45,000-year-old pelvic bone indicates unknown human lineage

The cave is a significant site for explorations and excavations of the Châtelperronian lithic industry and Neanderthal remains. The tools unearthed represent the Châtelperronian techno-cultural complex, which arose during the transition period.

The cave is evidence that Neanderthals developed characteristics of modern human behavior before establishing contact with them. But this notion is disputed since later human artifacts have been found in the site mixed with Neanderthal remains.

The researchers compared the pelvic bone to two known infant Neanderthal hip bones and also with 32 human deceased neonates. The study's authors noted that the shape of the iliac bone differed from the Neanderthal bones and is much more in line with the AMH era.

However, the study noted that the hip is also not in line with modern human infants, displaying “a more laterally oriented posterior-superior iliac spine,” stated the study.

“We propose that this is due to its belonging to an early modern human lineage whose morphology differs slightly from present-day humans,” wrote the authors in their study.

A hybrid industry

The researchers suggest that if their observations are validated, it will prove that the tools from the Châtelperronian techno-cultural complex, extending from northern Spain to the Paris Basin, resulted from cultural diffusion or acculturation processes with possible population admixture between the two groups.

Under such a scenario, AMHs would have developed the tools, and Neanderthals would have copied their innovations. They also might have modified them to suit their own unique needs, explained a report by Phys.org.

The study is published in the journal Scientific Reports.

Study abstract:

Around 42,000 years ago, anatomically modern humans appeared in Western Europe to the detriment of indigenous Neanderthal groups. It is during this period that new techno-cultural complexes appear, such as the Châtelperronian that extends from northern Spain to the Paris Basin. The Grotte du Renne (Arcy-sur-Cure) is a key site for discussing the biological identity of its makers. This deposit has yielded several Neanderthal human remains in its Châtelperronian levels. However, the last inventory of the paleoanthropological collection attributed to this techno-complex allowed the identification of an ilium belonging to a neonate (AR-63) whose morphology required a thorough analysis to assess its taxonomic attribution. Using geometric morphometrics, we quantified its morphology and compared it to that of 2 Neanderthals and 32 recent individuals deceased during the perinatal period to explore their morphological variation. Our results indicate a morphological distinction between the ilia of Neanderthals and anatomically modern neonates. Although AR-63 is slightly outside recent variability, it clearly differs from the Neanderthals. We propose that this is due to its belonging to an early modern human lineage whose morphology differs slightly from present-day humans. We also explore different hypotheses about the presence of this anatomically modern neonate ilium among Neanderthal remains.