1/17/2024 0 Comments Stone fish with legs![]() Tom Stewart holding a fragment of the newly described fossil fish Qikiqtania. But days later, the team found specimens of Tiktaalik and poured all their efforts into describing a fossil that would become famous for filling the evolutionary gap between fins and legs. Sure." The team returned to the site to fully excavate the fish later that afternoon. "Do I want to take a whole block back, you know, just for a couple scales?" he thought, before deciding: "What the heck. One rock, about the size of a brick, had just a couple of scales on the outside, and Shubin debated leaving it behind. He'd stumbled upon parts of a fossil fish: jaw parts and scales embedded in stone. While eating lunch near camp, Shubin, an author on the new paper, looked down and saw "a field of scales," he said. The team of paleontologists, which included Neil Shubin of the University of Chicago and Ted Daeschler of Drexel University’s Academy of Natural Sciences, had come to the Canadian Arctic for the sixth year in a row hoping to find a fish on the cusp of limbs. The single specimen of Qikiqtania was first unearthed in 2004, less than a week before the same group of scientists would uncover Tiktaalik at a nearby site. Qikiqtania "gives a richer picture of the diverse lifestyles and body plans that existed when the first vertebrates moved onto land hundreds of millions of years ago," Blob said. While some lineages kept evolving to move onto land, other lineages continued specializing in new ways in the water, according to Richard Blob, an evolutionary biologist at Clemson University who was not involved with the research. "It's not just an ancestor that kind of was halfway out of the water," said Tom Stewart, an evolutionary developmental biologist at Penn State University and an author on the new paper.Īs terrestrial organisms, we humans can bring our own bias into thinking that land is the place to be for anyone with a backbone. But evolution is extremely non-linear, and encompasses a bunch of animals doing many different, specialized things. "There is a classic image of humans evolving from apes that is often misinterpreted to mean that evolution is a 'march of progress,'" Kawano wrote in an email. Credit: Justin Lemberg and Tom Stewartįor us humans, it can be tempting to think of evolution as a path toward more complex, "better" species, according to Sandy Kawano, a researcher at the George Washington University, who was not involved with the new paper. The entire specimen of Qikiqtania wakei, reconstructed from scans. And the single specimen of Qikiqtania is much littler-about as long as a Chow Chow. Although the Qikiqtania (pronounced "kick-kiq-tani-ahh") is closely related to Tiktaalik, the nine-foot-long star of the water-to-land transition, Qikiqtania's fins appear much better suited for paddling than walking. Now, in a paper published Wednesday in the journal Nature, a group of scientists have described a new species of ancient fish, Qikiqtania wakei, that did just that. ![]() Why uproot everything for a chance with land when you had a good thing going? Instead, they would remain in water and mind their business. Unlike their famous cousins, these fish would not be some of the first colonists of the terrestrial world. But at some point, these fish evolved in a different direction, eschewing the ground and all kinds of bottoms for life in the open water. They may even have started evolving toward life on land without ever truly leaving the water, developing arm bones and musculature distinct from traditionally fan-shaped fish fins that might have helped them prop themselves up in the shallows. ![]() And some of these lineages of fish would boldly go where no fish had gone before, or at least where few fish had gone before, and over millions of years would make way for vertebrates to trample the lush realm of the terrestrial world and forever alter the course of evolutionary history by inventing sorbet (whee!) and the health insurance deductible (boo!).Īround the same time, other fish stayed put. Their fins evolved distinct adaptations, becoming less like fins and more like limbs. About 375 million years ago, ancient fish took their first awkward steps in the shallows and toward land.
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