Leathery Eggs: New Fossil Discovery Sheds Light on Early Dinosaurs

A recent fossil discovery in China suggests that the first dinosaur egg was leathery, and the transition in egg morphology occurred early in the evolution of theropod dinosaurs. The discovery includes specimens of a new early Jurassic sauropodomorph dinosaur species, Qianlong shouhu, which comprises adult skeletons and five egg clutches. The embryos show some differences from the adults, indicating that Qianlong practiced colonial nesting. The study also found that relative egg size and eggshell thickness increased early in theropod evolution. Overall, the findings shed light on dinosaur reproductive biology and suggest that the first dinosaur egg was likely leathery, small, and elliptical.