The Cretaceous Portal

Introduction

The Cretaceous ( /krəˈtʃəs/ krə-TAY-shəs) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin creta, "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation Kreide.

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. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the end of the Cretaceous, coincident with the decline and extinction of previously widespread gymnosperm groups. (Full article...)

Selected article on the Cretaceous world and its legacies

Dromaeosauroides is a genus of dromaeosaurid theropod dinosaur from the Early Cretaceous of what is now Denmark. It is known from two teeth, the first of which was found in 2000. Based on the first tooth, the genus and species Dromaeosauroides bornholmensis was named in 2003. The genus name means "Dromaeosaurus-like", due to the similarity to the teeth of that genus, and the species name means "from Bornholm". The holotype tooth is 21.7 millimetres (0.85 in) long, and the second tooth is 15 millimetres (0.59 in). They are curved and finely serrated. In life, Dromaeosauroides would have been 3 to 4 metres (10 to 10 ft) in length, and weighed about 40 kilograms (88 lb). As a dromaeosaur it would have been feathered, and had a large sickle claw on its feet like its relatives Dromaeosaurus and Deinonychus. Some teeth from Britain that have been referred to the genus Nuthetes may also belong to Dromaeosauroides. Coprolites containing fish remains found in the Jydegaard Formation may belong to this animal.

Dromaeosauroides was discovered in the Jydegaard Formation in Robbedale, on the island of Bornholm in the Baltic Sea. It is one of the oldest known dromaeosaurs in the world, and the first known uncontested dromaeosaur from the Early Cretaceous of Europe. It lived in a coastal lagoon environment with sauropods, as evidenced by a possible titanosaur tooth. Remains and tracks of other dinosaurs have been found in several formations on Bornholm. (see more...)

Did you know?

Need help?

Do you have a question about Cretaceous that you can't find the answer to?

Consider asking it at the Wikipedia reference desk.

Selected image



The painting Laelaps by Charles R. Knight depicts two Dryptosaurus fighting.
Photo credit: User:Crotalus horridus

Selected article on the Cretaceous in human science, culture or economics

Jurassic Park III is a 2001 American science fiction adventure monster film. It is the third installment in the Jurassic Park franchise and a sequel to the 1997 film The Lost World: Jurassic Park. It is the series' first film that was not directed by Steven Spielberg nor based on a book by Michael Crichton (though numerous scenes in the film were ultimately taken from Crichton's novels Jurassic Park and The Lost World). The film takes place on Isla Sorna, off Central America's Pacific coast, the island featured in the second film, where a divorced couple has tricked Dr. Alan Grant into going in order to help them find their son.

After the success of Spielberg's Jurassic Park, Joe Johnston expressed interest in directing a sequel, a film adaptation of The Lost World. Spielberg instead gave Johnston permission to direct the third film in the series, if there were to be one. Production of Jurassic Park III began on August 30, 2000. Upon its release, the film received mixed reviews, with many praising the visual effects and action scenes but finding the plot clichéd and unoriginal. Despite being less well-received than the previous films, Jurassic Park III was a box office success, grossing $368 million worldwide. (see more...)

Geochronology

Epochs - Early Cretaceous - Late Cretaceous
Stages - Berriasian - Valanginian - Hauterivian - Barremian - Aptian - Albian - Cenomanian - Turonian - Coniacian - Santonian - Campanian - Maastrichtian
Events - Cambrian–Ordovician extinction event - Great Ordovician Biodiversification Event - Taconic orogeny - Late Ordovician glaciation - Alice Springs Orogeny - Ordovician–Silurian extinction event

Landmasses - Baltica - Gondwana - Laurentia - Siberia
Bodies of water - Iapetus Ocean - Khanty Ocean - Proto-Tethys Ocean - Rheic Ocean - Tornquist Sea - Ural Ocean
Animals - Articulate brachiopods - Bryozoans - Cornulitids - Crinoids - Cystoids - Gastropods - Graptolites - Jawed fishes - Nautiloids - Ostracoderms - Rugose corals - Star fishes - Tabulate corals - Tentaculitids - Trilobites
Trace fossils - Petroxestes - Trypanites
Plants - Marchantiophyta

Fossil sites - Beecher's Trilobite Bed - Walcott–Rust quarry
Stratigraphic units - Chazy Formation - Fezouata formation - Holston Formation - Kope Formation - Potsdam Sandstone - St. Peter Sandstone

Researchers - Charles Emerson Beecher - Charles Lapworth - Charles Doolittle Walcott
Culture - Animal Armageddon - List of creatures in the Walking with... series - Sea Monsters

Quality Content

Things you can do


Here are some tasks awaiting attention:

Current Cretaceous FACs - none currently

Associated Wikimedia

The following Wikimedia Foundation sister projects provide more on this subject:

Wikibooks
Books

Commons
Media

Wikinews 
News

Wikiquote 
Quotations

Wikisource 
Texts

Wikiversity
Learning resources

Wiktionary 
Definitions

Wikidata 
Database