Our Earliest Primate Ancestors Were Tree-Dwelling Mouse-Like Creatures That Existed 55 Millions Years Ago

Posted by Milton Recht:

From The Wall Street Journal "Fossil of Unusual Human Ancestor Discovered" by Gautam Naik:

Fossil Found of Tree-Dwelling Human Ancestor

Researchers have identified a nearly complete skeleton of an unusual, tree-dwelling ancestor of humans that lived 55 million years ago, a discovery that illuminates one of the earliest stages of our evolution. Shown, an artist's depiction of Archicebus achilles, Chinese Academy of Sciences.

Researchers have identified a nearly complete skeleton of an unusual, tree-dwelling ancestor of humans that lived 55 million years ago, a discovery that illuminates one of the earliest stages of our evolution.

Unearthed in China, the mouse-sized creature has a mix of anatomical features that make it quite unlike any other primate—living or extinct—known to science. The discovery was published Wednesday in the journal Nature.

By about 55 million years ago, the earliest primate ancestors of humans had split into two branches. One branch gave rise to lemurs, lorises and bush babies. The other led to tarsiers, whose enormous-eyed, tree-dwelling descendants still live in Southeast Asia. The second branch also gave rise to anthropoids, including monkeys, apes and humans.

The animal described in the study is a primitive tarsier relative. It is of interest to scientists because it lived at a crucial period, fairly soon after the two branches split.