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Re: Back-evolution of limbs.

     Hello Jack , The thought I had in mind when I ask the question about digits
that the return to an aquatic environment and fins that the bone structure 
seems to

remain the same as it was when they were terrestrial , is this correct ?

Jack wrote:

> On Sun, 28 Jun 1998, Earl Wood wrote:
> > I would like to insert a question here........ was the original limb 
> > composed
> > of five digits
> > before going onshore , or developed after becoming terrestrial ?
> > Earl Wood
> > candles@jps.net
> >
> This is not so simple a question as it may, at first, appear if you are
> discussing basal tetrapods.  The original tetrapod, _Acanthostega_ or
> something related, possessed as many as eight digits.  However, it has
> been suggested that this animal never left the water and only used its
> digits to help it remain still while under water or to "crawl" along the
> bottom.  I don't know much a _Tulerpeton_ (sic?), but I have seen the
> monograph on _Ichthyostega_.  This animal possessed at least six digits
> and was probably a semiterrestrial form.  Therefore, the five-digit
> tetrapod limb probably did develop on land.
> Hope that I didn't miss the point of your question.
> Jack Conrad
> jconrad@lib.drury.edu

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