We separated ourselves from chimps 4 million years ago. This took place in Africa. And after that, the rest of the world became a place for African colonists. When did these colonists enter Europe? We do not know for sure, but now Spanish archaelogists have discovered the oldest fossil tooth ever found in Western Europe.

The early-human molar was found last Wednesday at the Sierra Atapuerca archaeological site in the Burgos Province (northern Spain), not very far from the famous Altamira cave.

Caves at the site, found 15 mi (25 km) east of the city of Burgos, have already revealed other ancient human remains. Human fossils discovered in the proximity in 1994 pointed that humans had inhabited Europe as early as 800,000 years ago, 300,000 years before it was previously believed.

But the new tooth is even more ancient: its age was fixed at around 1.2 million years old, like that of stone tools and animal fossils bearing human-tool cut marks found at sites in Spain, France and Italy.

"Now we finally have the anatomical evidence of the [early humans] that fabricated tools more than one million years ago," stated the team from Atapuerca Foundation.

The team is waiting for final analysis of the tooth and hopes for further findings, even if the chances are small, as teeth preserve better than bones.

"Since it is an isolated fossil remain, it is not possible at this point to confirm which Homo species this tooth belongs to," the team said.

The first analyses "allow us to suppose it is an ancestor of Homo antecessor," they said.

Homo antecessor ("pioneer" human) is described based on fossils discovered in the 1990s and dated to be 800,000 years old and could be the same with Homo ergaster, the last common ancestor of modern humans and Neanderthals.

It could also be the same with Homo heidelbergensis, which appeared some 600,000 years ago and which is strongly related to Neanderthals.

"The fossil appeared to be well worn and from an individual between 20 and 25," said Jose Maria Bermudez de Castro, one of three experts that conducted the latest excavation, told the AFP news agency.

The same site contained bison, bears, deer and monkey fossils. The remains of an extinct mouse species encountered at the site suggested the age of the human tooth by offering a time frame of the period when the individual could have lived.

The oldest fossils of H. antecessor, found in 2002, come from 1.7-million-year-old human skulls dug at the Dmanisi site (Georgia).