>I reviewed your post regarding the Devonian fish to amphibian
>transitional sequence from August 28th. The data that you gave said the
>following.
>
>578-552 mya no gills, lungs present, legs present
>378 mya gills present, lungs present, lobe fins
>368 mya no gills, lungs present, 7 digit hind legs
>362 mya gills present, lungs present, 8 digit hind legs
>
>giving rise to amphibious Tetrapods... gills present, lungs present, 5
>digits or less today
Paul,
I don't know where you got the 368 MYR "no gills, lungs present 7 digit hind
leg." What I wrote was:
>368 MYR-Ichthyostega-- much like Acanthostega but has 7 digits on his
>hindlimb. He has lungs. His legs were only good for being in water. They
>could not support his weight. (Coates and Clack, 1990, p. 67)
Am I not correct that this is what I wrote and that you have not cited it
correctly? Check the archive if you have doubt. I wrote of Acanthostega:
>362 MYR- Acanthostega- has four legs, lungs but still has gills. (Coates and
>Clack , 1991, p. 234) He has 8 digits on his front leg. His legs could not
>support his weight either. (Coats and Clack, 1990, p. 66-67). He has fishlike
>lower arm bones (Coates and Clack 1990, p. 67)
Note that I clearly stated that Acanthostega had gills and lungs. The
gill-less state was not found until 358 MYR ago. I do not know where you got
the idea that there were no gills at 368 MYR but it was not from me. As I
indicated here:
>558-552 MYR A fossil found in Pennsylvania which is the second oldest
>amphibian, has only lungs and no gills and is fully capable of walking on
>land. (Washington Post, 117:(239): A2, Mnday Aug. 1, 1994)
Have you read the original articles I cited? I would strongly suggest that
you do so because you are missing several important pieces of information.
Going through these point by point you wrote:
>578-552 mya no gills, lungs present, legs present
I never gave a 578-552 mya entry so you could not have gotten this from me. I
gave a 558-552 Myr entry with these values. 558-552 should be at the end. You
need to read things more carefully.
>378 mya gills present, lungs present, lobe fins
You left off the fact that during this time the panderichthids only had 4 fins
(all other fish had dorsal and anal fins) These four fins were where the
limbs are on tetrapods.
>368 mya no gills, lungs present, 7 digit hind legs
You didn't get this correct either. The 368 had gills. I said this was much
like the acanthostega. They had gills also.
>362 mya gills present, lungs present, 8 digit hind legs
Unfortunately you got this wrong also. The 8 digits are on the forelimbs.
This is why you should read the original literature rather than trying to do
things by the seat of your pants. There are NO known complete hindlimbs for
the Acanthostega! No one knows how many digits were there.
M.I. Coates and and J. A. Clack write:
"There are no complete hindlimbs so far known for Acanthostega but the femur,
tibia and fibula are similar to those of Ichthyostega." "Polydactyly in the
earliest known tetrapod limbs." Nature 347: p. 67
Because of this, your conclusion:
>
>If your data is correct this shows oscillation rather than transition,
>and is not as smooth as Stephen wisely noted. It can also be interpreted
>as existing created diversity seen in sedimentary deposits at relative
>points in time. It can be utilized by Steve Jones PC approach because of
>the distinct and sudden appearance. A host of models can incorporate it,
>but I believe that it is a poor proof of evolutionary transition.
is based upon highly flawed data that was not at all what I wrote. My data
was correct. Yours wasn't.
glenn
Foundation,Fall and Flood
http://members.gnn.com/GRMorton/dmd.htm