Spanish cave yields remains of a human ancestor

[Al-khiyal]

Spanish cave yields remains of a human ancestor

March 26, 2008 -- Excavations in a cave in the mountains of northern Spain have uncovered the oldest known remains of human ancestors in Western Europe, scientists reported Wednesday.

The fossils of a lower jaw and teeth, more than 1.1 million years old, were found in sediments along with stone tools and animal bones that appeared to have been butchered. The remains have been attributed to the previously known species Homo antecessor, a possible ancestor of Neanderthals and modern humans.

The discovery is described in the current issue of the journal Nature by a team of Spanish and American scientists led by Eudald Carbonell of the Catalan Institute of Human Paleontology and Social Evolution at Tarragona, Spain.

The scientists, noting that the earliest presence of human ancestors in Europe is "one of the most debated topics in paleoanthropology," said the site of Sima del Elefante in the Atapuerca Mountains held the "oldest, most accurately dated record" of both fossils and artifacts of human occupation in Western Europe.

Other sites on the Continent have yielded artifacts of a roughly comparable age, but no fossil bones. Until now, the earliest remains of Homo antecessor, found in the same mountains, were 800,000 years old. Far to the east, in the Republic of Georgia, recent fossil discoveries show that early Homo had moved into parts of Eurasia from Africa about 1.9 million years ago.

"It's great to have confirmation that there was early human penetration in Western Europe this early," said Ian Tattersall, a paleonanthropologist at the American Museum of Natural History in New York, who was not involved in the research.

Tattersall said in an interview that it was too soon to tell where these cave occupants "fit in the larger scale" of early human settlement in Europe. It is not yet clear, for example, how or if this species was ancestral to later European populations, he said.

Carbonell's group conceded that the identification of the fossils as Homo antecessor was provisional. But those living in the cave had been busy making crude tools from chert, a dense quartz. A few pieces survived, along with flakes. The animal bones showed cut marks and other signs of processing, including fractures for extracting marrow.

[Al-khiyal]

Fossil find could be Europe's first humans

March 27, 2008 -- A fossilised jawbone and teeth found in a cave in northern Spain may have belonged to one of the first human ancestors to set foot in western Europe. The hominid has been identified as Homo antecessor, or pioneer man, a possible ancestor of both our own species and Neanderthals. The fossils date from between 1.1m and 1.2m years ago.

The find helps fill another gap in our understanding of the long march early humans made out of Africa. Stone tools and animal bones found with the hominid jaw also paint a vivid picture of the life of early cave-dwelling Europeans.

"The timing of the earliest human occupation of Europe has been controversial for many years," said Professor Chris Stringer, an expert in early humans at the Natural History Museum in London, who was not involved directly in the research. "[This find] suggests that southern Europe began to be colonised from western Asia not long after humans had emerged from Africa - something which many of us would have doubted even five years ago."

The fossils were discovered in the Sima del Elefante cave in Atapuerca in north-western Spain. Along with the hominid remains the research team found 32 rock fragments that were either stone tools or flakes produced by making the tools, suggesting that the hominids used the cave as a workshop among other things. There were numerous animal bones from a variety of species including rats, ferrets, bison, foxes, bears and big cats.

José Bermúdez de Castro at the National Research Centre on Human Evolution in Burgos, a member of the team that uncovered the fossils, said the early humans occupied a lush, warm, green paradise with plentiful water and lots of prey. The animal bones found suggest that humans at the site were eating meat. "We have evidence of cut marks on bones," he said. And in one case the jaw of a cow was broken to get at the succulent marrow inside. The find is detailed in Nature.

The hominid jawbone itself is probably from a female because it is small. Although the jaw fragment is not much to go on, from previous fossils the researchers can guess that the cave people would have been around 1.7 metres high (5ft 7in), with a brain three-quarters the size of ours.

Although the same species has been found at sites close to Sima del Elefante, the team are convinced this find is considerably older. They used three dating techniques to pin-point its age. These are based on past changes in the Earth's magnetic field, the known ages of other mammal species found with the jaw fragment and a new method that uses radioactive decay in sediments.

Not everyone is sure the fossil is H antecessor. The doubt stems from the fact that other finds of the species have not included jawbones for direct comparison.

Backstory

The question of when early humans made it into Europe is controversial. A large fossil collection from Dmanisi, Georgia, is dated to around 1.7m years ago. These are probably Homo erectus, a human species found mainly further east in Asia. Previously the oldest European fossils with convincing dates were from Gran Dolina, close to the new find in Atapuerca, Spain, and from Ceprano in Italy. These are around half the age of the new find.