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Re: Therizinosaurs and the Maniraptora

Dinogeorge wrote:
>I know that there are circumstances under which lost body parts can reappear
>in an individual, because such lost parts are retained in various early
>stages of embryological development and typically lost during later stages.
>When normal digital loss is retarded in the embryo, the digits will be
>expressed postnatally. This, however, is a pathological or congenital
>occurrence in isolated individuals that, like polydactyly, seldom if ever
>will spread through the entire species.
        Are you aware of Mr. Charles Darwin's quite extraordinary theory of
evolution by means of natural selection? Oh, you simply must hear of it!
        Mr. Darwin (cheeky old chap that he was) dared to speculate that
minor variations, such as your "pathological" or "congential" appearance of
lost body parts, might actually become prevalent in a population if they
were beneficial to the individuals possessing them! It is truly
extraordinary! Further, he seems to have thought that this follows rather
simply from the possibility that such variations might be both advantageous
and heriditable!
        So, you see my dear George, although you and I as reasonable men
could never believe such tripe, this fellow Darwin and several million of
his followers say that this is actually the origin of the anatomical
structures on animals we see today. How truly odd!
>it would have
>been nice if they had explained how they think segnosaur feet might have
>developed from typical theropod feet.
        I've written this until I'm jsut about blue in the fingertips:

>Segnosaurs aren't bullatosaurs, nor coelurosaurs, nor manuraptorans, nor
        ManIraptor. Sorry, priority rules. Alternatively, "Manuraptora" is
not defined.

>tetanurans, despite sharing a few minor, random characters here and there
>with each of those groups.
        I listed some 10 or so. Few of these were "random" (whatever a
random character is), none was minor (whatever that means).
        To use your own arguments against you, you could *not* explain the
similar selection pressures which might have casued the "convergences"
necessary to explaint the characters I and others have brought forth. On the
other hand, similarity of lifestyles and feeding habits very well justifies
considering the "synapomorphies" you list as convergences. And the "theropod
theory" can not only explain the therizinosaur foot, with anatomical
evidence that it is a reversal, but that very anatomical evidence cannot be
explained by your theory.

    Jonathan R. Wagner, Dept. of Geosciences, TTU, Lubbock, TX 79409-1053
               "Not the One..." -- Zathras (not Zathras)