Fergus County, Montana, was no stranger to monsoons 328 million years ago when they first appeared on the scene. It used to be a marine bay, similar to the Bay of Bengal in South Asia, and it was a popular fishing destination. Tropical storms inundated the bay with freshwater and fine sediments on a regular basis, promoting algae blooms and depleting the water’s oxygen in certain areas. Anything that died in one of these locations may have the unusual posthumous good fortune of being preserved in its original condition.
Because the soft, squishy body of an ancient octopus was buried and preserved in these waters, it is preserved in perfect condition. A palaeontologist from New York’s American Museum of Natural History found the fossil’s intact arms after it was transferred to the Royal Ontario Museum in Canada in 1988. The fossil had been sitting in a drawer for decades until Christopher Whalen took it out of a drawer and saw them. When he examined the granite with a microscope, he saw little suckers dimpling the surface.
Dr. Whalen was intrigued and decided to investigate the fossil, anticipating that it would be similar to other cephalopods discovered in the Montana limestone. However, it turned out to be something completely different than expected. As a result of the discovery, Dr. Whalen and his colleagues believe that the fossil represents the earliest known progenitor of the vampyropods, an order of animals that includes vampire squids and octopuses, and that this pushes the earliest evidence of the group back by 82 million years. Described in an article published Tuesday in the journal Nature Communications by Dr. Whalen and Neil Landman, a retired curator from the museum, the new species is a hybrid of two previously described species.
According to Dr. Whalen, they named it after President Joe Biden in honour of his inauguration as president and because they were “encouraged by his promises to combat climate change and to finance scientific research,” as he put it in an email to me. Mr. Biden is neither the first president to have a species named after him, nor is he the first to have a species named after him. Donald J. Trump is the name of a caecilian that looks like a worm, as well as a moth with a golden crown of scales on its back. A total of nine species, including various fish and a lichen, have been named after President Barack Obama.
The unique fossil, which has ten arms, is the earliest known cephalopod to have suckers on its arms, and it is the first to be discovered. Compared to earlier generations, modern squids and cuttlefish have 10 arms, whereas octopuses have eight. Vampire squids (which are not really squids, but rather near cousins of octopuses) have eight arms and two stringy filaments, which are assumed to be remnants of their former arms, on their backs. As a result, the 10-armed S. bideni demonstrates that all cephalopods formerly had ten arms, before they were reduced to filaments and eventually extinct.
Dr. Christian Klug, a palaeontologist from the Swiss University of Zurich who was not engaged in the current study, stated his concerns about the findings. He believes the fossil most likely represents a specimen of Gordoniconus beargulchensis, a recognised species of ancient cephalopods from the Cretaceous period. Dr. Klug and Dr. Landman collaborated on a research on the anatomy of G. beargulchensis that was published in 2019.
As Dr. Clements, who was not engaged in the study and did not write the report, pointed out, the new work is mainly reliant on visual ways of analysis, and these issues may be answered by chemical investigations. “We would absolutely have more hints or a lot more answers if we had a whole suite of procedures,” he added, stressing that these techniques may be prohibitively costly to implement.
In his first examination of the fossil, Dr. Whalen sought to find evidence of the phragmocone, a chambered shell found in the shells of most ancient cephalopods that aids in the control of buoyancy. The phragmocone of a nautilus is its coiled shell; the phragmocone of a cuttlefish is its cuttlebone. Phragmocones have fossilised chambers that are split by mineralized sheets that are quite distinct and typically well-preserved, according to Dr. Whalen, who discovered the fossils.
Those unique sheets may still be seen in the fossil of G. beargulchensis, which is housed at the American Museum of Natural History, according to Professor Whalen. Because that fossil and S. bideni were both preserved at the same location and in the same habitat, the authors suggest that both should have retained lines. However, there was no evidence of these lines in S. bideni, indicating that the species never possessed an interior chambered shell.
A primordial rostrum, a mineralized counterbalance to guarantee that early cephalopods could swim horizontally, was also anticipated to be discovered, according to Dr. Whalen. However, the fossil of S. bideni lacked a rostrum, indicating that “it was never there to begin with,” according to Dr. Whalen.
Dr. Whalen, on the other hand, was not convinced. “Even if you disagree with our view that we are looking at gladius rather than a phragmocone and looking at a vampyropod rather than anything else, the measurements of the new fossil are unique enough to classify it as a new species,” he said.
Dr. Clements believes a future chemical investigation will confirm the existence of the suckers, which he said were hard to distinguish from the photographs included in the paper.
Dr. Whalen owes a debt of gratitude to the suckers, who may only have played a minor role in S. bideni’s narrative. ‘It had been languishing in a museum since the ’80s, and no one knew how significant it was,’ he said. “It was by coincidence that I saw the arm suckers that we realised how significant it was.”