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Re: BADD & BCF
In a message dated 95-12-06 15:14:41 EST, martz@holly.ColoState.EDU (Jeffrey
Martz) writes:
> It seems like there has been a little bit of coonfusion on the list
>(I know there is for me) regarding exactly what BCF and BADD are. I have
>personally been debating the bird origins problem from a general cursorial
>vs. arboreal origin perspective, and many or most others I think have
>been doing the same. However, I am under the impression that BCF
>and BADD do not just mean "trees down" or "ground up" in general, but really
>specific theories on ONE WAY an arboeal archosaur or ONE WAY a cursorial
>archosaur might develop flight. Just for the record, could someone lay
>out exactly and in detail the specifics of these two theories?
>
>
BADD ("Birds Are Dinosaur Descendants"): Birds evolved from certain bipedal,
cursorial theropods that became small and enlarged their forelimbs into
wings.
BCF ("Birds Came First"): Bipedal cursorial theropods were the flightless
offshoot descendants of small, arboreal, increasingly birdlike archosaurs
(dino-birds) that eventually evolved into birds. The small forelimbs of those
theropods were vestigial "wings."
You want more detail? For BCF, get a copy of _Mesozoic Meanderings_ #2.