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Re: Earth's wobble killed off mammal species



Ian Paulsen writes:

 I read somewhere that the average species span for a Pleistocene mammal
was 900,000 years. Longer for a Pleistocene bird. Does this mammalian
species span hold true for all time periods?

I get the impression that the 2-3 million year value is a very general average. I'd expect the average to go down during times of rapid climatic change, and possibly even increase during long periods of stability.


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Dann Pigdon
GIS / Archaeologist         http://heretichides.soffiles.com
Melbourne, Australia        http://www.geocities.com/dannsdinosaurs
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