Some 80 million years ago, the late Cretaceous oceans were patrolled by 17-meter mosasaurs, long-necked plesiosaurs, and massive, predatory sharks. For decades, the paleontological consensus was that this was the age of vertebrates; anything without a backbone was lunch.

During the Cretaceous, 19-metre-long predatory octopuses swam the seas, and evidence from their fossilised remains suggest they may have been highly intelligent hunters

Today's octopuses are intelligent, remarkably flexible animals that lurk in reefs, hide in crevices, or drift through the deep sea. But new research suggests that their earliest relatives may have played a far more predatory role in ocean ecosystems.