Octopuses the Size of School Buses Dominated Prehistoric Oceans --- A new study suggests 60-foot-long creatures resembling the mythical 'kraken' were top marine predators millions of years ago

 

 

“Paleontologists have long believed that giant reptiles ruled the oceans in the twilight of the dinosaur age. Now a new study in the journal Science suggests another apex predator dominated the food chain: school-bus-size octopuses resembling the mythical "kraken" monster.

 

These ancient invertebrates, or animals without backbones, lived during the late Cretaceous period, between about 100 million and 72 million years ago.

 

The larger of the two species described in the study could reach lengths of more than 60 feet, which dwarfs the largest invertebrate alive today, the giant squid, as well as predators like the modern great white shark. That suggests these prehistoric octopuses may be the largest invertebrates ever documented, according to a group led by Japanese researchers.

 

Invertebrates with soft bodies don't preserve as well in the fossil record as their back-boned counterparts. That leaves limited evidence for scientists to reconstruct their appearance and roles, said Yasuhiro Iba, a Hokkaido University paleontologist and co-author of the new study.

 

For octopuses like this, often one of the only things left behind is the beak, the jaw made of hard chitin -- the same material in lobster shells.

 

Iba's group uncovered 12 octopus jaws from the late Cretaceous period, and also re-examined 15 existing fossil jaws from ancient octopus relatives. They reinterpreted previously described fossil findings as belonging to one of two species: the smaller Nanaimoteuthis jeletzkyi, which was roughly 10 to 25 feet long, and the larger Nanaimoteuthis haggarti, between about 20 and 60 feet. Previously, Iba said, scientists thought some of these fossils belonged to vampire squids.

 

He and his colleagues looked at the relationship between jaw and body sizes in modern octopuses and used that information to estimate the size of the prehistoric predators.

 

The patterns of wear and tear on the fossil jaws indicate these creatures were biting into the shells and bones of prey -- including, perhaps, the other giant marine predators they were competing with, according to the study.

 

"They probably used their long, flexible arms to capture prey and their powerful jaws to crush hard parts," Iba said.

 

Some of the findings indicated these ancient octopuses were highly intelligent, like their modern-day counterparts, he added.

 

The wear on the fossil jaws was asymmetrical -- meaning the creatures may have favored one side over the other, a bit like handedness in humans. This characteristic is associated with advanced cognitive abilities in modern octopuses.” [1]

 

1. REVIEW --- Science Shorts: Octopuses the Size of School Buses Dominated Prehistoric Oceans --- A new study suggests 60-foot-long creatures resembling the mythical 'kraken' were top marine predators millions of years ago. Woodward, Aylin.  Wall Street Journal, Eastern edition; New York, N.Y.. 25 Apr 2026: C3.