800,000-year-old teeth reveal ‘ancient relative’
A NEW DNA sequencing method using teeth has helped shed fresh light on some ancient “relatives”.
Scientists extracted genetic data from an 800,000-year-old tooth belonging to a member of the Homo antecessor – “Pioneer man”– species.
They were able to reach back in time by double the previous record thanks to a state-of-the-art molecular sequencing method.
Researchers in Denmark are now confident that Homo antecessors were a sister group to the last common relatives of modern humans, cooling a long-standing debate among scientists.
Evidence
Study author Dr Frido Welker, at Copenhagen University, said: “Ancient protein analysis provides evidence for a close relationship between Homo antecessor, us (Homo sapiens), Neanderthals, and Denisovans.
“Our results support the idea that Homo antecessor was a sister group to the group containing Homo sapiens, Neanderthals, and Denisovans.”
The obsolete human species lived in Western Europe (Spain, England and France) between about 1.2 million and 800,000 years ago.
Researchers sequenced DNA from ancient dental enamel unearthed during a 1994 dig at Sierra de Atapuerca, in northern Spain. The new molecular method, called palaeoproteomics, enables scientists to retrieve evidence to accurately track human evolution from further back than ever before.
Study co-author Professor Jesper Velgaard Olsen, from Copenhagen University, said: “Using state of the art mass spectrometry, we determine the sequence of amino acids within protein remains from Homo antecessor dental enamel.
“We can then compare the ancient protein sequences we ‘read’ to those of other hominins, for example Neanderthals and Homo sapiens, to determine how they are genetically related.”
The human and the chimpanzee lineages split from each other about nine to seven million years ago, the researchers explained.
Scientists have relentlessly sought to better understand the evolutionary relations between our species and the others, all now extinct, in the human lineage.
It is believed Homo antecessor became extinct in Europe, perhaps replaced by another early human species, then by Neanderthals from around 400,000 years ago and finally by modern humans.
Scientists have intensely debated the relation between Homo antecessors and other human groups.
New studies confirmed that Homo antecessor’s facial features are very similar to those of Homo sapiens and very different from those of the Neanderthals.
Lead author Enrico Cappellini said he was happy the study “provides evidence that the Homo antecessor species may be closely related to the last common ancestor of Homo sapiens, Neanderthals, and Denisovans.The features shared by Homo antecessor with these hominins clearly appeared much earlier than previously thought.
Homo antecessor would therefore be a basal species of the emerging humanity.”