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Re: dino numbers



In a message dated 95-10-08 03:33:49 EDT, bk090@freenet.carleton.ca (David
Brez Carlisle) writes:

>Thank you Dinogeorge for your thoughtful essay on this topic.
>I have a couyple of criticisms.  The first refers to the number
>of small dinos not fossilized.  My own observations in Alberta
>have shown vast numbers of teeth of small mammals in some of
>the bone beds, but none of small reptiles (I am old fashioned
>and still use this general name, despite the cladists).  This
>suggest to me that in this locality at least all the dinos
>were big boys, and the niches for small animals were filled
>by mammals.  That's small _vertbrates_ not small _animals_.
>
>

Late Cretaceous dino-birds were (conveniently enough) mainly toothless, so
guess what won't show up in the fossil record. Dan Chure, however, tells me
that the Morrison (Late Jurassic) is rife with very small teeth similar to
those of larger theropods. Dino-bird teeth? Most likely. Also, Late
Cretaceous arboreal and terrestrial small-animal niches were indeed filled up
with mammals, which were replacing/had replaced small dino-birds. Large
mammals replaced large dinosaurs following the K-T extinction event because
small mammals had already replaced the dino-birds during the Cretaceous. To
find good dino-bird remains, we must look not in Cretaceous sediments but
earlier. Alberta during the Late Cretaceous is not representative of the
entire world during the whole Mesozoic.