The ‘oldest octopus’ in the world isn’t an octopus after all, scientists find | CNN

The story of a 300-million-year-old fossil has been rewritten after scientists discovered that it doesn’t actually belong to the world’s oldest octopus as previously thought. In fact, it belongs to an animal related to a modern nautilus, which has tentacles and an external shell, according to a study published Wednesday in the journal Proceedings of the Royal Society B. “We basically used a wide selection of new analytical techniques to discover hidden anatomical characteristics within the rock,” lead study author Thomas Clements, a lecturer in invertebrate zoology at the University of Reading, England, told CNN on Thursday. “And we were able to determine that it is not an octopus, but is actually a very decomposed nautiloid, which is a relative of modern nautiluses.” The fossil, named Pohlsepia mazonensis, was found at the Mazon Creek site just south of Chicago, Illinois. Paleontologists had long been puzzled by the fossil as it is far older than the next oldest known octopus, which dates back about 90 million years. Clements explained that the animal had been decomposing for weeks before it was buried, giving its fossil an octopus-like appearance that led many scienti

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