Biodiversity

Biodiversity Outline Definitions 1. Biodiversity 2. Extinction I. Causes of Extinction 1. habitat destruction 2. hunting 3. exotic species II. Slow extinction 1. preservation 2. valuable products 3. aesthetic III. Endangered and Threatened species

Refers to the # and variety of species on earth. High biodiversity=many different plants and animals 1.4 million species identified by scientists Estimates range from 10-100 million Insects are more diverse than any other organism

Extinction When the last member of a species dies Most extinctions occur in the tropical rainforest b/c it is the most diverse biome The actions of humans are causing the extinction of plants and animals

How?? 1. Habitat destruction Destroy habitats to build homes, businesses and harvesting of trees for income Causes 75% of all extinctions Ex. Florida panther (type of cougar/ mountain lion)-one of the most endangered animals in N. America

#2. Hunting Not a major cause of extinction in countries with wildlife laws In developing countries it is a major problem *Poaching: illegal hunting of animals to take one or more of their parts For example: African elephant; rhinocerous

#3 Introduction of an exotic species Species not native to a particular area Can threaten native species which have no natural defenses against them For example: snakehead fish introduced in Virginia, Melalueca tree in Florida everglades

Kudzu

Why slow extinction? 1. To preserve ecosystems Ensure a healthy biosphere by regulating the flow of energy and cycling of nutrients

2. Loss of valuable products Approximately 40% of all prescription drugs used are made from living things Taxol comes from the Pacific Yew Plant and is an anticancer agent Loss of biodiversity will limit the development of future medicines

#3. Aesthetic Reasons Lose objects of fascination, wonder, and beauty

Endangered Species Act 1973 Designed to protect any plant or animal species in danger of extinction

Endangered Species Likely to become extinct in the near future if protective measures are not taken immediately In North America: red wolf, northern flying squirrel, jaguar (habitat destruction has caused them to move to S. America), green sea turtle, atlantic salmon, Florida manatee, brown bear

Threatened species: likely to become endangered if they are not protected the grizzly bear, gray wolf (on endangered list until Feb. 2009), polar bear (moved from endangered list in 2008) Bald eagle removed from list in June 2007