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