Scientists finally resolved a long-standing debate over the classification of a 300-million-year-old fossil, which was once thought to be an octopus. This discovery, known as Pohlsepia mazonensis, was reclassified as a nautilus relative after advanced imaging techniques revealed critical details that challenged previous assumptions about cephalopod evolution. The fossil, originally described in 2000 as a cirrate octopus, was later reinterpreted through synchrotron micro-X-ray fluorescence imaging, which allowed researchers to identify previously undetected radula-like structures. These teeth, found exclusively in mollusks, provided evidence suggesting the fossil was not an octopus at all, but rather a nautilus species. The study, published in Proceedings of the Royal Society B, revealed that the missing elements were likely preservation artifacts, making a full count of 13 teeth the most plausible explanation. This reclassification overturned earlier molecular clock assumptions, revealing a more accurate timeline for the divergence of crown octopuses during the Jurassic period. The fossil also set a record for the oldest soft tissue preservation in the fossil record, surpassing previous records by approximately 220 million years. Dr. Thomas Clements emphasized that such discoveries often reveal hidden clues that lead to exciting new insights, underscoring the importance of advanced imaging in paleontology.
