"3D Fossil Reveals Evolutionary Clues to Vertebrate Skull Development"
A 455-million-year-old fossil of the jawless fish Eriptychius americanus has provided new insights into the evolution of vertebrate skulls. The fossil, discovered in Colorado, is the oldest 3D evidence of cranial anatomy in an early vertebrate. The skull arrangement of E. americanus is unlike anything seen in living vertebrates or its extinct relatives, with unfused cartilage sections surrounding the mouth, olfactory organs, and eyes. CT scans allowed researchers to visualize the cartilage and reconstruct a digital model of the fish's cranium. The fossil fills a gap in our understanding of vertebrate head evolution and provides valuable insights into the ancient jawless fish's anatomy.