Chapter 10 - Biodiversity

Biodiversity The number and variety of species in an area. short for biological diversity Earth has 1.7 million known species but think there could be as many as 10 – 50 million. Most known species are insects.

Levels of Diversity Biodiversity is studied and described in levels: 1. Species Diversity – this is the level commonly meant when referring to biodiversity. The study of differences in species/populations of species.

Levels of Diversity 2. Ecosystem Diversity – the study of different types of ecosystems and their ecological processes.

Levels of Diversity 3. Genetic Diversity – the study of genetic variation within populations.

Importance of Species Biodiversity 1. To Preserve Ecosystems Every species interacts in some way with other species. Some species are crucial to the functioning of an ecosystem. These are keystone species. 1880’s

Importance of Species Biodiversity 2. To Preserve Genetic Variation species with a high level of genetic diversity are better equipped to deal with ecological pressures such as drought or disease. When population numbers get really low a bottleneck occurs and only a limited number of genes survive. This lowers the chance for long-term survival of the species.

Importance of Species Biodiversity 3. To Be Used By Humans For Food For Shelter/Clothing For Recreation For Medicines Pacific Yew=Taxol for cancer treatment ¼ of all medicine comes from plants almost all antibiotics come from fungi

Loss of Biodiversity Extinction is a natural process. Over 90% of species that have ever existed are extinct- most without the influence of man When a large number of species die in a short period of time, it is called mass extinction. The mass extinction occurring now is different because it is being caused primarily by the actions of mankind.

Human Causes of Extinctions 1. Habitat Destruction Habitat Destruction accounts for 75% of extinctions. Because species are adapted to certain types of habitats, loss of those areas have caused the most extinctions.

Human Causes of Extinctions 2. Introduction of Exotic Species Moving species to areas they are not indigenous to (usually by humans). Rabbits in Australia Kudzu in Southern USA

Human Causes of Extinctions 3. Poaching The illegal hunting or harvesting of animals. Especially a problem in less developed countries. Can result in unintentional artificial selection

Human Causes of Extinctions 4. Pollution Can cause poisoning , suffocation, and many other life threatening issues for animals.

Areas of Most Concern 1. Tropical rainforests – are the most biologically diverse terrestrial biome, housing over ½ the world’s land species.

Areas of Most Concern 2. Coral Reefs/ Coastal Regions Extremely diverse ecosystem - threatened by coastal development and pollution

Areas of Most Concern 3. Islands Islands have few but distinct species. Have real problems with the introduction of exotic species. Brown Snake in Hawaii has driven many native birds to extinction.

Areas of Most Concern 4. Hotspots Places with large numbers of biodiversity but in danger from human activity Preservation of these regions would be the most effective way to slow the loss of biodiversity.

What’s Being Done 1. Captive Breeding Programs Capturing wild species to breed in captivity and then returning to the wild. The Giant Panda is also a species benefitting from captive breeding programs 9 California Condors remained in 1986. By 2002- 58 were released into the wild and 102 were living in captivity

What’s Being Done 2. Germ Plasm Banks The collection and preservation of genetic material in a controlled environment.

What’s Being Done 3. Zoos and Botanical Gardens Keeping live species for preservation, breeding, and education

What’s Being Done The Endangered Species Act The US has the toughest laws in the world regarding endangered species. Four Main Points: 1. The US Fish and Wildlife Service must compile a list of all Threatened/Endangered Species. 2. Threatened/Endangered Species may not be caught or killed, uprooted, or any part of them traded or sold. The only exception is if you have a permit that allows you to have them for study purposes. 3. Federal Government may not carry on projects that will jeopardize threatened/endangered species. 4. US Fish and Wildlife Service must develop a recovery plan for each threatened/endangered species.

The Ecosystem Approach Scientists advocate the preservation of entire ecosystems to protect biodiversity because a healthy biosphere requires intact ecosystems. By saving entire ecosystems, we save all species instead of individual species.

International Efforts to Protect Biodiversity Committee on International Trade of Endangered Species CITES - international ban on ivory 1989 Biodiversity Treaty signed at Earth Summit Rio 1992- to preserve species and habitats in many different countries.

Private Conservation Efforts WWF- The World Wildlife Fund The Nature Conservancy – buys land for preserves and sets up education programs Greenpeace – radical organization devoted to protecting species.

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