Optimal linear estimation models predict 1400–2900 years of overlap between Homo sapiens and Neandertals prior to their disappearance from France and northern Spain

Abstract

Recent fossil discoveries suggest that Neandertals and Homo sapiens may have co-existed in Europe for as long as 5 to 6000 years. Yet, evidence for their contemporaneity at any regional scale remains highly elusive. In France and northern Spain, a region which features some of the latest directly-dated Neandertals in Europe, Protoaurignacian assemblages attributed to Homo sapiens appear to ‘replace’ Neandertal-associated Châtelperronian assemblages. Using the earliest and latest known occurrences as starting points, Bayesian modelling has provided indication that these occupations may in fact have been partly contemporaneous. The reality, however, is that we are unlikely to ever identify the ‘first’ or ‘last’ appearance of a species or cultural tradition in the archaeological and fossil record. Here, we use optimal linear estimation modelling to estimate the first appearance date of Homo sapiens and the extinction date of Neandertals in France and northern Spain by statistically inferring these ‘missing’ portions of the Protoaurignacian and Châtelperronian archaeological records. Additionally, we estimate the extinction date of Neandertals in this region using a dataset of directly-dated Neandertal fossil remains. Our total dataset consists of sixty-six modernly produced radiocarbon determinations which we recalibrated using the newest calibration curve (IntCal20) to produce updated age ranges. The results suggest that the onset of the Homo sapiens occupation of this region likely preceded the extinction of Neandertals and the Châtelperronian by up to 1400–2900 years. This reaffirms the Bayesian-derived duration of co-existence between these groups during the initial Upper Palaeolithic of this region using a novel independent method, and indicates that our understanding of the timing of these occupations may not be suffering from substantial gaps in the record. Whether or not this co-existence featured some form of direct interaction, however, remains to be resolved.

Back to the future: The advantage of studying key events in human evolution using a new high resolution radiocarbon method

“…In fact, the calibrated age range of the Neanderthal of Fonds-de-Forêt in Belgium is 1,730 years (OxA-38322 14 C Age 39,500±1100 Tables 1 and 3 ), and it embeds chronologically two Homo sapiens from Bacho Kiro in Bulgaria (ETH-86769 14 C Age 39,750±380 span of 680 years, and ETH-86771 14 C Age 40,600±420 span of 1,060 years) ( Table 1 ). Therefore, the use of two different ranges of 14 C error in models (e.g., [ 66 ]) for claiming the temporal overlapping of the two species in two different regions should be viewed with some caution.…”

Homo floresiensisandHomo luzonensisare not temporally exceptional relative toHomo erectus

“…More importantly, the method provides a way to assess population structure in species and genera with temporally fragmented fossil discoveries. The surprise test therefore joins an increasing number of statistical methods that can improve our understanding of when and where different species were present using existing hominin fossil occurrences (Du et al , 2020; Bobe and Wood, 2021; Devièse et al , 2021; Key et al , 2021; Djakovic et al , 2022).…”

Hominins likely occupied northern Europe before one million years ago

“…Originally used to model the true extinction dates of species after their last sighting by humans, 70,72 the technique has since been widely applied and recommended within palaeontological extinction scenarios (e.g., 73–76 ). It is only recently that OLE modelling has been applied in the reverse temporal direction, having been employed to estimate origination ages for Oldowan, Acheulean and Protoaurignacian technologies 64,77 . Indeed, it is well known that archaeologists rarely (if ever) discover the first or last occurrences of past cultural phenomena.…”