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Re: EARLY TETRAPODS (was Re: Back-evolution of limbs)



Concerning the idea that the basal tetrapods developed their "fingers" for
'rowing' along the bottom:

    All the evidence I've seen, indicates that the earliest tetrapods DID
use their limbs to propel themselves in shallow water, however two
additional points need to be made.

    One is that at least one early tetrapod (_Hynerpeton_) had a very strong
shoulder construction which might allow the animal to push its way out of
the water and walk on the tips of the budding phalanges.  (Not very
effectively, probably just enough to stick its head out of the water for
awhile).

    The other point is about one of the best known lobe-finned fish, the
_Ceolocanth_.  These fish have the lobes that most agree are equivalent to
the starting point for the tetrapod body plan.  (I am NOT counting number of
lobes here!)  However, these fish HOVER near the bottom of the sea, barely
moving a few inches above the bottom.  The depths are usually 300 feet or
more.  This sort-of argues against the shallow water only start for the
tetrapods.

        Allan Edels