500-Million-Year-Old 'Smiling' Worm Rears Its Head
Wednesday, June 24, 2015 - 12:30
in Paleontology & Archaeology
Scientists have finally seen the face of the ancient worm Hallucigenia, which leaves fossils so bizarre researchers once thought its top was its bottom and its back was its front. And it's a doozy, with a circular tooth-lined mouth and throat.