A famous Carboniferous fossil, Pohlsepia mazonensis, was long hailed as the oldest octopus, pushing the group's origin back 150 million years and anchoring molecular-clock estimates. Re-examination with synchrotron scans found none of the defining traits, no internal shell, no suckers, no eye pigment, debunking the claim. Octopuses likely arose in the Jurassic, leaving a deep gap in the fossil record.

This episode was generated by AI from the cited research paper.