The Cretaceous period is known because the Earth's land was assembled into two continents (Laurasia and Gondwana), when a Archeologist discover a fossil dated back to this period it is most likely that it comes from Big Bend National Park (Texas), since it is where rocks from late Cretaceous are found, as well in the southern Canada, Montana, and nearby areas. The climate in the Cretaceous was hot and dry, wgich most of the land covered by deserts and forests.