Fossils Reveal Giant Predatory Octopuses Up to 19 Meters Long in Cretaceous Oceans

Fossilized remains of predatory octopuses from the Cretaceous period indicate these creatures may have been highly intelligent hunters, with one species potentially reaching up to 19 meters in length. During the Cretaceous, these octopuses swam the seas as apex predators, comparable to orcas or great white sharks among invertebrates.

@NewScientist reported that Yasuhiro Iba at Hokkaido University in Japan described them as large, intelligent and highly effective hunters.

Yasuhiro Iba and his colleagues examined 27 large fossilized octopus jaws dating to between 100 million and 72 million years ago. The jaws were collected in Japan and Vancouver Island, Canada. A dozen of these octopus jaws were new to science and had been locked inside rocks, revealed only through high-tech scanning equipment, digital fossil mining and artificial intelligence to image the remains hidden in the stone.

The octopus jaw, also called the beak, is made primarily of durable chitin, which allowed it to survive as a fossil while the soft-bodied animal did not. Previously, five species of octopus were thought to have lived in the Cretaceous Period. But the team found just two confirmed octopus species from the Cretaceous: Nanaimoteuthis jeletzkyi and N.

Haggarti. 'We realised early on that the jaws were unusually large,' Yasuhiro Iba stated. The jaws of N. haggarti stood out even when compared with large modern cephalopods. The team estimated N. 6 meters in total length.

These octopuses were animals over 10 meters long with long arms and powerful jaws capable of crushing hard structures. Nanaimoteuthis haggarti may have been among the largest invertebrates in Earth’s history. Cretaceous oceans were home to this octopus species that reached up to 19 meters in length.

Superficially resembling today’s giant squid (Architeuthis dux), which reach lengths of over 12 meters, the ancient octopuses were open-water swimmers. Squids typically have eight arms plus two long tentacles for prey capture, while octopuses have eight arms and rely heavily on them all to capture prey.

'Nanaimoteuthis likely used long, flexible arms to seize prey and then processed it with powerful jaws, rather than chasing prey in the same way as a squid,' Yasuhiro Iba stated.

The team analyzed the scarring and wear on the ancient jaws, finding evidence of processing hard materials such as large bivalves, ammonites, crustaceans, fish and other cephalopods. There is uneven wear of the jaws, possibly indicating lateralisation. 'In our fossils, asymmetric jaw wear suggests that these animals may have favoured one side during feeding,' Yasuhiro Iba stated.

John Long at Flinders University in Australia commented on the findings, noting that many creatures during this time experienced gigantism, with oceans full of food for large predators. aea6285. Fossilized remains suggest these predatory octopuses may have been highly intelligent hunters, with advanced behavior implied by potential lateralisation associated with increased brain complexity and efficient information processing.