Cenozoic: Encyclopedia - Cenozoic

Cenozoic

The Cenozoic Era (sen-oh-ZOH-ik; sometimes Caenozoic Era in the United Kingdom) meaning "new life" (Greek kaino = new + zoikos = life) is the most recent of the four classic geological eras. It covers the 65.5 million years since the Cretaceous-Tertiary extinction event at the end of the Cretaceous that marked the demise of the last dinosaurs and the end of the Mesozoic Era. The Cenozoic era is ongoing.

The Cenozoic is divided into two periods, the Palaeogene and Neogene, and they are in turn divided into epochs. The Palaeogene consists of the Paleocene, Eocene, and Oligocene epochs, and the Neogene consists of the Miocene, Pliocene, Pleistocene, and Holocene epochs, the last of which is ongoing. Previously the Cenozoic was divided into periods (or sub-eras) named the Tertiary (Paleocene to Pliocene) and Quaternary (Pleistocene and Holocene). However, they are no longer recognized. Cenozoic gets its name from the Greek words ceno (new) and zoo (animals).

The Cenozoic is the age of mammals. During the Cenozoic, mammals diverged from a few small, simple, generalized forms into a diverse collection of terrestrial, marine, and flying animals. The Cenozoic is just as much the age of savannas, or the age of co-dependent Angiosperms (flowering plants) and insects. Birds also evolved substantially in the Cenozoic.

Geologically, the Cenozoic is the era when continents moved into their current positions. Australia-New Guinea split from Gondwana to drift north and, eventually, abut South-east Asia; Antarctica moved into its current position over the South Pole; the Atlantic Ocean widened and, late in the era, South America became attached to North America.

See also

• Geologic Time Scale

Cenozoic - References and further reading

• British Caenozoic Fossils, 1975, The Natural History Museum, London.

Category: Cenozoic

Adapted from the Wikipedia article "Cenozoic", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki