ABSTRACT
Understanding diversity can be undertaken by using inference from living forms, but the diversity of today offers just a small window on the historic succession of organisms. Paleontological expeditions accumulated more and more fossil discoveries, permitting the documentation not only of lineages but also of fossil assemblages in various places in Southeast Asia. The paleogeographic and tectonic history of Southeast Asia is extremely complex, comprising several continental and tectonic subunits, each of which has its own unique and complex history. Before the emergence of land life, terranes that would eventually constitute Southeast Asia and China were mostly distributed on the northern margin of Gondwanaland, also made up of India, Australia, Antarctica, Africa and South America. Mesozoic continental assemblages consisting of mollusks, vertebrates, and floras are particularly well documented in Thailand from the Late Triassic to the end of the Lower Cretaceous.
