The Cretaceous (, krih-TAY-shəs) is a geologic period and system that spans from the end of the Jurassic Period 145 million years ago (mya) to the beginning of the Paleogene Period 66 mya. It is the last period of the Mesozoic Era, and the longest period of the Phanerozoic Eon. The Cretaceous Period is usually abbreviated K, for its German translation Kreide (chalk, creta in Latin).
The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites and rudists, while dinosaurs continued to dominate on land. During this time, new groups of mammals and birds, as well as flowering plants, appeared.
Selected article on the Cretaceous world and its legacies
is a genus
of dromaeosaurid theropod dinosaur
that lived approximately 75 to 71 million years ago
during the Late Cretaceous Epoch
. Two species are currently recognized, although others have been assigned in the past. The type species
is V. mongoliensis
of this species have been discovered in Mongolia
. A second species, V. osmolskae
, was named in 2008 for skull material from Inner Mongolia
Like other dromaeosaurids like Deinonychus and Achillobator, Velociraptor was a bipedal, feathered carnivore with a long tail and an enlarged sickle-shaped claw on each hindfoot, which is thought to have been used to tackle prey. Velociraptor can be distinguished from other dromaeosaurids by its long and low skull, with an upturned snout.
Velociraptor (commonly shortened to "raptor") is one of the dinosaur genera most familiar to the general public due to its prominent role in the Jurassic Park motion picture series. In the films it was shown with anatomical inaccuracies, including being much larger than it was in reality and without feathers. Some of these inaccuracies, along with the head's larger dome in the movies may suggest that the dinosaurs in the movies were actually modeled on Deinonychus. Velociraptor is also well known to paleontologists, with over a dozen described fossil skeletons, the most of any dromaeosaurid. One particularly famous specimen preserves a Velociraptor locked in combat with a Protoceratops. (see more...)
Did you know?
- ... that over the course of the history of stegosaur research, their iconic back plates have been thought to function as armor plating, to regulate body temperature, or to attract mates?
- ... that major discoveries in the history of ceratosaur research include horned predators like Ceratosaurus (pictured), Majungasaurus, and Carnotaurus, as well as a bonebed of the projecting-toothed Masiakasaurus?
- ... that historical therizinosaur research misinterpreted these unusual bird-like herbivorous dinosaurs as giant turtles, semiaquatic fish-eaters, and tree-climbing insectivores?
- ... that T. Rex and the Crater of Doom details the development of the hypothesis that dinosaurs were wiped out by a meteor impact?
- ... that "color markings", considered rare among fossil crabs, have been found on Avitelmessus?
Do you have a question about Cretaceous that you can't find the answer to?
Consider asking it at the Wikipedia reference desk.
Selected article on the Cretaceous in human science, culture or economics
The geologic map of Georgia
(a state within the United States) is a special-purpose map
made to show geological
units or geologic strata
are shown by colors or symbols to indicate where they are exposed at the surface. Structural features such as faults
and shear zones
are also shown. Since the first national geological map, in 1809, there have been numerous maps which included the geology of Georgia. The first Georgia specific geologic map was created in 1825. The most recent state-produced geologic map of Georgia, by the Georgia Department of Natural Resources
is 1:500,000 scale, and was created in 1976 by the department's Georgia Geological Survey. It was generated from a base map produced by the United States Geological Survey
. The state geologist and Director of the Geological Survey of Georgia was Sam M. Pickering, Jr. Since 1976, several geological maps of Georgia, featuring the state's five distinct geologic regions, have been produced by the federal government. (see more...
Things you can do
Current Cretaceous FACs - none currently