Scientists have discovered that a 300-million-year-old fossil (trace of an ancient creature preserved in stone), thought to be the world’s earliest known octopus, isn’t one after all. They now think it’s a nautiloid, an ancient relative of the nautilus, a tentacled sea creature with a shell.
The fossil, called Pohlsepia mazonensis, was found in Illinois, US, and identified as an octopus 26 years ago. Octopus fossils are rare because their bodies are made of soft muscle and skin, which break down quickly after they die, leaving almost nothing to preserve in rock.
Scientists at the University of Reading, England, recently studied the fossil again using a technique that shines beams brighter than the Sun into rock. This revealed new details, like tiny teeth, that matched another nautiloid fossil found nearby.…