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Re: Selective Extinction
Rob Meyerson wrote:
> Betty Cunningham writes,
> >birds, of course, survived, whereas pterasauroids did not so if you can
> >perhaps explain why?
> >Wehn Mt. St. Helens went off, birds that flew away survived, but still
> >had to deal with the ash that covered everything afterwards to search
> >for food and water.
> When we look at the major theories for the late-K mass extinction, all
>of them point to a heavily restrictive environment. To use the haymaker-
>impact scenario as an example, the resulting disruption of the land food
>chain will mean that food will be in short supply. Because of this,
>animals that can get by on small amounts of food will survive, which would
>include most ectotherms and smaller endotherms. Under this hypothesis,
>birds survived because they enhabited the "small endotherm" end of the
>scale, while the pterosaurs were in the "large endotherm" end.
> So, IMHO, birds survived simply because they were small.
Problem being that crocs (large ectotherms) survived while small dinos
(small endotherms) didn't.