Giant ancient octopuses hunted with dinosaurs, jaw fossils reveal

Researchers from Hokkaido University analyzed Late Cretaceous finned octopus jaws found in Japan and Vancouver Island using high‑resolution tomography and AI. They estimate these ancient cephalopods reached up to ~20 meters and were top predators alongside dinosaurs, with jaw wear indicating repeated, forceful predation on hard prey. This challenges the view that invertebrates were minor players in the Late Cretaceous marine ecosystems and suggests giant, apex invertebrate predators existed in that era.