View your list of saved words. (You can log in using Facebook.)
Interval of geologic time from c. 145.5 to 65.5 million years ago. During the Cretaceous the climate was warmer than today. In the seas, marine invertebrates flourished, and bony fishes evolved. On land, flowering plants arose, and insects, bees in particular, began their thriving partnership with them. Mammals and birds remained inconspicuous throughout the Cretaceous, while the reptiles continued their dominance. The dinosaurs reached the peak of their evolution during this period but rather suddenly became extinct at its end.
This entry comes from Encyclopædia Britannica Concise. For the full entry on Cretaceous Period, visit Britannica.com.
Seen & Heard
What made you look up Cretaceous Period? Please tell us what you were reading, watching or discussing that led you here.