March 4, 2008

Earliest Known North American Primate Discovered

A scientist from the Carnegie Museum of Natural History has discovered remains of the earliest-known primate to live in North America. The discovery also provides an explanation of how these long-extinct primates were able to reach the continent.

The primate, called Teilhardina magnoliana and part of the mammalian group that includes monkeys and apes, survived on berries and insects, and measured just three inches long weighing less than one ounce.

After unearthing the primate, paleontologist Christopher Beard of the Carnegie Museum of Natural History in Pittsburgh examined its teeth and dated the animal to 55.8 million years ago.  Beard said the species likely trekked across a now-vanished land bridge connecting Siberia to Alaska.

"For his time, he would have been about the smartest animal around. But that doesn't mean he was thinking deep thoughts," Beard told Reuters in a telephone interview.

"Primates have nails on their digits instead of claws. Primates have eyes that face forward and give us stereoscopic vision, instead of having eyes on the side of our heads like a dog or a horse. Primates almost always have relatively larger brains than other mammals," Beard said.

Beard said the Teilhardina was probably most concerned about its next meal of bugs, berries and fruit and staying away from lizards or birds of prey, along with one other basic instinct -- "Where are the girls?"

"It's a small, primitive primate. In some ways, it would have looked more like a teeny, tiny monkey than it would have looked like a small lemur," Beard said, explaining that the primate lived more than 10 million years before the first primitive monkeys.

He said although it was not ancestral to present day monkeys, it might have been in the lineage leading to a type of primitive primate known as Tarsiers that still lives in Southeast Asia.

Fossils of closely related species of Teilhardina have been found in China, Belgium, France and Wyoming.   Beard said the new species predates the one from Wyoming, and came from a time period when a land bridge connecting Asia to North America was the likely path the animals took to reach the continent.

How the earliest primates first entered North America has been the subject of much scientific debate, with some experts believing they crossed from Siberia and others believing they came from Europe via Greenland at a time when the continents were aligned differently than today.

The Teilhardina's fossil teeth were dug up near Meridian, Mississippi, close to the former coastline of the Gulf of Mexico.  They pre-date any primate fossils from Europe, said Beard, suggesting that rather than migrating from Europe to North America, this primate might have entered another way.

The Teilhardina lived 10 million years after a giant space rock wiped out the dinosaurs and other species, and mammals were beginning to exert their dominance on land.

The Bering land bridge was the route of many migrations over the ages, including dinosaurs.  Many experts believe the first modern humans entered North America through the same course between 12,000 to 30,000 years ago.

The world was experiencing a significant period of warming during that time, resulting in a dramatic dispersion of mammal species.  Beard said that in this ancient ice-free world, Alaska must have been a tropical paradise.

Mr. Beard reported his findings in the journal Proceedings of the National Academy of Sciences.  A summary of the report can be viewed at http://www.pnas.org/cgi/content/abstract/0710180105v1.


Photo Caption: Fossils of a new primate species called Teilhardina magnoliana were discovered in Mississippi. The mouse-size primate would have lived in trees along the coastlines about 55.8 million years ago, the researcher says. Credit: Mark A. Klingler/CMNH


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