The black market trade in fossils stolen from the richest cretaceous fossil locality in the world has prompted a crackdown.
cretaceous , that period of the Mesozoic era that gave rise to the primitive mammals.
Placentalia must have come into existence during the cretaceous epoch.
During the chalk period, or "cretaceous epoch," not one of the present great physical features of the globe was in existence.
Species much like Rhinobatus occur in the cretaceous and Eocene.
There are some very remarkable instances of this in the cretaceous deposits.
The cretaceous ocean of the West was no less remarkable for its fishes than for its reptiles.
In the gorge of Cotahuasi, over seven thousand feet deep, about two thousand feet of cretaceous limestones are exposed.
Both were made at about the beginning of the upper cretaceous age.
The Mesozoic time certainly terminated with the cretaceous, and what follows belongs to a distinct aeon.
1670s, "chalky," from Latin cretaceus "chalk-like," from creta "chalk." As a geological period (with a capital C-), it was first used 1832. The extensive chalk beds of southeastern England were laid down during the Cretaceous.
The third and last period of the Mesozoic Era, from about 144 to 65 million years ago. During this time the supercontinent Pangaea continued to split up, with modern-day South America and Africa splitting apart, the Atlantic Ocean widening, and India disconnecting itself entirely from the other landmasses to which it was attached. Dinosaurs continued to be the dominant terrestrial animals, but many insect groups, modern mammals and birds, and the angiosperms (flowering plants) also first appeared. The Cretaceous Period ended with a mass extinction event in which about 75 percent of all species, including marine, freshwater, and terrestrial organisms, became extinct. See Chart at geologic time.