1. End Show Slide 1 of 35 Mr. Karns Biodiversity

2. End Show Slide 2 of 35 6-3 Biodiversity

3. End Show 6-3 Biodiversity Slide 3 of 35 The Value of Biodiversity Biological diversity, or biodiversity, is the sum total of the genetically based variety of all organisms in the biosphere. Ecosystem diversity includes the variety of habitats, communities, and ecological processes in the living world.

4. End Show 6-3 Biodiversity Slide 4 of 35 The Value of Biodiversity Species diversity is the number of different species in the biosphere. Genetic diversity is the sum total of all the different forms of genetic information carried by all organisms living on Earth today.

5. End Show 6-3 Biodiversity Slide 5 of 35 The Value of Biodiversity Why is biodiversity important?

6. End Show 6-3 Biodiversity Slide 6 of 35 The Value of Biodiversity Biodiversity is one of Earth's greatest natural resources. Species of many kinds have provided us with foods, industrial products, and medicines—including painkillers, antibiotics, heart drugs, antidepressants, and anticancer drugs.

7. End Show 6-3 Biodiversity Slide 7 of 35 Threats to Biodiversity What are the current threats to biodiversity?

8. End Show 6-3 Biodiversity Slide 8 of 35 Threats to Biodiversity Human activity can reduce biodiversity by: altering habitats hunting species to extinction introducing toxic compounds into food webs introducing foreign species to new environments

9. End Show 6-3 Biodiversity Slide 9 of 35 Threats to Biodiversity Extinction occurs when a species disappears from all or part of its range. A species whose population size is declining in a way that places it in danger of extinction is called an endangered species. As the population of an endangered species declines, the species loses genetic diversity.

10. End Show 6-3 Biodiversity Slide 10 of 35 Habitat Alteration When land is developed, natural habitats may be destroyed. Development often splits ecosystems into pieces, a process called habitat fragmentation. The smaller a species’ habitat is, the more vulnerable the species is to further disturbance.

11. End Show 6-3 Biodiversity Slide 11 of 35 Demand for Wildlife Products Throughout history, humans have pushed some animal species to extinction by hunting them for food or other products. Today, in the U.S., endangered species are protected from hunting.

12. End Show 6-3 Biodiversity Slide 12 of 35 Demand for Wildlife Products The Convention on International Trade in Endangered Species, CITES, bans international trade in products derived from endangered species.

13. End Show 6-3 Biodiversity Slide 13 of 35 Pollution Many forms of pollution can threaten biodiversity. One of the most serious problems occurs when toxic compounds accumulate in the tissues of organisms. DDT, one of the first pesticides, is a good example of this.

14. End Show 6-3 Biodiversity Slide 14 of 35 Pollution For a long time DDT was considered harmless, and it drained into rivers and streams in low concentrations. However, DDT has two hazardous properties: It is nonbiodegradable, which means that it cannot be broken down by organisms. Once DDT is picked up by organisms, it cannot be eliminated from their bodies.

15. End Show 6-3 Biodiversity Slide 15 of 35 Pollution When DDT enters food webs, it undergoes biological magnfication. In biological magnification, concentrations of a harmful substance increase in organisms at higher trophic levels in a food chain or food web. In 1962, biologist Rachel Carson wrote Silent Spring, which alerted people to the dangers of biological magnification.

16. End Show 6-3 Biodiversity Slide 16 of 35 Pollution Magnification of DDT Concentration

17. End Show 6-3 Biodiversity Slide 17 of 35 Pollution Magnification of DDT Concentration

18. End Show 6-3 Biodiversity Slide 18 of 35 Pollution Magnification of DDT Concentration

19. End Show 6-3 Biodiversity Slide 19 of 35 Pollution Magnification of DDT Concentration

20. End Show 6-3 Biodiversity Slide 20 of 35 Pollution Magnification of DDT Concentration

21. End Show 6-3 Biodiversity Slide 21 of 35 Pollution Magnification of DDT Concentration

22. End Show 6-3 Biodiversity Slide 22 of 35 Pollution The widespread use of DDT threatened populations of many animals—especially fish-eating birds like the bald eagle—with extinction. By the early 1970s, DDT was banned in the U.S. and in most other industrialized countries; as a result, affected bird populations have recovered.

23. End Show 6-3 Biodiversity Slide 23 of 35 Introduced Species Another threat to biodiversity comes from plants and animals that humans transport around the world either accidentally or intentionally. Invasive species are introduced species that reproduce rapidly because their new habitat lacks the predators that would control their population.

24. End Show 6-3 Biodiversity Slide 24 of 35 Introduced Species Hundreds of invasive species—including zebra mussels in the Great Lakes and the leafy spurge across the Northern Great Plains—are already causing ecological problems in the United States.

25. End Show 6-3 Biodiversity Slide 25 of 35 Conserving Biodiversity Conservation is the wise management of natural resources, including the preservation of habitats and wildlife.

26. End Show 6-3 Biodiversity Slide 26 of 35 Conserving Biodiversity Strategies for Conservation Many conservation efforts are aimed at managing individual species to keep them from becoming extinct.

27. End Show 6-3 Biodiversity Slide 27 of 35 Conserving Biodiversity What is the goal of conservation biology?

28. End Show 6-3 Biodiversity Slide 28 of 35 Conserving Biodiversity Conservation efforts focus on protecting entire ecosystems as well as single species. Protecting an ecosystem will ensure that the natural habitats and the interactions of many different species are preserved at the same time.

29. End Show 6-3 Biodiversity Slide 29 of 35 Conserving Biodiversity Conservation Challenges Protecting resources for the future can require people to change the way they earn their living today. Conservation regulations must be informed by solid research and must try to maximize benefits while minimizing economic costs.

30. End Show - or - Continue to: Click to Launch: Slide 30 of 35 6-3

31. End Show Slide 31 of 35 6-3 The type of biodiversity that includes the inheritance information carried by the Earth’s organisms is called a.biological magnification. b.ecological diversity. c.genetic diversity. d.species diversity.

32. End Show Slide 32 of 35 6-3 Populations of invasive species tend to a.decrease. b.increase rapidly. c.remain constant. d.increase, then decrease.

33. End Show Slide 33 of 35 6-3 The wise management of natural resources, including the preservation of habitats and wildlife, is known as a.biodiversity. b.conservation. c.habitat alteration. d.ecosystem diversity.

34. End Show Slide 34 of 35 6-3 By focusing on protecting specific ecosystems, biologists hope to preserve a.global biodiversity. b.biological magnification. c.invasive species. d.habitat fragmentation.

35. End Show Slide 35 of 35 6-3 In a food pyramid, biological magnification results in the a.increased amount of a toxic substance in organisms at the lowest level. b.increased amount of a toxic substance in organisms at the highest level. c.decreased number of levels in the food pyramid. d.increased amount of a toxic substance in the surrounding air or water.

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