Re: Babies and Ecology

[Dann Pigdon <dannj@alphalink.com.au>]

dbensen wrote:
> 
>     A while back, I said something about baby dinosaurs filling a different 
> niche as adult members
> of the same species.  I gave tyrannosaurs as an example, with little, 
> coelurosaur-like babies
> filling the small-predator niche (for a few months at least) while the adults 
> ate larger prey.  The
> idea was shot down as people found some rather large logical errors in it 
> (after all, the babies
> are only small for a short period), but I still think there is a grain of 
> truth in my idea.

It seems to me that, amongst theropods, the total lengths of adult
specimens tend to cluster around 1-3 metres and 6-12+ metres, with very
few adult predatory theropods having total lengths of between 3 and 6
metres (the only theropod groups that seem to bridge the gap are
ornithomimosaurs, that don't strike me as having been particularly
predatory - generalists more likely).

I've suggested in the past that this size gap may have been filled by
juveniles of the larger (6-12+ m) animals. Is there such a "size gap" at
all, or am I seeing patterns that just aren't there?

-- 
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Dann Pigdon                   Australian Dinosaurs:
GIS Archaeologist           http://dannsdinosaurs.terrashare.com
Melbourne, Australia        http://home.alphalink.com.au/~dannj/
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