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Re: Coelacanth article in current NatGeo



I think Choo is right. Chondrichthyans also have fleshy fins, thus
suggesting fleshy fins came first. Thus, the reason by which fleshy
fins were good may reduce to the reason by which fins are good. Now,
it may be asked why ray fins are more adaptive, if they persisted
because of intrinsic adaptive superiority and not because of luck at
the mass extinction (or because of other improvement in
actinopterygians).

2011/2/24 Erik Boehm <erikboehm07@yahoo.com>:
>> >  Maybe my understanding of
>> their diversity is wrong, but it seems odd
>> >  that at one point there were so many fleshy
>> finned fish, and now
>> >  there are almost none.
>>
>> A couple of mass extinctions.
>
> Of course, but prior to those, the lobe fins were not restricted to 
> bottom/river dwellers correct? if so, what purpose did those fleshy fins 
> serve?
>
> Its my understanding the basal lobe fins did not live in rivers, or along the 
> sea floor, where such fins may have been useful for holding the fish against 
> a surface. What was the original use?
>
>
>
>