1. Ch 10 Biodiversity

2. 10.1 A world rich in Biodiversity
Biodiversity is short for “biological diversity” which is the number of different species in a given area.
1.the variety of organisms in a given area
2.the genetic variation within a population
3.the variety of species in a community
4.the variety of communities in an ecosystem
Ex- Tropical Rain forest has an extraordinary number of species.

3. What we do know… 1.7 million known species – mostly insects
Actual number of species on Earth is unknown
Possibly 10 million if we had the undiscovered number from deep in the ocean, remote wilderness, and even in cities.

4. Unknown Diversity

5. Levels of Diversity species diversity ecosystem diversity
Biodiversity can be studied and described at three levels:
species diversity
ecosystem diversity
genetic diversity
Genetic diversity refers to all the different genes contained within all members of a population.

6. Benefits of Biodiversity
1. Stability of ecosystems
2. Sustainability of populations
3. Use and benefit from the variety of
life forms

7. Species Are Connected to Ecosystems
Every species is probably either dependent on or depended upon by at least one other species in ways that are not always obvious.

8. Keystone Species
A keystone species is a species that is critical to the functioning of the ecosystem in which it lives because it affects the survival and abundance of many other species in its community.
An example is the sea otter.
The loss of the sea otter populations led to an unchecked sea urchin population, which ate all the kelp leading to the loss of kelp beds along the U.S. Pacific Coast.

9. Genetic Diversity. Is it important?
It is critical to a species survival!
The more diverse, the greater the likelihood it will survive environmental changes.
Small & isolated populations likely to crash

10. Bottlenecking
When a population shrinks, its genetic diversity decreases (as if going through a bottleneck)
Even if it grows again, it will reduce its genetic diversity
This may cause members to inherit genetic diseases.

11. Who cares about biodiversity?

12. More reasons biodiversity is important…Medical and Industrial Uses
We use the variety of organisms for food, clothing, shelter, and medicine.
Ex’s:
1. ¼ of Prescription drugs in U.S. are from plants
2. Most antibiotics are from chemicals in fungi.
3. chemicals and industrial materials

13. Common medicines and medical uses derived from plants

14. Agricultural Uses of Biodiversity
Most new crop varieties are hybrids, or crops developed by combing genetic material from other populations
History has shown that depending on too few plants for food is risky.

15. Ecotourism
Ecotourism is a form of tourism that supports the conservation and sustainable development of ecologically unique areas

16. 10.2 Biodiversity at risk
The extinction of many species in a relatively short period of time is called a MASS EXTINCTION.
HUMANS are the primary cause of extinctions.

17. Who’s most susceptible?
Large Populations that adapt easily to many habitats are NOT likely to become extinct.
Small populations in limited areas can easily become extinct.
Species that are especially at risk of extinction are Migrating species, and those that need large or special habitats, and those that are exploited by humans

18. 10.2 Biodiversity at Risk Endangered Threatened
= species that is likely to become extinct if the protective measures implemented are not taken immediately.
Threatened
= species that has a declining population and that is likely to become endangered if not protected.

19. How Do Humans Cause Extinctions?

20. How do humans cause extinction?
4 main human reasons for extinctions:
1. destruction of habitats
2. introduction of nonnative species
3. Overhunting, poaching
4. pollution

21. 1. Habitat loss
75% of extinctions now occurring due to habitat loss Panthers in florida Only 100 left in florida Due to: canals, roads, fences

22. 2. Invasive exotic species
= species NOT native to area
Native species do not have natural defenses against exotic species.

23. 3. harvesting, hunting, and poaching
Ex – 2 billion passenger pigeons were hunted to extinction in ’s. Can be sold as pets, houseplants, wood, food, or herbal medicine. POACHING – illegal hunting, fishing, harvesting and trade of wildlife since for poor countries they are sources of food, medicine, or income.

24. 4. pollution
Pesticides, cleaning agents, drugs, and other chemicals used by humans make their way into food webs around the globe.
Ex- DDT and the bald eagle

25. The most threatened areas of high species diversity on Earth has been labeled BIODIVERSITY HOTSPOTS and include mostly tropical rainforests, coastal areas, and islands.
The hotspot label was developed by an ecologist in the late 1980s to identify areas that have high numbers of endemic species but that are also threatened by human activities.
Most of these hotspots have lost at least 70 percent of their original natural vegetation.

26. Biodiversity Hotspots

27. 10.3 The Future of Biodiversity
Saving one species at a time 1. Capture and breeding programs 2. zoos, aquariums, parks, gardens 3. More study needed

28. Germ Plasm
Form of genetic material (reproductive, or germ, cells of plants and animals)
Can be stored in the form of seeds, sperm, eggs, or pure DNA.

29. Preserving Habitats and Ecosystems
The most effective way to save species is to protect their habitats.
Small plots of land for a single population is usually not enough because a species confined to a small area could be wiped out by a single natural disaster. While other species require a large range.
to find adequate food.
Therefore, protecting the habitats of endangered and threatened species often means preserving or managing large areas

30. Legal Protection for Species
Many nations have laws and regulations designed to prevent the extinction of species, and those in the United States are among the strongest.
For example, in 1973, the U.S. Congress pass the Endangered Species Act.
The Endangered Species Act is designed to protect any plant or animal species in danger of extinction

31. U.S. Laws
Under the first provision of the Endangered Species Act, the U.S. Fish and Wildlife Service (USFWS) must compile a list of all endangered and threatened species in the United States.
As of 2002, 983 species of plants and animals were listed.
The second main provision of the act protects listed species from human harm.
The third provision prevents the federal government from carrying out any project that jeopardizes a listed species