More about the Tiktaalik controversy

The axolotl [1] [2], a Mexican species that is critically endangered in the wild, bears a strong resemblance to Tiktaalik. The axolotl, classified as a salamander, develops lungs but retains gills and remains aquatic into adulthood and has digits on its limbs. Picture is from Wikipedia.

==========================================

This is a continuation of the article: A fish story: Your Fishy Inner Fish. Casey Luskin wrote,

. . . .the paper’s lead author, Catherine A. Boisvert, boasted in an interview with The Scientist that "it is now completely proven that fingers have evolved from distal radials already present in fish that gave rise to the tetrapod." Boisvert also praised her findings, stating: "The disposition of distal radials in Panderichthys are much more tetrapod-like than in Tiktaalik."

Confident that her fossil showed evolution better than Tiktaalik, Boisvert and other Darwinists then proceeded to admit striking criticisms of Tiktaalik: The interview with Boisvert at The Scientist states, "Previous data from another ancient fish called Tiktaalik showed distal radials as well -- although the quality of that specimen was poor. And the orientation of the radials did not seem to match the way modern fingers and toes radiate from a joint, parallel to each other." (emphasis added by Luskin)

An interview of Boisvert on a blog named "A Free Man" said,
.

AFM [A Free Man blog]: The creationist Discovery Institute has pounced on some of the statements in your paper regarding sample quality as evidence that scientists are trying to backpedal on previous hypotheses regarding digit development and evolution. Can you clarify your statements regarding sample quality of Tiktaalik and Panderichthys?

CB [Catherine Boisvert] : As you know, the “Discovery” Institute tactic is not to go to the primary literature in order to understand it but rather to use quotations from secondary, even tertiary sources, reorganise or use them out of context opportunistically to their own convenience. In this case, they used an article where the journalists unfortunately misunderstood me. Tiktaalik’s material is in fact exquisite, it is very well preserved, basically uncrushed and can be prepared out to be examined in three dimensions. I never said the quality was poor. I have simply explained that the morphology of the fin of Panderichthys is more tetrapod-like than that of Tiktaalik, which has nothing to do with the quality of the material.

But though Luskin did not cite the paper, he did use a primary source of sorts, the interview of Boisvert in The Scientist magazine. As noted above, Boisvert was quoted as saying, and I presume this is a verbatim quote,

"Previous data from another ancient fish called Tiktaalik showed distal radials as well -- although the quality of that specimen was poor. And the orientation of the radials did not seem to match the way modern fingers and toes radiate from a joint, parallel to each other."

Luskin said,

Darwinists are now praising Panderichthys for having features that are "much more tetrapod-like than in Tiktaalik," and are retroactively confessing weaknesses in their precious Tiktaalik, which is now admitted to be a fossil with a "quality" that was "poor."

IMO Casey misinterpreted the statement "the quality of that specimen was poor" as meaning that Tiktaalik is (1) poor as a transitional form between fish and tetrapods and/or that (2) the overall state of preservation of Tiktaalik was poor. However, as I noted before, though the Tiktaalik fossil may be a poor example of tetrapod-like limb development, Tiktaalik has other features that may be considered transitional between fish and tetrapods -- e.g., a bendable neck, a rib cage, and a flattened snout. Also, as before, IMO Casey Luskin was correct in saying that the "digits" on Panderichthys look more like bone fragments than like digits.

Anyway, IMO Tiktaalik is a greatly overrated fossil -- IMO it is not that much different from both living and extinct species. The axolotl shown above bears a strong resemblance to Tiktaalik.

Also, Panda's Thumb has an article about the Boisvert interview on the A Free Man blog.
.