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From: friesen@psivax.UUCP (Stanley Friesen)
Newsgroups: net.bio,net.origins
Subject: Re: Bipedalism (kind of long)
Message-ID: <1112@psivax.UUCP>
Date: Mon, 21-Apr-86 00:59:35 EDT
Article-I.D.: psivax.1112
Posted: Mon Apr 21 00:59:35 1986
Date-Received: Sun, 27-Apr-86 14:41:24 EDT
References: <487@bcsaic.UUCP> <1002@cybvax0.UUCP> <32@sphinx.UChicago.UUCP> <2529@jhunix.UUCP>
Reply-To: friesen@psivax.UUCP (Stanley Friesen)
Distribution: net
Organization: Pacesetter Systems Inc., Sylmar, CA
Lines: 27
Keywords: dinosaurs, bipedalism, hunting, escape
Xref: linus net.bio:267 net.origins:3007

In article <2529@jhunix.UUCP> (Thomas Richard Holtz) writes:
>
>Basically, the best palaeontological explaination for why dinosaurs were
>bipedal and most mammals aren't boils down to:
>
>	Why were most dinosaurs bipedal?
>		Because they evolved from bipeds (the thecodonts).
>
>	Why are so few mammals bipeds?
>		Because they evolved from quadropeds (the therapsids).
>
>I know it's not a very exciting answer, but don't complain to me.
>Complain to Mother Nature; she made the rules.  :-)
>
	Yes, quite correct, at least as far as we can tell with
current data. However this only moves the question back one step.
Why were thecodonts bepedal and therapsids quadrupeds?
Actually I think this may have a more "satisfying" answer. That is my
studies suggest that there were adpative reasons for the shift to
bipedalism among thecodonts. But I will refrain from saying what I
think until other people have had a chance to speak.
-- 

				Sarima (Stanley Friesen)

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