Home: Scrying: Leaving the waves to walk on land

Leaving the waves to walk on land

April 06, 2006

Creationists who deny evolution by pointing out the lack of transitional forms in the fossil record can kindly put their feet in their respective mouths. Tiktaalik roseae, model and fossilFirst, we had Ambulocetus, the land-loving whale, then Archaeopteryx, the dinosaur-bird, and now, Tiktaalik, the walking fish. (Someone needs to start a series of bean-filled stuffed animals of these!)

Several fossil skeletons of the species were found in sedimentary rock formed in the Devonian age. When formed, the site was centered near the equator, providing a nice swampy habitat for Tiktaalik—today, the site is situated on Ellesmere Island, in the Canadian Arctic.

The creature had a number of features that placed it in between fish and land animals, including a neck that could swivel, and primitive versions of arms and hands:Tiktaalik: the missing link

Embedded in the pectoral fins were bones that compare to the upper arm, forearm and primitive parts of the hand of land-living animals. The joints of the fins appeared to be capable of functioning for movement on land, a case of a fish improvising with its evolved anatomy. In all likelihood, the scientists said, Tiktaalik flexed its proto-limbs mainly on the floor of streams and might have pulled itself up on the shore for brief stretches.

Since discovery, Tiktaalik has found his place on the evolutionary ladder:
In their report, the scientists concluded that Tiktaalik was an intermediate between the fishes Eusthenopteron and Panderichthys, which lived 385 million years ago, and early tetrapods. The known early tetrapods are Acanthostega and Ichthyostega, about 365 million years ago.

Tiktaalik, Dr. Shubin said, is “both fish and tetrapod, which we sometimes call a fishapod.”

For more on this fishapod, check out John Noble Winford’s article in the New York Times, which includes the full size originals of the images above, plus some unintelligible statements from creationists.