To advance student understanding of why diversity within and among species is important.
Biodiversity is a term we use to describe the variety of all living organisms—from animals to plants to fungi to microorganisms—that live in a particular habitat. While biodiversity can be measured by the number of species present in an ecosystem, the genetic diversity within those species and the diversity of different ecosystems across larger regions also is important. Equally important is the diversity of subdivisions of species, such as subspecies and populations, because it is this diversity that leads to the evolution of new species in the future.
As the Benchmarks for Science Literacy states, students do not generally have difficulty grasping the notion that species depend on one another and on the environment for survival. But their awareness must be supported by knowledge of the kinds of relationships that exist among organisms, the kinds of physical conditions that organisms must cope with, the kinds of environments created by the interaction of organisms with one another and their physical surroundings, and the complexity of such systems.
Begin the lesson with a brief discussion about what students perceive to be the benefits, if any, of biodiversity. You might want to record some of these ideas down on chart paper so that students can compare these early, naïve ideas with those following instruction. Students may express some of these misconceptions about biodiversity:
- Biodiversity of other species is not relevant to humans.
- Biodiversity loss on the earth is inevitable.
Now have students use their Biodiversity and Health student esheet to go to Understanding Biodiversity to refresh their knowledge and get background information on biodiversity. Students can refer to this resource whenever they feel they need to refresh their understanding of the topic.
Using the student esheet, students will explore the benefits of biodiversity, particularly as it relates to human health. To do this, they will go to and read these articles:
- Tipping the Scales: The Delicate Balance Between Microbes and Man
- How Ecosystem Disturbance Affects The Spread of Disease
- Human Activity Is Rocking the Boat
Once students have read the articles, they should write a paragraph in response to each of these questions:
- According to the article “Tipping the Scale: The Delicate Balance Between Microbes and Man,” what are the benefits of biodiversity?
- How can a change in the environment lead to a change in disease behavior?
- What role does human activity play in environmental changes that affect biodiversity?
Ask students to share their answers with the class. Discuss and review what students have learned. To summarize the discussion, ask students to reflect generally on these ideas:
- How is biodiversity beneficial to human health?
- Can the disruption of ecosystems affect your health? Explain your answer.
Have students write an essay in which they explain the possible effect of human activities on the emergence of “new” diseases and the resurgence of established ones with regards to these issues:
- Climate Change
- Travel, Migration, and International Trade
- Warfare and Social Disruption
The student essays should demonstrate that they can use explicitly stated information from grade-level texts to make and support interpretations, connect ideas within a text, identify and evaluate relevant information, and make simple inferences. Students should be encouraged to describe and evaluate how the information was presented in the articles.
Biodiversity and Human Health, from the Environmental Protection Agency, provides coverage of the issues presented in this lesson.
The Center for Biodiversity and Conservation, of the American Museum of Natural History, helps advance scientific research in diverse ecosystems and strengthens the application of science to conservation practice and public policy.
AAAS Atlas of Population and the Environment is a website that contains the text for the book published by AAAS. The AAAS Atlas of Population and Environment is an important analysis of the relationships between human population and the environment. Illustrating through text, maps, and diagrams how population affects the world's ecosystems and natural resources both in the short and long term, the Atlas brings together a wealth of information from the most up-to-date sources.