One of the biggest myths of evolution is that it's always progressing. Evolution is a branching tree. New species do not arise as a result of a long-term goal.
Paleontologists unveiled a fossil that proved to be an antidote to the myth of progress. Our ancestors used to walk across mud flats with four limbs complete with wrists, knees, and elbows. The Qikiqtania wakei is a fossil from this line.
Our ancestors did not move to land. They didn't want to walk to swim again.
Neil Shubin is a paleobiologist at the University of Chicago This is not the case. Some species will land and others will return to the water.
In 2004, Dr. Shubin and his colleagues made a big discovery while searching for fossils. They found a fish that was close to land animals. It had four leg-like fins.
Our humerus, radius, ulna and wrist bones were found in the creature's front fins. The combination made it possible for the fish to walk on mud flats and the bottom of swamps.
The importance of Tiktaalik came into sharper focus when scientists put it on an evolutionary tree. Scientists were able to see how the body evolved by looking at the branches. The fish have long bones in their legs. The toes and fingers came up later.
Even before finding Tiktaalik, Dr. Shubin and his colleagues discovered a branch of our evolutionary tree with a fossil that they didn't know existed.
In 1998 the team was attracted to rocks that looked like fossils from the earliest days of thepods. One field season after another was disappointing.
There was something promising on a small hill next to the tents when the researchers came back in 2004. There was a field of white scales on dark rock that Dr. Shubin saw one day.
The scales were only found on fish that are related to thepods. The fish jaw fossil was found near the dark rock. The rock was the size of a frisbee and had bone-like specks on its surface.
The first fossils of Tiktaalik were found four days after Dr. Shubin took everything in a bag to his lab. After they got back to Chicago, they realized it was revolutionary.
It sat in a drawer because we were focused on Tiktaalik.
The researchers found at least 10 specimen of Tiktaalik. They were able to show the growth of the animal over the course of its life.
The walking style of Tiktaalik was reconstructed using the fossils. The animals hunted fish with their long fangs and sucked it down their throats.
The Frisbee rock was the focus of the research in 2019. High-resolution images of fossils, even when they are still in rocks, were produced by the University of Chicago with the use of a computed tomographic device. Thomas Stewart, a researcher in the lab, scanned the rock after scanning the jaw and scales.
He was surprised that it had a complete fin. Although it was similar to Tiktaalik's fin, it had some important differences that made it different from the others.
The doctor said that he could have been knocked over by a feather.
The researchers would rush to their lab to make sense of their discovery. The hidden fin was discovered by Dr. Stewart. Scientists were not allowed to work in their lab as the university closed due to the Pandemic.
June 2020 was when they were able to get back in. They took a better look at the bones inside by trimming some of the rock. Researchers pored over the images for a long time.
Dr. Shubin said that the project became a Pandemic Lock Down. We were sane when the world was not.
The Inuktitut names for the region where the fossil was found were Qikqtaaluk and Qikqtani. David Wake was a mentor to Dr. Shubin and died last year.
A careful comparison of its body parts confirmed that it was a close relative to Tiktaalik. It took a different path after it branched off from Tiktaalik. It was probably only about 30 inches long.
The fins of Qikiqtania changed dramatically.
The humerus on Tiktaalik and other fish had knobs and ridges. Qikiqtania had a smooth arm that didn't offer much support.
There was a striking difference in the elbow. Tiktaalik relied on its elbow to walk, bending its limb at a 90- degree angle into a push up position. The elbow was locked and the fin was straight.
The limb is like a paddle, according to Dr. Shubin.
A bigger fan of rays at the end of its fin may have aided in its swimming ability. It wouldn't have helped walkers.
According to Dr. Shubin, Qikiqtania decided to swim in the open water instead of walking due to the recent evolution of its ancestors.
Dr. Shubin pointed to the tetrapods that came back to the water. About 50 million years ago, land mammals adapted to being in the water. It was found that some of our ancient relatives gave up walking before walking evolved.
The bodies of its swimming ancestors were not returned to the water. The bite-and-suck attack is what the fish evolved to use. They are doing it in new ways and returning to the water as well.
A paleobiologist who was not involved in the new study said it was great to see us fill out the tree of life here. We don't have a lot of fossils that document the early stages of the evolution of the body plan.
Dr. Shubin's hypothesis will be tested by more fossils of Qikiqtania. It was not clear to her if the fin stuck straight out as a paddle or not.
She said that she would like to dig into the questions that come from the specimen.
Some of the Tiktaalik fossils that Dr. Shubin and his colleagues have are being reexamined to see if they are from Qikiqtania. They wonder if a fossil found in Scotland in the 1990s could be related to Qikiqtania's family.
For the first time in nine years, Dr. Shubin and his colleagues are going to go back to the North. They plan to dig for more fossils at Dr. Shubin's lunch spot. It's possible that they'll find more fish like the one pictured.
The doctor said he felt like a kid in a candy store waiting to get back in the store.
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