A Canadian PhD student helped uncover a 450-million-year-old jellyfish relative

Greta Ramirez-Guerrero was studying fragments of ancient life that had survived in Quebec rock for roughly 450 million years when she encountered an unusual problem: the animal she was examining had almost nothing that should have fossilised well. Paleocanna tentaculum was a soft-bodied relative of modern jellyfish, shaped more like a narrow tube than the drifting creatures familiar from today's seas. Yet dozens of its delicate remains had endured in limestone from the Ordovician period. Ramirez-Guerrero, a PhD candidate at the Université de Montréal, led the study that pieced together what the fossils represented.Across 15 slabs, the team identified around 135 specimens, giving her an unusually large collection of evidence for an animal of this kind. Their arrangement in the rock also offered clues about how quickly the creatures were buried and how their soft bodies managed to leave a trace behind.Greta Ramirez-Guerrero identified a 450-million-year-old jellyfish relativeThe fossils did not resemble the image most people have of a jellyfish. Paleocanna tentaculum was a polyp, with an elongated body enclosed within a narrow tube. At one end was a ring of tentacles.That distinction...