Ovarian follicles shed new light on dinosaur reproduction during the transition towards birds

The reproductive systems of living archosaurs, crocodilians and birds are very different; the derived features present in birds are inferred to have evolved within the derived archosaur group, Dinosauria, which includes Aves (the common ancestor of Archaeopteryx + living birds) as a member of the derived theropod clade, Maniraptora. Compared to Aves, crocodilians have two ovaries, prolonged folliculogenesis (maturation of ovarian follicles),...