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Taeniodont
Taeniodonta ("banded teeth") is an extinct order of eutherian mammals, that lived in North America and Europe from the late Cretaceous (Maastrichtian) to the middle Eocene. Taeniodonts evolved quickly into highly specialized digging animals, and varied greatly in size, from rat-sized to species as large as a bear. Later species developed prominent front teeth and huge claws for digging and rooting. Some genera, like ''Stylinodon'', had ever-growing teeth. The scarcity of taeniodont fossils can be explained by the fact that these animals probably lived in dry or arid climates unconductive to fossilization. According to 2022 studies of Bertrand, O. C. and Sarah L. Shelley, taeniodonts are identified to be a basal placental Placental mammals (infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupialia. Placentalia contains the vast majority of extant mammals, which are partly distinguished ... mammal. G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylinodon
''Stylinodon'' ("tooth with pilar-like fibers") is an extinct genus of taeniodonts from extinct tribe Stylinodontini within subfamily Stylinodontinae and family Stylinodontidae, that lived in North America from early to middle Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ....Schoch, Robert M. (1986."Systematics, functional morphology and macroevolution of the extinct mammalian order Taeniodonta."Bulletin of the Peabody Museum of Natural History, (42).S. G. Lucas, R. M. Schoch, and T. E. Williamson (1998."Taeniodonta".In C. M. Janis, K. M. Scott, and L. L. Jacobs (eds.)"Evolution of Tertiary Mammals of North America, Volume 1: Terrestrial Carnivores, Ungulates, and Ungulate like Mammals" Cambridge University Press, 703 pages With a weight between and , and length of , it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylinodontidae
Stylinodontidae ("teeth with pilar-like fibers") is an extinct family of mammals from extinct superfamily Stylinodontoidea within extinct order Taeniodonta, that lived in North America from the early Paleocene to middle Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes .... Taxonomy and phylogeny Taxonomy Phylogeny References Paleocene mammals Eocene mammals Prehistoric mammal families {{paleo-mammal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conoryctella
''Conoryctella'' ("cone digger of earth") is an extinct genus of taeniodonts from extinct tribe Conoryctellini within extinct subfamily Conoryctinae and extinct family Conoryctidae, that lived in North America during the early Paleocene The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), .... Phylogeny References Taeniodonta Prehistoric mammal genera {{paleo-mammal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schowalteria
''Schowalteria'' is a genus of extinct mammal from the Cretaceous of Canada. It is the earliest known representative of order Taeniodonta, a specialised lineage of eutherian mammals otherwise found in Paleocene and Eocene deposits. It is notable for its large size, being among the largest of Mesozoic mammals, as well as its speciation towards herbivory, which in some respects exceeds that of its later relatives. Description Currently, ''Schowalteria'' is considered to be a monotypic genus, with only one species, ''S. clemensi''. It is known from only one skull. ''Schowalteria'' shares some speciations with later taeniodonts, namely similar canine and incisor morphology, similar facial proportions and zygomatic arch construction, though unlike them its occlusal surface is worn nearly completely flat, and the wear facet completely encompasses the paracone and metacone, leaving only an outline of the buccal side of the bases of these cusps remaining, differing radically from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conoryctini
Conoryctinae ("cone diggers") is an extinct subfamily of taeniodonts from extinct family Conoryctidae, that lived in North America from the early to middle Paleocene The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), .... Taxonomy and phylogeny Taxonomy Phylogeny References Paleocene mammals Eocene mammals {{paleo-mammal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutheria
Eutheria (from Greek , 'good, right' and , 'beast'; ), also called Pan-Placentalia, is the clade consisting of Placentalia, placental mammals and all therian mammals that are more closely related to placentals than to marsupials. Eutherians are distinguished from non-eutherians by various phenotypic traits of the feet, ankles, jaws and teeth. All extant eutherians lack epipubic bones, which are present in all other living mammals (marsupials and monotremes). This allows for expansion of the abdomen during pregnancy, though epipubic bones are present in many primitive eutherians. Eutheria was named in 1872 by Theodore Gill; in 1880, Thomas Henry Huxley defined it to encompass a more broadly defined group than Placentalia. The earliest unambiguous eutherians are known from the Early Cretaceous Yixian Formation of China, dating around 120 million years ago. Two tribosphenic mammals, ''Durlstodon'' and ''Durlstotherium'' from the Berriasian age (~145–140 million years ago) of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conoryctidae
Conoryctidae ("cone diggers") is an extinct family of mammals from extinct order Taeniodonta, that lived in North America and Europe from the early Paleocene to early Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes .... Taxonomy and phylogeny Taxonomy Phylogeny References Paleocene mammals Eocene mammals Prehistoric mammal families {{paleo-mammal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placentalia
Placental mammals ( infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupialia. Placentalia contains the vast majority of extant mammals, which are partly distinguished from monotremes and marsupials in that the fetus is carried in the uterus of its mother to a relatively late stage of development. The name is something of a misnomer, considering that marsupials also nourish their fetuses via a placenta, though for a relatively briefer period, giving birth to less-developed young, which are then nurtured for a period inside the mother's pouch. Placentalia represents the only living group within Eutheria, which contains all mammals that are more closely related to placentals than they are to marsupials. Anatomical features Placental mammals are anatomically distinguished from other mammals by: * a sufficiently wide opening at the bottom of the pelvis to allow the birth of a large baby relative to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Aus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyly
Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic grouping (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of synapomorphies and symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term received currency during the debates of the 1960s and 1970s accompanying the rise of cladistics, having been coined by zoologist Willi Hennig to apply to well-known taxa like Reptilia (reptiles), which is paraphyletic with respect to birds. Reptilia contains the last common ancestor of reptiles and all descendants of that ancest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
