Re: Age Abstractions

[Jeff Hecht <jeff@jeffhecht.com>]

At 11:53 AM -0600 6/20/07, franklin e. bliss wrote:

>
>Besides, I suspect that several non-avian theropod types did survive what ever 
>punctuated event that killed the majority of dinosaurian types.  They lingered 
>on in a new habitat with different ecological niches and new food chain 
>relationships until they weren't viable as a population any more.  Then they 
>followed their ancestors to the grave as a species.  Mammals jumped in and 
>filled the void.  I would be very surprised if several dinosaurian lineages 
>don't eventually pop up in Paleocene rocks lasting a few to hundreds of few 
>thousand years after the K/T boundary.  It all boils down into where is that 
>durned boundary.
>

I think it's quite possible that some individuals of some non-avian species 
survived the KT impact, but that their population densities were below the 
long-term survival threshold. If the impact reduced the population to a few 
dozen individuals spread over a large area, and also devastated the 
environment, you'd have a double whammy. First there are few individuals left 
to survive and reproduce. Many of those won't survive because their food 
sources are gone. You'd get a cascade of effects bringing down the whole 
dinosaur ecology. It would not be instantaneous; it might take a hundred or 
even a thousand years, and it would be worst for the larger critters. 

I wonder if somebody could model this?
-- 
Jeff Hecht, science & technology writer
jeff@jeffhecht.com  http://www.jeffhecht.com
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