Laurasiatheria

Cladus: Eukaryota
Supergroup: Opisthokonta
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclassis: Tetrapoda
Classis: Mammalia
Subclassis: Theria
Infraclassis: Eutheria
Superordo: Laurasiatheria
Ordines: Artiodactyla - Carnivora - Cetacea - Chiroptera - †Cimolesta - †Condylarthra - †Creodonta - Insectivora - †Mesonychia - Perissodactyla - Pholidota

Name

Laurasiatheria Gill, 1872

Vernacular names
Internationalization
English: Laurasiatheres
日本語: ローラシア獣上目
Русский: Лавразиотерии
Українська: Лавразіотерії
中文: 勞亞獸總目

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Laurasiatheria is a large group of placental mammals. It includes bats, whales, most hoofed mammals, and carnivorans, among other mammals.
Classification and phylogeny

Laurasiatheria was discovered on the basis of the similar gene sequences shared by the mammals belonging to it. No anatomical features have yet been found that unite the group. Laurasiatheria is a clade usually discussed without a Linnaean rank, but has been assigned the rank of cohort or magnorder, and superorder. The Laurasiatheria clade is based on DNA sequence analyses and retrotransposon presence/absence data. The name comes from the theory that these mammals evolved on the supercontinent of Laurasia, after it split from Gondwana when Pangaea broke up. It is a sister group to Euarchontoglires (Supraprimates) and Afrotheria. It includes the following extant orders:

* Erinaceomorpha: hedgehogs and gymnures
* Soricomorpha: moles, shrews, solenodons (cosmopolitan)
* Cetacea: whales, dolphins and porpoises (cosmopolitan)
* Artiodactyla: even-toed ungulates, including pigs, hippopotamuses, camels, giraffes, deer, antelopes, cattle, sheep, goats (cosmopolitan)
* Pegasoferae:
o Pholidota: pangolins or scaly anteaters (Africa, South Asia)
o Chiroptera: bats (cosmopolitan)
o Carnivora: carnivores (cosmopolitan)
o Perissodactyla: odd-toed ungulates

Within the Laurasiatheria, the Erinaceomorpha appears to be the most divergent branch. Some studies link the Perissodactyla and Ferae in a clade Zooamata; others link Perissodactyla and Cetartiodactyla in a clade of true ungulates[citation needed]. Neither clade is well supported.

Laurasiatheria is also posited to include several extinct orders and superorders:

* Meridiungulata
* Condylarthra
* Dinocerata
* Mesonychia
* Cimolesta
* Creodonta
References

1. ^ Waddell, Peter J., Okada, Norihiro, & Hasegawa, Masami (1999). "Towards resolving the interordinal relationships of placental mammals". Systematic Biology 48 (1): 1–5. doi:10.1093/sysbio/48.1.1. http://www.deer.rr.ualberta.ca/library/taxonomy/reading.pdf. Retrieved 2009-10-26.


* William J. Murphy, Eduardo Eizirik, Mark S. Springer et al., Resolution of the Early Placental Mammal Radiation Using Bayesian Phylogenetics,Science, Vol 294, Issue 5550, 2348-2351, 14 December 2001.
* Jan Ole Kriegs, Gennady Churakov, Martin Kiefmann, Ursula Jordan, Juergen Brosius, Juergen Schmitz. (2006) Retroposed Elements as Archives for the Evolutionary History of Placental Mammals. PLoS Biol 4(4): e91.[1] (pdf version)
* Kitazoe Y, Kishino H, Waddell PJ, Nakajima N, Okabayashi T, et al. (2007) "Robust Time Estimation Reconciles Views of the Antiquity of Placental Mammals." PLoS ONE 2(4): e384. doi:10.1371/journal.pone.0000384

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