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. References External links Nat. Geo., Oldest Primate Fossil in North America Discovered. 3 March 2008; retrieved 22 August 2008 Prehistoric primate genera Eocene primates Cenozoic mammals of Europe Fossil taxa described in 1940 Prehistoric mammals of North America Fossil taxa described in 2008 Taxa named by George Gaylord Simpson Fossil taxa described in 1993 Fossil taxa described in 2004