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Re: BCF and BADD



>In a message dated 95-11-28 13:05:22 EST, NKING.UCS@smtp.usi.edu writes:
>
>>I hate to be a pest (like now), but I'm sort of new to this group.  The=20
>>discussion of BCF and BADD is interesting, but what the heck are BCF and=
=20
>>BADD?  Like, what do the acronyms stand for?  Can someone explain the two=
=20
>>concepts in about ten words or less, each (really!)?
>>
>>
>
>BCF: Birds Came First.=20
>
>BADD: Birds Are Dinosaur Descendants.
>
>In BADD theory, it is argued that birds evolved from bipedal, cursorial
>theropods. In BCF, I argue that bipedal, cursorial theropods as well as
>modern birds evolved from a lineage of arboreal, birdlike ancestors. BADD
>says birds ran bipedally before they flew; BCF says birds climbed, glided,
>and flew but were always quite capable of running, either quadrupedally (in
>the early stages of the evolution of flight) or bipedally when grounded.

My turn to be a pest:-)

All this centers around the assumption that flight evolved in the trees;=
 from what I have read, the jury is still out on that one.  Now it could be=
 argued that the enlarged claw in dromaeosarus is a holdover from a=
 cursorial ancestor, but this could just be using circumstancial evidence. =
 What would happen to BCF and BADD if flight evolved on the ground?

Rob

***
Labrynthodonts: Amphibians that lived with the Minitaur!