Oldest Human Ancestor Fossil Found

"This leads us to a very important, very interesting conclusion," Carbonell said. It is this: that hominins which emerged from Africa and settled in the Caucasus eventually evolved into Homo antecessor, and that the latter populated Europe not 800,000 years ago, but at least 1.3 million years ago.

"This discovery of a 1.3 million-year-old fossil shows the process was accelerated and continuous; that the occupation of Europe happened very early and much faster than we had thought," Carbonell said.

Chris Stringer, a leading researcher in human origins at the Natural History Museum in London and not involved in the project, said Carbonell's team had done solid dating work to estimate the antiquity of the new Atapuerca fossil by employing three separate techniques -- some researchers only use one or two -- including a relatively new one that measures radioactive decay of sediments.

"This is a well-dated site, as much as any site that age can be," Stringer said.

But he also expressed some caution about Carbonell's conclusions.

First of all, the newly found jawbone fragment, which measures about two inches long and has teeth attached to it, preserves a section not seen in the equivalent pieces found at Atapuerca in 1997. So assigning both to the same species must be provisional, Stringer said.

And on the broader issue of tracing the new fossil back to the species unearthed at Dmanisi -- Carbonell's big leap arguing continuity -- Stringer said this too must be tentative because it is based on just a piece of a front of a jawbone, and the time lapse is half a million years.

"That is a long period of time to talk about continuity," Stringer said.

Still, there are similarities between the two, and this along with other archaeological evidence suggests southern Europe did in fact begin to be colonized from western Asia not long after humans emerged from Africa -- "something which many of us would have doubted even five years ago," Stringer said.

Carbonell says that with the finding of human fossils 1.3 million years old in Europe, researchers can now expect to find older ones, even up to 1.8 million years old, in other parts of the continent.

"This has to be the next discovery," he said. "This is the scientific hypothesis."

Related Links:

Jennifer Viegas' blog: Born Animal

How Human Migration Works

The Hall of Human Ancestors

Early Human Phylogeny