New dating research led by Griffith University has confirmed the great antiquity of fossil remains attributed to a species of human called Homo antecessor found in Spain.
The research, published in Quaternary Geochronology, describes the first direct dating study of Homo antecessor fossil remains found within Unit TD6 at Atapuerca Gran Dolina site, Spain.
The fossil has been directly dated to between 772,000-949,000 years ago, which is consistent with previous indirect estimates and makes it the oldest known fossil human species in Western Europe. While a few older human fossils have been found in Western Europe, they could not be attributed to any specific species, in contrast with the Gran Dolina remains.
The work, led by Dr Mathieu Duval and Professor Rainer Grün, researchers at Griffith’s Australian Research Centre for Human Evolution (ARCHE), involved an international team from Spain, Australia, France and China and brought together international experts of various disciplines such as Geochronology, Palaeoanthropology, Geology and Archaeology.
The archaeological Unit TD6 at the Gran Dolina site has been excavated since the 1990s and delivered about 160 hominin fossil remains, all attributed to a single species, H. antecessor.
One tooth was selected from this fossil record and dated by Electron Spin Resonance (ESR). The results were combined with a new palaeomagnetic study of the sediments of Unit TD6, which provided an age range of 772,000-949,000 years for the fossil. This age confirms the antiquity of Homo antecessor and associated lithic industry, which had been previously obtained from the dating of the sediments and associated mammal fossil teeth from TD6.
“We faced many challenges during this study, and without the active participation of all these specialists, it would not have been possible to obtain any meaningful and reliable result,” Dr Duval said.
“We had to use the most advanced analytical techniques to date this tooth fragment, and had to go several times to the site in order to accurately reconstruct the sedimentary environment” adds Professor Rainer Grün.
The position of Homo antecessor in the human fossil lineage and whether it could be the ancestor of our species, Homo sapiens, is still a source of debate within the palaeoanthropology community.
The age obtained in the present study predates the estimated age for the population split of modern and archaic human lineages derived from genetic studies. This would make it a plausible candidate for the last common ancestor of H. neanderthalensis and H. sapiens according to some palaeoanthropologists, although further investigation is required to confirm this hypothesis.
Mathieu Duval, Rainer Grün, Josep M. Parés, Laura Martín-Francés, Isidoro Campaña, Jordi Rosell, Qingfeng Shao, Juan Luis Arsuaga, Eudald Carbonell, and José María Bermúdez de Castro. The first direct ESR dating of a hominin tooth from Atapuerca Gran Dolina TD-6 (Spain) supports the antiquity of Homo antecessor.
This work has received funding from the European Union Marie Curie International Outgoing Fellowship PIOF-GA-2013-626474 and the Australian Research Council Future Fellowship FT150100215, both granted to Mathieu Duval.
The Australian Research Centre for Human Evolution, which sits within based in Griffith’s Environmental Futures Research Institute, is the first academic centre specifically focused on gaining a deeper understanding of the scale of ancient human migrations and the full story of the origins of the people in our region. An initiative of Queensland’s Griffith University, ARCHE’s mission is to foster research excellence through multidisciplinary projects that bring together leading Australian and international scholars and institutions in the field of human evolution. In particular, one of the research focus consists of dating archaeological occupations and especially fossil remains. ARCHE has played a key role in some of the most important recent discoveries associated to the origin of our species, Homo sapiens, with the direct dating of key human fossils from Jebel Irhoud (Morocco), Misliya cave (Israel), Al Wusta (Saudi Arabia) and other human species like Homo floresiensis (known as the “Hobbit”, Indonesia), Homo naledi (South Africa), and now Homo antecessor.