Fish with Feet: Media's Missing Links

Shawn Gould, ©National Geographic SocietyIt was just a month ago that the world's media outlets fell over themselves proclaiming the fossil findings of a half-fish - half vertebrate as the Missing Link -the Smoking Gun of fossil evidence that finally starts to fill in those notorious "gaps" in the fossil evidence so gleefully pounced on by creationists and intelligent designists.

For the most part, the scientific community is far more reticent about the Missing Link claim for the Tiktaalik - the name given to the species whose fossils were discovered on Ellesmere Island - preferring the more sobering "transitional" (See Newfound Fossil Is Transitional between Fish and Landlubbers at Scientific American News.)

How could the media resist - Tiktaalik is already a star, with a wikipedia page, and its own web site at the University of Chicago?

While the Tiktaalik find does provide a tantalizing clue on how and when the fish/tetrapod transition occurred, it is always true that plugging a gap introduces two more gaps between the existing fossils and the "Missing Link." Is it a shock then that creationists and ID'ers aren't impressed? Doubling the gaps will always work to their advantage.

After the national build-up over the Dover trial, I was somewhat surprised that most of the articles appearing about the fossil find did not discuss how ID'ers or creationists reacted to the news. After reading an excellent Wall Street Journal piece by Sharon Begley on the finding and the reactions, I'm even more disturbed that more journalists did not "cover the controversy", as the ID'ers chant. Begley quotes John Morris of the Institute for Creation Research - Tiktaalik "is just a variety of fish. There is still a huge gap [between fish and land-dwellers] that has to be filled."


Tiktaalik RoseaeOf course, I am mixing the creationists and ID'ers - something that the ID community tries awfully hard to disengage from, and maybe in this case there is a difference. With creationists openly believing that there are no transitional forms (because every species is created), Tiktaalik can only be understood as a divine intervention, and Morris' quote is disingenuous at best - no creationist believes, or desires, that the new "gaps" be filled. I am guessing that ID'ers want the opposite. If the "gaps" are filled in, then there isn't such a large complexity-distance between fish and land-dweller, and divine intervention does not need to be called upon to explain the extra complexification now present in the fossil record.

And now back to the popular media, who pushed the Missing Link angle, but mostly ignored the reactions of the anti-evolution camps and the ramifications for future Dover situations. As in the articles that proliferated around the time of the Dover ruling, the popular Media again lost the chance to deliver an important lesson -namely what is science, and what isn't. Tiktaalik can be understood in terms of evolution, and predictions can be made about future fossil finds from the same period and in the same geographical region. This understanding and prediction (there I go again with the magic double-edged sword of modeling in chaos, fractals, and everything else) are the hallmarks of a real theory. All that creationists and ID'ers can do is claim that there is still something left to be explained, and therefore nothing is explained.

The presence of a creature as odd as a Tiktaalik not only cries for an explanation, it is itself an explanation of how we all emerged from the sea, taking our first baby steps on scrawny, ugly flippers. Creationists and ID'ers can't deny Tiktaalik's existence, and they sure can't explain it either. Evolution can, and does.

The popular media again missed the big link - between creationism, intelligent design, and their lack of scientific substance. In trying to explain the sui generis Tiktaalik, well, they are theories that just "aint got legs."

(Illustration of Tiktaalik by Shawn Gould, ©National Geographic Society)

Comments

[Matt Myerson]

The pectoral fin of Tiktaalik and the origin of the tetrapod limb are closely linked. Wrists, ankles and digits distinguish tetrapod limbs from fins, but direct evidence on the origin of these features has been unavailable. The origin of limbs probably involved the elaboration and proliferation of features already present in the fins of fish such as Tiktaalik.
Tiktaalik
An interesting read of A Devonian tetrapod-like fish and the
evolution of the tetrapod body plan by Edward B. Daeschler1, Neil H. Shubin2 & Farish A. Jenkins Jr3

[Big Don]

So, could you use Chaos Theory in predicting the probability of finding a missing link? If you make some assumptions about time spans and the number of possible variations from a generation and the probability of survival and reproduction (etc.), could a model be created to do that?

[Rich DiDio]

Big Don - You could certainly model this, but it wouldn't need anything fancy from Chaos Theory. Just basic probability.

[Rich DiDio]

Matt - thanks for pointing out the "links" between the fins and limbs.

Daeschler, et. al. are the ones who found the fossil...