagnification": Environmental Science 6th Ed. CNN Ed (2:11 min)
As we release pollutants into our environment, trace chemicals are sometimes absorbed by small organisms.  As small organisms are consumed by larger organisms, the toxins can pass on and become more concentrated in the larger organisms.  As the chemicals move higher up the food chain, the chemicals magnify in intensity, a process known as biomagnification.  According to researchers, eating certain seafood may lead to an increased exposure to mercury.  Exposure to mercury can result in an increased risk of the following:  blurred vision, deafness, coma, heart attack, or even death.  Those primarily at risk are small children, nursing mothers, pregnant women, and grown men.  Some of the least risky seafood include most shellfish, salmon, halibut, catfish, and other small oceanic fish.  Fish that may be contaminated with mercury include fresh or frozen tuna, marlin, or red snapper.  Researchers recommend avoiding seafood, such as swordfish, shark, tilefish, and king mackerel.  The Food and Drug Administration recommends individuals consume 2–4 servings a week from a variety of fish species, which contribute to the cardiovascular benefits of omega-3 fatty acids.  The worksheet includes the URL to the Monterey Bay Aquarium website.  (Student worksheet provided on CD)

Topic:  "Global Extinction": Environmental Science 7th Ed. CNN Ed (1:42)

According to the Journal of Nature, scientific evidence indicates that it is likely that global warming is increasing faster than originally thought. Researchers predict Earth’s global temperature could rise by a few degrees over the next 50 years, causing climate changes throughout the globe. As a result of the climate changes, Earth may experience changing weather patterns, further melting of polar ice caps, increasing sea levels, and flooding along coastlines. In addition, climate changes may cause a global extinction of nearly 1 million species, which equates to between 18 and 35% of the plant and animal species on Earth. Researchers conclude that the U.S. and other countries need to develop cleaner burning fuels and reduce greenhouse gas emissions to combat the rise in global temperatures.  (Student worksheet provided on CD)

Topic:  "Saving Guanacos": Biology 6th Ed. CNN Ed 2002 (2:53)
Guanacos are the wild cousins of the domestic llamas. It is estimated that only a few hundred thousand survive. They have been hunted for their coats and by sheep farmers who consider them pests. In fact, studies have shown that guanacos do not spread diseases to sheep or decrease the amount of forage available to them. One way to save this species may be to convince farmers that it has economic value as a source of highly valued wool. (Student worksheet provided on CD)

Topic:  "Stressed Salamanders": Biology 7th Ed. CNN Ed 2003 (3:23)
Something is affecting the salamanders that live near Cornell University's golf course.  Other populations as well as specimens gathered from the area before the golf course existed have spots that line up on either side of the body.  The population near Cornell’s golf course has asymmetrical spots.  One theory is that the salamanders are being affected by runoff of chemicals from the golf course.  The manager of another golf course defends the course and says that it promotes the health of wildlife.  He suggests that other factors, such as drought, may be causing the change in spotting. (Student worksheet provided on CD)

Topic:  "Gorilla Poaching": Biology 8th Ed. CNN Ed 2004 (1:59)
An outbreak of poaching has caused the deaths of six mountain gorillas. Primatologist Amy Vedder, who studies this species, notes that only about 660 mountain gorillas remain in the wild. They are confined to a limited range that encompasses part of three African nations. The animals are not consumed as food, but poachers seem to be attempting to capture a baby gorilla for illegal sale to a private individual. The worksheet includes the URL for the World Wildlife Fund’s gorilla information page. (Student worksheet provided on CD)

Topic:  "Lizard diversity".  Biology 8th Ed. CNN Ed 2004 (1:33)
Scientists at the University of Washington in Saint Louis examined the characteristics of lizard families and found that families varied in their degree of morphological variation. For example, one family of lizards includes members that have a variety of different body shapes and diets, although they all share a similar habitat in the deserts of Australia. In contrast, a group of South American lizards lives in a greater variety of habitats, but its members have a more consistent body shape and diet. Researchers suspect that the variation in morphological diversity among species within a family indicate that some families may tend to evolve more quickly than others.

Topic:  "Goodbye guinea worm":  Biology 5th Ed. CNN Ed 2001 (2:59)

Citizens of Ghana are shown suffering from guinea worm infection.  They became infected when they drank water containing the larval form of the worm.  Over the course of a year, the larvae develop into adults that can reach up to three feet in length.  Emergence of adult worms through the skin causes pain, scarring, and secondary infections.  Ex-President Jimmy Carter is working to eradicate the Guinea worm by teaching people to treat potentially infective water with chemicals and filtration and to monitor and treat known infections.  These efforts have succeeded in decreasing the number of infections in Ghana by ninety-five percent.

