西班牙从北部一化石中发现最古老的人类DNA
The site of Atapuerca, close to the city of Burgos in northern Spain, continues to produce fascinating news in regard to the origins of the human race.
A team of scientists have confirmed in a study published in the prestigious science magazine Nature this week that they have been able to extract DNA from the fossil of a hominid (bipedal human like creature) dated at 400,000 years old from the Middle Pleistocene era.
This makes the DNA sequence the oldest ever to be published and helps to place the fossils found at Atapuerca in the human family tree: a tree which appears to have many more branches than had been previously imagined.
It has long been thought that the 6,500 different fossils, discovered at the site known as the "the pit of bones" and thought to contain the remains of at least 28 individuals classified as the species Homo Heidelbergensis, belonged to a species ancestral to the Neanderthals.
The Neanderthals were a human species specialized to living in the cold climate of Western Europe, which became extinct less than 30,000 years ago and shared many characteristics with the fossils dug out of the pit of bones.
However, after comparing the DNA taken from the Atapuerca fossils to the genome of other relatives of our species, Homo Sapiens, it has been discovered that the Atapuerca individuals are genetically far closer to a population known as the Denisovans.
Very little is currently known about this group, who inhabited Siberia until 40,000 years ago.
Juan Luis Arsuaga, co-director of the Atapuerca site, said in the local press, "Everything points to there being far greater complexity in the Middle Pleistocene that we previously thought. We hope that further investigations will help to clear up the relationship between the fossils from the Sima, the Neanderthals and the Denisovians."
Findings at the site are dated to over 800,000 years ago and classified as Homo Antecessor, the origins of which is still to be fully explained. But theory is that it evolved from Homo Ergaster, a species which probably evolved in Africa and which could be an ancestor of our own species.
