Giant octopuses redefined Cretaceous oceans

What's happened

New fossil jaws and digital imaging reveal octopuses that measured up to 19 metres, rivaling mosasaurs and plesiosaurs as top predators in late Cretaceous seas. The findings, based on beak wear and jaw size, suggest large, intelligent cephalopods hunted hard prey and shaped ancient ecosystems.

What's behind the headline?

Analysis

The research shifts the axis of the late Cretaceous food web away from vertebrate dominance toward giant cephalopods.
The study relies on non-fossilized soft-tissue preservation challenges, using beaks as a proxy for body size and predatory behavior.
Lateralized wear on beaks hints at complex cognition and hunting strategies that may rival modern cephalopod behavior.
The use of digital fossil mining enables discovery of hidden jaws, expanding evidence without new excavations.
Implications include revising models of marine ecosystems and predator-prey dynamics for that era.

Forecast: Expect further finds that refine the size estimates and dietary range of these giants, potentially revealing broader cephalopod diversity in the era.

How we got here

Paleontologists re-examined beaks from 15 octopus-related fossils and identified 12 more using digital fossil mining. The work, published in Science, builds on earlier ideas that marine life during the Cretaceous was vertebrate-dominated. The study focuses on Nanaimoteuthis species from Japan and Canada’s Vancouver Island, dating 72–100 million years ago.

Our analysis

The Guardian, The Independent, Ars Technica, NY Post, The Science reporting outlets (Science) with contributions from Yasuhiro Iba (Hokkaido University) and Shin Ikegami; recent journal Science publication.

Go deeper

Could more giant cephalopods exist undiscovered in other regions?
What does this mean for the role of vertebrates in the late Cretaceous food web?
How might this change our understanding of cephalopod intelligence in deep time?