Topic:  "Seahorse Pregnancy":  Biology 7th Ed. CNN Ed 2003 (2:36)
In seahorses, offspring develop inside the male's body.  Seahorses are monogamous, and some species mate for life.  Daily courtship rituals reinforce the pair bond.  During mating, the female deposits eggs into the male's abdomen.  The eggs contain all the nutrition required to fuel development.  Once the young are born, there is no additional parental care.

Topic:  "Dolphin Sixth Sense":  Biology 2004 (1:04)
Researchers are studying the ability of dolphins to use echolocation. The animals emit sound waves and derive information about their environment by analyzing the sound that bounces back. Captive dolphins can be trained to use echolocation to identify objects hidden behind a screen. Using this method, scientists demonstrated that dolphins can discriminate between two otherwise identical cylinders that differ by a millimeter in their wall thickness. The study is described in the 7 August 2003 issue of Nature.

Topic:  "Fish on Prozac":  Biology 2004 (1:57) 
Drugs ingested by humans are excreted into the toilet and carried to sewer systems. Most sewage treatment plants remove debris and microorganisms but do not test for or remove drugs and other man-made chemicals. As a result, these chemicals are being released into our lakes and streams. Bryan Brooks, a toxicologist at Baylor University, examined fish living in waters downstream from a sewage treatment plant. He found traces of medications and personal care products in their tissues. It is possible that this chemical contamination may alter fish behavior or their ability to reproduce. It may also affect the invertebrates on which the fish feed.

"On the Termination of Species" Gibbs, W.W.  Current Issues in Biology. Scientific American, Inc. November 2001. 30-41.
This article focuses on extinction rates and how the world might be on the verge of a mass extinction. Scientists are trying to figure out how fast species are disappearing and the articles explains several models that are being used. It explains how the difficulties in determining the extinction rate. One of the suggestions in the article is to buy large tracts of land where natural selection can take place in the absence of human interference. This article is followed by a short quiz and critical thinking questions.

"The Ecology Action Guide:  Action for a sustainable future". Hickman, G. C. & Hickman, S. M. (2002).  Boston:  Pearson Education, Inc.
This simple guide offers and overview of the subject of ecology for students interested in the field.  Interviews with students, vocations, and short chapters covering overcrowding, pollution, biodiversity, and biomes will introduce students to ecology.  Checklists to reduce one’s ecological footprint and ways to get involved make up a fair portion of the book. 

“Should We Care About a Worm’s Social Life?  Pines, Maya.  The Genes We Share with Yeast, Flies, Worms, and Mice:  New Clues to Human Health and Disease.  Howard Hughes Medical Institute (2001). 
Caenorhabditis elegans worms do not eat alone.  Other groups do prefer eating alone.  This is important as specific mutations in the worms may give insight to human disorders.  Sociable worms were hyperactive, a measurable trait that can be useful in determining whether the worms were antisocial due to situational context or intrinsically antisocial during feeding. Also, the article mentions the development of sexual organs in C. elegans and the link to cancer in humans. 

"Endangered Wild Equids".  Moehlman, Patricia.  Scientific American.  pp. 33-41.
Only seven species of wild equids remain- 3 asses, 3 zebra, and 1 wild horse.  Most of these are now listed as endangered by the IUCN.  In grasslands, the equids form stable groups where all females feed together.  A male keeps his "harem".  In contrast, dry environments cause the only long-term grouping to be a mother and her foal.  The main causes for endangerment are overhunting and habitat destruction.  The article investigates the likelihood of one system of social organization to benefit the species to prevent extinction. 

Ecology Resource Page

This website offers multiple ecology-related resources. 

"Resources for Teaching Biodiversity Conservation" Network of Conservation Educators and Practicioners.
Website provides teaching resources in Conservation Biology and Biodiversity.

New Zealand Ecological Society Page
This website offers information on the ecology of New Zealand.

Land And People. Volume 19, Number 1. (Spring/Summer 2008) - Available in PBL Resource Cabinet in SCIC outside of room 207
Provides short articles and information with regard to land conservation and the human impact.

Land And People. Volume 20, Number 1. (Spring/Summer 2008) - Available in PBL Resource Cabinet in SCIC outside of room 207
Provides short articles and information with regard to land conservation and the human impact.

Articles in "Taking Sides"

"Is Biodiversity Overprotected?" Easton, Thomas. Taking Sides: Environmental Issues, Eleventh Edition.
Issue Summary:
"Is Biodiversity Overprotected?".  Easton, TA.  Taking Sides:  Clashing views on environmental issues, twelfth edition.  2007 McGraw-Hill, p.54-69.
Issue Summary:
           YES:  "Regulating biodiversity:  Tragedy in the political commons".  David Lebland             NO:  "Silenced spring:  disappearing birds" . Howard Youth.