There are many speculations regarding evolution and how it took place. Many think of evolution as a linear timeline; but this is not always the case and such can be seen in creatures like the Qikitania and Tiktaalik.
The Qikitania Waeki was a fish resembling a giant eel. This eel-like fish roamed Earth around 375 million years ago. Its evolution allowed it to develop elbows, knees, wrists, and ankles in order to walk through mud flats. After analyzing their anatomy, scientists discovered that Qikitania Waeki did not continue walking on land. Instead, they began making their way back to the water.
Dr. Neil Shubin, a paleontologist at the University of Chicago, was one of the first to uncover fossils from the Tiktaalik, a related species known to be one of the first tetrapods or a four footed animal. As time went on, researchers found up to ten specimens of the Tiktaalik with a variety of ages. These specimens allowed scientists to determine the creature’s features along with the fact that they could grow up to nine feet long. The Tiktaalikk hunted fish using their long teeth shaped as fangs and they swallowed their prey whole.
Ongoing research showed that the anatomy of the Qikitania resembled the famous Tiktaalik. Qikitania diverged from its original evolutionary path and created its own. It shrunk down to only 30 inches long and there were more drastic changes to its fins. The Tiktaalik, which remained on the original path, showed that its humerus had knobs and ridges where its muscles could be relied on for support. In contrast, the Qikitania developed a more smooth humerus which decreased the support that the muscles relied on. Another notable difference appeared in their elbows: the Tiktaalik depended on its 90-degree elbows to walk but Qikitania fins extended out in a paddle-like manner.
There are many fascinating theories on how evolution works and because of these creatures, there more clarity on different trajectories of evolution. Researchers hope to uncover many more examples of evolution from our interesting past.
[Source: The New York Times]