Two studies published this week in the journals Nature and Nature Ecology & Evolution report the discovery and dating of human remains, game, bone and stone tools and jewelry attributed to Homo sapiens. These fossil hominin remains from the Bacho Kiro cave in Bulgaria are the earliest known European evidence ofHomo sapiens in the Upper Paleolithic [1].
Arriving in Europe around 45,000 years ago, modern humans(H. sapiens) gradually took the place of the Neanderthals. This period of population replacement is known as the transition from the Middle Paleolithic to the Upper Paleolithic. The precise course of events during this transition period is the subject of much debate today, mainly due to the paucity of fossil remains that can be directly, accurately and reliably dated.
In the article published in Nature, Jean-Jacques Hublin and his colleagues describe hominin remains and artifacts discovered in the Bacho Kiro cave in Bulgaria. These include a tooth that has been attributed to H. sapiens, as well as four other bone remains identified as belonging to humans thanks to the collagen and DNA they still contain.
An initial carbon-14 dating method, described in the article published in Nature Ecology & Evolution, suggests an age range of between 46,940 and 43,650 years. A second method, based on the analysis of mitochondrial DNA extracted from these bones, gives estimates ranging from 44,830 to 42,616 years, and corroborates the carbon-14 dating.
The excavations also uncovered a number of items of jewellery, including bear tooth pendants that resemble those found at other, more recent sites associated with Neanderthal activity. These results show that modern humans expanded into the mid-latitudes of Eurasia before 45,000 years ago. Straddling the range of the Neanderthals, they exerted an influence on the latter's behavior before replacing them.
Dating human remains attesting to the presence of the first modern humans in Europe: a collaboration between the Max-Planck Institute (Leipzig) and the CEREGE in Aix-en-Provence.
For the rarest and most precious artefacts in archaeology, such as human remains, tools and bone sculptures, the destruction of samples required for classical dating using gas pedal mass spectrometry (AMS) would cause irreparable damage. TheCO2 gas ion source of the AixMICADAS spectrometer overcomes this constraint thanks to the very small sample sizes, which represent 5 to 50 micrograms of carbon and contain on the order of a few zeptomoles of 14C(Tuna et al. 2018). AixMICADAS was recently installed (Bard et al. 2015) on the Technopôle de l'Arbois campus as part of the EQUIPEX ASTER-CEREGE project led by CEREGE (UMR Aix-Marseille Université, CNRS, IRD, INRAE, Collège de France).
The Max Planck Institute for Evolutionary Anthropology in Leipzig (Helen Fewlass and Sahra Talamo from the Department of Human Evolution headed by Jean-Jacques Hublin) and CEREGE (Thibaut Tuna and Yoann Fagault, researchers attached to the Climate and Ocean Evolution chair at Collège de France occupied by Édouard Bard) have developed a new approach to dating collagen purified from human bones. The first step was to establish an optimal method for synthesizingCO2 from collagen using an elemental analyzer and a zeolite trap coupled to the AixMICADAS ion source (Fewlass et al., 2018, 2019a). In a second step, this new method was used to date purified collagen samples from fragments of human remains from famous sites such as the Dolni Vestonice triple human burial in the Czech Republic (Fewlass et al. 2019b) and the Bacho Kiro cave in Bulgaria (Fewlass et al. 2020), for which the same 14C-datedhuman bones were the subject of genetic and proteomic analyses (Hublin et al. 2020).
The AixMICADAS gaseousCO2 ion source, which enables us to work on very small samples, offers the possibility of improving the purification of bones and charcoal, which represents a real revolution in the dating of archaeological sites.
