The Cretaceous, the last and longest period of the dinosaur age, lasted from about 145.5 million to about 65.5 million years ago. During the Cretaceous, mammals were small, about rat size, and the land was ruled by dinosaurs, including the duck-bills (hadrosaurs), horned dinosaurs (Triceratops), long-neck sauropods (Dreadnoughtus) and the tyrannosaurs (Tyrannosaurus rex). When the 79-million-year-long period ended, largely because of a 6-mile-wide (10 kilometers) asteroid slamming into the Yucatan Peninsula, about 80 percent of all animal species went extinct, including the non-avian dinosaurs.
The discovery of predatory dinosaurs in marine sediments in Morocco suggests life was abundant and diversifying at the end of the Cretaceous period.
Gravid frog found in 100 million-year-old deposits in China is oldest fossil of its kind ever discovered.
The newly identified tyrannosaur species is the closest known relative of T. rex and could have been even larger than the famous dinosaur king.
Fossilized bird tracks discovered in Australia show these ancient creatures lived in the southern polar regions on the supercontinent of Gondwana.
Scientists recently unearthed stunning fossils of sturgeon from Hell's Creek that might have died on the day that the dinosaur-killing asteroid struck.
New analysis of the ancient crocodylian Deinosuchus confirms that this apex predator had jaws and teeth that were powerful enough to subdue massive dinosaur prey.
'Prehistoric Planet,' a five-part documentary series, transports viewers into the mesmerizing world of the Cretaceous period.
The Cretaceous period lasted approximately 79 million years, and ended with a major extinction event about 66 million years ago.
Scientists recently discovered fossils in Argentina that belong to Thanatosdrakon. The specimens are the largest pterosaurs ever found in South America.
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