From the Triassic to the Early Jurassic, before the break-up of Pangaea, archosaurs (crocodiles and dinosaurs including birds) had a global distribution. This cosmopolitanism ended as Gondwana fragmented and Laurasia was assembled. Pterosaur diversity reach a maximum in the Late Jurassic—Early Cretaceous and plate tectonic didn't affect the distribution of these flying reptiles. Crocodiles also diversified during the Early Cretaceous but were divided into Laurasian and Gondwanan populations; modern crocodiles evolved from the former. The distribution of the three major groups of dinosaurs – the theropods, sauropods, and ornithischians – was similar that of the crocodiles. East Asia remained isolated with endemic species including psittacosaurs (horned dinosaurs) and Ankylosauridae (club-tailed, armoured dinosaurs).