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.
Latest about cretaceous period
If you thought T. rex had tiny arms, wait until you see this apex predator's ridiculously tiny appendages
Newly discovered dinosaur — the apex predator of its environment — had a weirdly flat skull compared to its contemporaries, along with ridiculously small arms.
Enormous dinosaur dubbed Shiva 'The Destroyer' is one of the biggest ever discovered
Researchers discovered the remains of a huge dinosaur named Bustingorrytitan shiva last year and have now released artistic reconstructions of the Cretaceous giant.
'Living fossil' tree frozen in time for 66 million years being planted in secret locations
Wollemi pines — thought to have gone extinct 2 million years ago — were rediscovered in 1994. Scientists are now hoping to reintroduce the species in the wild in a conservation effort that could take centuries.
'Cut down in their prime': Dinosaurs were thriving in Africa before the asteroid hit
The discovery of predatory dinosaurs in marine sediments in Morocco suggests life was abundant and diversifying at the end of the Cretaceous period.
Dinosaur-era frog found fossilized with belly full of eggs and was likely killed during mating
Gravid frog found in 100 million-year-old deposits in China is oldest fossil of its kind ever discovered.
Newfound T. rex relative was an even bigger apex predator, remarkable skull discovery suggests
The newly identified tyrannosaur species is the closest known relative of T. rex and could have been even larger than the famous dinosaur king.
120 million-year-old birds tracks near South Pole are the oldest ever discovered in the Southern Hemisphere
Fossilized bird tracks discovered in Australia show these ancient creatures lived in the southern polar regions on the supercontinent of Gondwana.
'Hell fish' likely killed by dinosaur-ending asteroid is preserved in stunning detail
Scientists recently unearthed stunning fossils of sturgeon from Hell's Creek that might have died on the day that the dinosaur-killing asteroid struck.
