Biology 2483A Lecture Notes - Lecture 5: Extinction Vortex, Conservation Biology, Genetic Drift
9 Jun 2016
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Document Summary
Conservation biology: the study of phenomena that affect maintenance, loss and restoration of biodiversity applies principles of ecology to the protection of biodiversity. Scientific method calls for objectivity collection and interpretation without bias, but it is not free of human values. # of species on earth not currently known. Extinction rated determined from fossil records are used as background rates. (mammals/ birds: 1 species every 200 years avg species lifespan 1 million-10 million years but current rates 1/year avg 10k years. ) Estimates of extinction rate rely on: species-area relationship, changes in threat status of species and rates of pop. decline or range contraction of common species. Declaring a species extinct can stimulate search efforts. Small pops cannot serve the same function as large pops. Many guilds went extinct after colonization by polynesians on pacific islands. Introduction of species coincided with the range contraction of many native species.
