Apart from the Biarmosuchia and the Eotitanosuchidae, the Dinocephalia are the least advanced among the therapsids, although still uniquely specialised in their own way. They retain a number of primitive characteristics (e.g. no secondary palate, small dentary) shared with their pelycosaur ancestors, although they are also more advanced in possessing therapsid adaptations like the expansion of the ilium and more erect limbs. They include carnivorous, herbivorous, and omnivorous forms, some semi-aquatic and some fully terrestrial, and were also among the largest animals of the Permian period; only the biggest Caseidae and Pareiasauridea rivalling or even exceeding them in size.
All dinocephalians are distinguished by having interlocking incisors allowing a shearing contact between upper and lower teeth. In more advanced forms, the heels on the lingual sides of the incisor teeth met to form a crushing surface when the jaws were shut, allowing the grinding up of plant matter.
Most dinocephalians also developed pachyostosis of the bones in the skull, which seems to have been an adaptation for intra-specific behaviour (head-butting), perhaps for territory or a mate. In some types, such as Estemmenosuchus and Styracocephalus there are also horn-like structures, which evolved independently in each case.
Dinocephalians are extraordinary for their large size. The biggest herbivores (Tapinocephalus) and omnivores (Titanosuchus), may have massed up to two tonnes in weight, and were some 4.5 meters long, while the largest carnivores (such as Titanophoneus and Anteosaurus) were at least as long, with heavy skulls 80 cm long, and overall weights of around half a tonne.
Read more about this topic: Dinocephalia
Other articles related to "description":
... Unlike the keywords attribute, the description attribute is supported by most major search engines, like Yahoo! and Bing, while Google will fall back on this tag when information about the ... The description attribute provides a concise explanation of a Web page's content ... the Web page authors to give a more meaningful description for listings than might be displayed if the search engine was unable to automatically create its own ...
... audience, creating a dominant impression, using descriptive language, and organizing the description are the rhetorical choices to be considered when using a description ... A description is usually arranged spatially but can also be chronological or emphatic ... The focus of a description is the scene ...
... Universal Description, Discovery and Integration (UDDI, pronounced Yu-diː) is a platform-independent, Extensible Markup Language (XML)-based registry by which businesses ... designed to be interrogated by SOAP messages and to provide access to Web Services Description Language (WSDL) documents describing the protocol bindings and message formats required to ...
... He gives a vivid and accurate description of the last colony of the European Beaver in Wales on the River Teifi, but spoils it by repeating the legend that beavers castrate themselves ... Likewise he gives a good description of an Osprey fishing, but adds the mythical detail that the bird has one webbed foot ... His description of Irish wildlife was harshly called "worthless" the better view perhaps is that despite its faults it gives a valuable glimpse of Irish fauna in the 1180s ...
Famous quotes containing the word description:
“It [Egypt] has more wonders in it than any other country in the world and provides more works that defy description than any other place.”
—Herodotus (c. 484424 B.C.)
“The next Augustan age will dawn on the other side of the Atlantic. There will, perhaps, be a Thucydides at Boston, a Xenophon at New York, and, in time, a Virgil at Mexico, and a Newton at Peru. At last, some curious traveller from Lima will visit England and give a description of the ruins of St Pauls, like the editions of Balbec and Palmyra.”
—Horace Walpole (17171797)
“God damnit, why must all those journalists be such sticklers for detail? Why, theyd hold you to an accurate description of the first time you ever made love, expecting you to remember the color of the room and the shape of the windows.”
—Lyndon Baines Johnson (19081973)