Carbon isotope excursion[clarification needed] suggests that the Asian Teilhardina asiatica is the oldest member of the genus; the youngest is the North American Teilhardina brandti.[5] However finds in Wyoming suggest Teilhardina may have originated in North America.[6]
There are four hypotheses that have been proposed to try and explain the geographic distribution:[5]
Africa was the origination of the primates and then they dispersed to Europe- Greenland and finally North America.
Primates originated in North America then dispersed to Asia through the Bering route and later passed through Greenland to finally reach Europe.
Primates originated in Asia or Africa and dispersed through North America and finally reaching western Europe.
Asia was the primate’s origination, they then dispersed eastward towards North America and westward to Europe.
At one point a hypothesis arose that the primates may have originated in India prior to the plate collision with Asia near the Paleocene-Eocene boundary and they spread into Asia afterwards.[5]
These hypotheses were re-evaluated using new morphological evidence and earliest records of Teilhardina species from the continents concerned. The researchers concluded that none of the hypotheses fit the pattern that had emerged from their studies.[5] It is now believed that at the beginning of the Paleocene–Eocene Thermal MaximumTeilhardina dispersed from east to west. The earliest primates migrated across the Turgai Straits from South Asia to Europe, finally dispersing to North America through Greenland.[5]
Taxonomy
Although Teilhardina has been usually assigned to Omomyidae, it has also been recovered as polyphyletic, with T. belgica and T. asiatica nested as the basalmost haplorrhines, and others being recovered as anaptomorphineomomyids (and thus more closely related to the tarsiers than to simians).[7]T. crassidens has been referred to the genus Baataromomys,[8] but has also been assigned to the new genus Bownomomys along with T. americana.[9]
Species
Teilhardina magnoliana is the earliest known North Americanprimate; its fossil was first discovered in the US state of Mississippi. It was a tree-dwelling fur-covered tiny creature with a long, slender tail; the tail was significantly longer than the body.[1][10]
The discoverer, K. Christopher Beard of the Carnegie Museum of Natural History (Pittsburgh, Pennsylvania), posited that Teilhardina magnoliana's ancestors crossed the land bridge from Siberia to the Americas, possibly more than 55.8 million years ago, although the age of the discovered fossil is a matter of disagreement. The animal weighed approximately one ounce.[11]
^Tornow, M.A. (2008). "Systematic analysis of the Eocene primate family Omomyidae using gnathic and postcranial data". Bulletin of the Peabody Museum of Natural History. 49 (1): 43–129. doi:10.3374/0079-032X(2008)49[43:SAOTEP]2.0.CO;2. S2CID86262940.
^Morse, Paul E.; Chester, Stephen G.B.; et al. (March 2019). "New fossils, systematics, and biogeography of the oldest known crown primate Teilhardina from the earliest Eocene of Asia, Europe, and North America". Journal of Human Evolution. 128: 103–131. Bibcode:2019JHumE.128..103M. doi:10.1016/j.jhevol.2018.08.005. PMID30497682. S2CID54167483.
