The Cretaceous period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic period, about 146 million years ago (Ma), to the beginning of the Paleocene epoch of the Tertiary period (65.5 Ma). The end of the Cretaceous also defines the boundary between the Mesozoic and Cenozoic eras. Cretaceous - Name and dating. As with other older geologic periods, the rock beds that define the Cretaceous are well identified, but the exact dates of the pe ...

Including:

• Cretaceous - Name and dating
• Cretaceous - Divisions
• Cretaceous - Paleogeography
• Cretaceous - Flora
• Cretaceous - Fauna
• Cretaceous - Land animals
• Cretaceous - Marine animals
• Cretaceous - Extinction
• Cretaceous - References and further reading

Read more here: » Cretaceous: Encyclopedia - Cretaceous

Cretaceous - Land animals. On land, mammals were a small and still relatively minor component of the fauna. The fauna was dominated by archosaurian reptiles, especially dinosaurs, which were at their most diverse. Pterosaurs were common in the early and middle Cretaceous, but as the Cretaceous proceeded faced growing competition from the adaptive radiation of birds, and by the end of the period only two h ...

See also:

Cretaceous, Cretaceous - Name and dating, Cretaceous - Divisions, Cretaceous - Paleogeography, Cretaceous - Flora, Cretaceous - Fauna, Cretaceous - Land animals, Cretaceous - Marine animals, Cretaceous - Extinction, Cretaceous - References and further reading

Read more here: » Cretaceous: Encyclopedia II - Cretaceous - Fauna

During the Cretaceous, the late Paleozoic - early Mesozoic supercontinent of Pangea completed its breakup into present day continents, although their positions were substantially different at the time. As the Atlantic Ocean widened and South America drifted westwards, Gondwana itself broke up as Antarctica and Australia rifted away from Africa (though India and Madagascar remained attached). Such active rifting lifted great undersea mountain chains along the welts, raising eustatic sea levels worldwide. To the north of Africa the Tethys Sea ...

See also:

Cretaceous, Cretaceous - Name and dating, Cretaceous - Divisions, Cretaceous - Paleogeography, Cretaceous - Flora, Cretaceous - Fauna, Cretaceous - Land animals, Cretaceous - Marine animals, Cretaceous - Extinction, Cretaceous - References and further reading

Read more here: » Cretaceous: Encyclopedia II - Cretaceous - Paleogeography