Tiny Permian Reptile Sheds Light on the Dawn of Rib-Driven Breathing
Researchers studying a 289-million-year-old Captorhinus aguti fossil from Oklahoma, using neutron tomography, preserved skin, cartilage and protein remnants to reconstruct a rib-based (costal) breathing system—the ancestral mechanism for drawing air into lungs in amniotes—explaining how early land-dwellers became more active; the find also yields the oldest preserved proteins, pushing soft-tissue preservation back about 100 million years, with the fossils housed at the Royal Ontario Museum.
