Alagomyidae is a family of
rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...
s known from the late
Paleocene
The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pal ...
and early
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...
of
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...
and
North America (McKenna and Bell, 1997). Alagomyids have been identified as the most
basal rodents, lying outside the common ancestry of living forms (Meng et al., 1994). Because of their
phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
position and their conservative
dental morphology, alagomyids have played a key role in investigations of the origins and relationships of rodents (Meng et al., 1994; Meng and Wyss, 2001).
References
*McKenna, Malcolm C., and Bell, Susan K. 1997. ''Classification of Mammals Above the Species Level.'' Columbia University Press, New York, 631 pp.
*Meng, J., A.R. Wyss, M.R. Dawson, and R. Zhai, 1994. Primitive fossil rodent from Inner Mongolia and its implications for mammalian phylogeny ''Nature'' 370:134-136.
*Meng, J., and A.R. Wyss, 2001. The morphology of ''Tribosphenomys'' (Rodentiaformes, Mammalia): phylogenetic implications for basal Glires ''Journal of Mammalian Evolution'' 8(1):1-71.
Paleocene rodents
Eocene rodents
Paleocene first appearances
Eocene extinctions
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