Archivo: Bos sp. (cow) mandible 2 (47606347582)

Descripción: Bos sp. - cow mandible. (Ohio State University Museum of Zoology) Mammals are the dominant group of terrestrial vertebrates on Earth today. The group is defined based on a combination of features: endothermic (= warm-blooded), air-breathing, body hair, mother's milk, four-chambered heart, large brain-to-body mass ratio, two teeth generations, differentiated dentition, and a single lower jawbone. Almost all modern mammals have live birth - exceptions are the duck-billed platypus and the echidna, both of which lay eggs. Mammals first appear in the Triassic fossil record - they evolved from the therapsids (mammal-like reptiles). Mammals were mostly small and a minor component of terrestrial ecosystems during the Mesozoic. After the Cretaceous-Tertiary mass extinction at 65 million years ago, the mammals underwent a significant adaptive radiation - most modern mammal groups first appeared during this radiation in the early Cenozoic (Paleocene and Eocene). Three groups of mammals exist in the Holocene - placentals, marsupials, and monotremes. Other groups, now extinct, were present during the Mesozoic. Cows are domesticated bovines that have been widely bred. They occur on all continents except Antarctica. Classification: Animalia, Chordata, Vertebrata, Mammalia, Ungulata, Artiodactyla, Bovidae See info. at: <a href="https://en.wikipedia.org/wiki/Bos" rel="noreferrer nofollow">en.wikipedia.org/wiki/Bos</a> and <a href="https://en.wikipedia.org/wiki/Cattle" rel="noreferrer nofollow">en.wikipedia.org/wiki/Cattle</a>
Título: Bos sp. (cow) mandible 2 (47606347582)
Créditos: Bos sp. (cow) mandible 2
Autor(a): James St. John
Términos de Uso: Creative Commons Attribution 2.0
Licencia: CC BY 2.0
Enlace de Licencia: https://creativecommons.org/licenses/by/2.0
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