Teilhardina Explained

Teilhardina ^[1] was an early marmoset-like primate that lived in Europe, North America and Asia during the Early Eocene epoch, about 56-47 million years ago.^{[2] [3]} The paleontologist George Gaylord Simpson is credited with naming it after the French paleontologist, Jesuit and philosopher Teilhard de Chardin.

Paleobiology

Carbon isotope excursion suggests that the Asian Teilhardina asiatica is the oldest member of the genus; the youngest is the North American Teilhardina brandti.^[4] However finds in Wyoming suggest Teilhardina may have originated in North America.^[5]

There are four hypotheses that have been proposed to try and explain the geographic distribution:

1. Africa was the origination of the primates and then they dispersed to Europe- Greenland and finally North America.
2. Primates originated in North America then dispersed to Asia through the Bering route and later passed through Greenland to finally reach Europe.
3. Primates originated in Asia or Africa and dispersed through North America and finally reaching western Europe.
4. 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.

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. It is now believed that at the beginning of the Paleocene–Eocene Thermal Maximum Teilhardina 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.

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 anaptomorphine omomyids (and thus more closely related to the tarsiers than to simians).^[6] T. crassidens has been referred to the genus Baataromomys,^[7] but has also been assigned to the new genus Bownomomys along with T. americana.^[8]

Species

Teilhardina magnoliana is the earliest known North American primate; 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.^{[2] [9]}

The discoverer, K. Christopher Beard of the Carnegie Museum of Natural History (Pittsburgh, Pennsylvania), posited that Teilhardina magnoliana 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.^[10]

External links

• Nat. Geo., Oldest Primate Fossil in North America Discovered. 3 March 2008; retrieved 22 August 2008

Notes and References

1. Web site: Heritage Daily. Oldest-known ancestor of modern primates may have come from North America, not Asia. 30 November 2018.
2. Beard, K.C. . 2008 . The oldest North American primate and mammalian biogeography during the Paleocene-Eocene Thermal Maximum . Proceedings of the National Academy of Sciences . 105 . 10 . 3815–8 . 10.1073/pnas.0710180105 . 18316721 . 2268774 . 2008PNAS..105.3815B . free .
3. Smith, T. . Rose, K.D. . Gingerich, P.D. . 2006 . Rapid Asia-Europe-North America geographic dispersal of earliest Eocene primate Teilhardina during the Paleocene-Eocene Thermal Maximum . Proceedings of the National Academy of Sciences . 103 . 30 . 11223–7 . 10.1073/pnas.0511296103 . 16847264 . 1544069. 2006PNAS..10311223S . free .
4. Smith. Thierry. Rose. Kenneth D.. Gingerich. Philip D.. 2006-07-25. Rapid Asia–Europe–North America geographic dispersal of earliest Eocene primate Teilhardina during the Paleocene–Eocene Thermal Maximum. Proceedings of the National Academy of Sciences of the United States of America. 103. 30. 11223–11227. 10.1073/pnas.0511296103. 0027-8424. 1544069. 16847264. 2006PNAS..10311223S. free.
5. Web site: Oldest-known ancestor of modern primates may have come from North America, not Asia . 29 November 2018 .
6. Ni . Xijun . Wang . Yuanqing . etal . January 2004 . A euprimate skull from the early Eocene of China . Nature . 427 . 1 . 65–68. 10.1038/nature02126. 14702085 . 2004Natur.427...65N . 4311702 .
7. Ni . Xijun . Beard . K. Christopher . etal . May 2007 . Discovery of the first early Cenozoic euprimate (Mammalia) from Inner Mongolia . American Museum Novitates . 3571 . 1–11 . 10.1206/0003-0082(2007)528[1:DOTFEC]2.0.CO;2. 55604250 .
8. Morse . Paul E. . Chester . Stephen G.B. . etal . 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 . 10.1016/j.jhevol.2018.08.005. 30497682 . 2019JHumE.128..103M . 54167483 .
9. A Monkey's Uncle, Smithsonian, May 2008, p. 16
10. Nickerson, C. 2008. A long trek for ancient mini monkeys. The Boston Globe