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Biodiversity. Official video of the International Year of Biodiversity 2010 [www.keepvid.com].mp4. What is biodiversity?. The variety of life on Earth Includes wild and domesticated species, diversity of their genes, and the variety of ecosystems. Value of Wild Species.
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Official video of the International Year of Biodiversity 2010 [www.keepvid.com].mp4
What is biodiversity? • The variety of life on Earth • Includes wild and domesticated species, diversity of their genes, and the variety of ecosystems
Value of Wild Species • Instrumental value: a species of individuals organisms existence is beneficial (usually to humans) • Intrinsic value: a species or individual has value for its own sake, it does not need to be useful to us
Instrumental value • Ecosystem sustainability • Source of agriculture, forestry, aquaculture • Source of medicine • Recreational value • Aesthetic value • Scientific value • Commercial value – ecotourism
Intrinsic Value • Do species other than humans have inherent rights? • Organisms with no obvious value to humans have existed for thousands or millions of years and represent a unique set of biological characteristics
Decline of Biodiversity • Physical alteration of habitat (36%) • Exotic species introduction (39%) • Overuse (23%) • The Population factor • Pollution
How many species are there? • We have identified almost 2 million • Estimates are from 5 million to 100 million • Why don’t we know? • We have identified most organisms larger than a fly • Most work has been done in the developed world, but there are biodiversity hotspots • Recently discovered new species
Biodiversity Loss • Habitat Loss • Introduced species • Pollution • Population Growth • Over-consumption
Habitat Loss • Conversion • Natural areas are converted into farms, subdivisions, … • Fragmentation • Natural areas usually have large patches of land well connected to other patches • Simplification • Removing debris, managing forests for one species, channelization of streams
Introduced Species • Introduced, or exotic species, are not native to the area and have been deliberately or accidentally transported by human activity
Zebra Mussel Competes for food Hinders native clams Alters water clarity
Brown-headed cowbird Competes for food Nest parasite Harmful to neotropical migrants
European Starling Competes for food Competes for nesting holes, affecting native woodpeckers
Pollution • Creation of “dead zones” • Oil spills • Chemicals (ex. DDT) • Acid Deposition • Global Warming
Overuse/Overconsumption • Killing individuals of a particular species faster than they can reproduce will lead to the ultimate extinction of the species • Hunting • Trafficking in wildlife and products • Consumers • Exotic pet • Poor management of forests and woodlands