Euarchonta

Euarchontans Temporal range: Late Cretaceous - Recent
Euarchonts: upper left: Plesiadapis, upper right: Northern Treeshrew, lower left: Sunda Flying Lemur and lower right: Yellow Baboon
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Subclass:	Theriiformes
Infraclass:	Eutheria
(unranked):	subcohort Exafroplacentalia (Notolegia)
Magnorder:	Boreoeutheria
Superorder:	Euarchontoglires
(unranked):	Euarchonta
Orders
Scandentia   Primatomorpha   Dermoptera   Primates

The Euarchonta are a grandorder of mammals containing four orders: the Dermoptera or colugos, the Scandentia or treeshrews, the extinct Plesiadapiformes, and the Primates.

The term "Euarchonta" (meaning "true ancestors") first appeared in the general scientific literature in 1999, when molecular evidence suggested that the morphology-based Archonta be trimmed down to exclude Chiroptera. Major DNA sequence analyses of predominantly nuclear sequences (Murphy et al., 2001) support the Euarchonta hypothesis, while a major study investigating mitochondrial sequences supports a different tree topology (Arnason et al., 2002). A study investigating retrotransposon presence/absence data has claimed strong support for Euarchonta (Kriegs et al., 2007). Some interpretations of the molecular data link Primates and Dermoptera in a clade (mirorder) known as Primatomorpha, which is the sister of Scandentia. In some the Dermoptera are a member of the primates rather than a sister. Other interpretations link the Dermoptera and Scandentia together in a group called Sundatheria as the sister group of the primates. Together, the three are known as Euarchonta, the "True Founders".

Euarchonta and Glires together form the Euarchontoglires, one of the four Eutherian clades.

Euarchontoglires	Glires Rodentia (rodents) Lagomorpha (rabbits, hares, pikas) Euarchonta Scandentia (treeshrews) Primatomorpha Dermoptera (flying lemurs) Primates (†Plesiadapiformes, Strepsirrhini, Haplorrhini)

Note that as eu- becomes ev- before vowels in Latin, Euarchonta is not a proper Latin phonological construct—Evarchonta would be appropriate. This is applied inconsistently in English, for example in euergetism on one hand and evangelism on the other.

References

• Murphy W. J., E. Eizirik, W. E. Johnson, Y. P. Zhang, O. A. Ryder, S. J. O'Brien, 2001a. Molecular phylogenetics and the origins of placental mammals Nature 409:614-618. [1]

• Ulfur Arnason, et al. Mammalian mitogenomic relationships and the root of the eutherian tree. Proceedings of the National Academy of Science 99: 8151-8156. [2]

• Jan Ole Kriegs, Gennady Churakov, Jerzy Jurka, Jürgen Brosius, and Jürgen Schmitz (2007) Evolutionary history of 7SL RNA-derived SINEs in Supraprimates. Trends in Genetics 23 (4): 158-161 [3] (PDF version [4])

External links

• Nikolaev, S., Montoya-Burgos, J.I., Margulies, E.H., Rougemont, J., Nyffeler, B., Antonarakis, S.E. 2007. Early history of mammals is elucidated with the ENCODE multiple species sequencing data. PLoS Genet. 3:e2, doi:10.1371/journal.pgen.0030002.
• Gennady Churakov, Jan Ole Kriegs, Robert Baertsch, Anja Zemann, Jürgen Brosius, Jürgen Schmitz. 2008. Mosaic retroposon insertion patterns in placental mammals