Fossilized Jaws Show Massive Octopuses Hunted in Dinosaur-Era Seas 100 Million Years Ago

New analyses of fossilized octopus jaws indicate that massive, kraken-like creatures hunted in the seas 100 million years ago during the age of the dinosaurs, @ABC reported. These ancient octopuses had eight arms and long bodies extending more than 60 feet (18 meters), rivaling the size of other carnivorous marine reptiles.

Researchers studied the jaws of 15 ancient octopus fossils previously found in Japan and Canada's Vancouver Island.

They also identified 12 more jaws from Japan using a technique called digital fossil mining, which scans rocks in cross-sections to reveal hidden fossils. By comparing these ancient jaws to those of modern-day octopuses, the team estimated that the creatures ranged from 23 to 62 feet (7 to 19 meters) in length.

The largest ancient octopus jaw was substantially bigger than that of any modern octopus, according to Yasuhiro Iba, a co-author and paleontologist with Hokkaido University.

These jaws, made of stiffened chitin, were tough enough to crush shelled and bony critters. The largest creatures' jaws showed significant wear and tear, including scratches, chips and rounded edges, suggesting the animals repeatedly crushed hard prey such as shells and bones, Iba said. ' The findings were published on Thursday in the journal Science.

Late Cretaceous-era waters were inhabited by sharp-toothed sharks, mosasaurs and plesiosaurs. Soft bodies of octopuses do not preserve well in the fossil record, making such discoveries rare. Neil Landman, a paleontologist with the American Museum of Natural History in New York who was not involved with the new research, noted the challenges in understanding ancient marine ecosystems.

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