Cretaceous Octopus Reached 19 Meters, Challenging 370 Million Years of Marine Predator Assumptions
Updated
Updated · 朝日新聞デジタル · May 22
Cretaceous Octopus Reached 19 Meters, Challenging 370 Million Years of Marine Predator Assumptions
2 articles · Updated · 朝日新聞デジタル · May 22
Hokkaido University researchers identified an octopus species up to 19 meters long that lived 86 million to 72 million years ago and likely ranked among the top predators in Cretaceous seas.
Twenty-seven fossil specimens from Japan and Canada—mainly preserved beaks—were analyzed with an AI-based digital fossil-mining method, letting the team estimate body size from beak dimensions.
Scratches and chips on the beaks point to a powerful bite, suggesting the animals preyed on hard-shelled shellfish and ammonites as well as fish.
The finding challenges the long-held view that large fish and other vertebrates dominated marine food chains for the past 370 million years, indicating invertebrate octopuses became some of the biggest carnivores in the Cretaceous oceans.
The study was published in Science, adding evidence that ancient octopuses may have exceeded modern giant squids in size.
How does a 19-meter octopus discovery rewrite the history of ancient ocean predators?
If AI can find a hidden sea monster, what other prehistoric giants are still concealed within rocks?