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a close up of an octopus under water

Photo by Oleksandr Sushko on Unsplash

Giant Octopuses Lived with the Dinosaurs

natureApr 29, 2026·277 words·3 min read

Scientists have found fossil evidence that the ancestors of today's octopuses were huge predators that swam alongside dinosaurs around 100 million years ago. A team from Hokkaido University in Japan, writing in the journal Science, says fossil jaws preserved in Late Cretaceous rocks show that these ancient octopuses grew to almost 20 metres long. That makes them as big as the largest marine reptiles of their time.

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