Ancient Triassic sea reptile reveals oldest known gut anatomy
Researchers describe a 245-million-year-old marine reptile fossil from China, Austronaga minuta, with well-preserved stomach, liver and intestines. The find shows a simple single-chamber stomach and the organization of the gut, representing the oldest well-preserved digestive tract in a reptile and shedding light on how archosaur digestion evolved ahead of birds and crocodilians.