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e., caused by humans) mass extinction (2009). It is has been noted by scientists that it takes approximately 10 million years before biological diversity can even begin to get near what it existed before it died off. Over 10,000 scientists in the World Conservation Union have come up with data showing that "51% of known reptiles, 62% of known insects, and 73% of known flowering plants are in danger along with many mammals, birds and amphibians" (2009).
McKinney and Lockwood (1999) came up with a list of traits that influence whether species are "winners" or "losers" in a human-dominated world. Traits promoting range expansion were: selected traits (small size, high fecundity); high variability; widespread; rapid dispersal; generalist (eurytopy); and human commensalism. Some of the traits promoting extinction were: selected traits (large sixe, low fecundity); low variability; rare; slow dispersal; specialist (stenotopy); and poorly adapted to human activities (1999).
As was the case in other mass...
Past mass extinctions eradicated over 50% of all of earth's species and this would probably be the case in the next mass extinction. They also note that the definite winners would be a very small fraction of the earth's biotas -- perhaps 1 to 2% (1999). The replacement of so many losing species with a very small fraction of winning species will, they speculate, create a more spatially homogenized biosphere (1999).
References:
Biologists say planet is undergoing mass species extinction. Daily Galaxy. 2009.
Retrieved 27 Jul 2010 from:
http://www.dailygalaxy.com/my_weblog/2009/05/although-the-earths-islands-islands-make-up-less-than-four-per-cent-of-the-planets-land-mass-they-are-home-to-around-a-quart.html
McKinney, Michael L. & Lockwood, Julie L. (11 Nov 1999). Biotic homogenization: a few winners replacing many losers in the next mass extinction. Elsevier science,
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