Evidence has come to light of the grim fate of a Neanderthal family group that lived in Spain 49,000 years ago. After apparently enduring a lifetime of privation, they were killed and eaten by members of a neighbouring Neanderthal group – presumably themselves on the brink of starvation and thus driven to extremities.
In 1994, extensive human remains were found at El Sidrón, an extensive system of karstic limestone caves in the Asturias region of northern Spain. Systematic excavation commenced in 2000 and to date around 1800 hominin skeletal fragments and 400 Mousterian-type stone tools have been recovered. The latter include side scrapers, denticulate pieces, a hand axe, and several Levallois points. The human remains are thought to represent twelve Neanderthal individuals, including three adult males, three adult females, three male adolescents and two juveniles and an infant of unknown gender.
A group size of 12 individuals at El Sidron is reasonably consistent with a previous estimate of between 8 to 10 individuals per Neanderthal group, based on the size of sleeping and combustion activity areas in the long-occupied rock shelter of Abric Romaní, near Barcelona. However, because the original external deposit cannot be studied, it could not be rules out that the El Sidrón group was larger and that some original members are not represented among the remains.
The tools and remains were found in a side gallery deep within the cave complex, and was probably introduced into the cave from the surface when a violent storm caused an upper gallery or a series of fissures to collapse. Pebbles and clay were also dragged down from the surface. The whole assemblage is around 49,000 years old. Around 18 percent of the tools have been refitted, suggesting that they are all the same age and that the associated human remains represent all or part of a contemporaneous social group of Neanderthals, who died at around the same time.
The low temperature of the side gallery meant that genetic material has survived and mitochondrial DNA has been extracted from each of the individuals. It was found that all three of the adult males carried the same mitochondrial lineage, but the three adult females all carried different lineages. Mitochondrial DNA is not a part of the primary genome and is inherited solely from the maternal line. The implication, therefore, is that the males shared the same maternal lineages but the females all had different maternal lineages. This suggests that in Neanderthal groups, mature males remained within their family birth group, but females came from outside. Patrilocality, as it is known, is present in about 70 percent of modern human societies, where men remaining in the family home but women move to the home of their new husband upon marriage.
But there is a darker side to the discoveries. All the El Sidrón individuals suffered from developmental stress, or periods of growth arrest, presumably arising from malnutrition. This is indicated by deficiencies in dental enamel, present on over 50 percent of the group members’ incisors, canines and premolars and over 30 percent of their molars. Five of the members had experienced two such episodes of growth arrest and one adult had experienced four. It is clear that for this extended Neanderthal family, life was very difficult – and in the end, it seems, they met a grim fate.
Cut marks and breaks have been found on many of the bones, including lower jawbones, skulls and long bones; evidence of skinning activity and extraction of bone marrow and brains – in other words, cannibalism.
References:
Lalueza-Foxa, C., Rosas, A., Estalrrich, A., Gigli, E., Campos, P., García-Tabernero, A., et al. (2010, December). Genetic evidence for patrilocal mating behavior among Neandertal groups. PNAS .
Rosas, A., Martınez-Maza, C., Bastira, M., Garcıa-Tabernero, A., Lalueza-Fox, C., Huguet, R., et al. (2006). Paleobiology and comparative morphology of a late Neandertal sample from El Sidron, Asturias, Spain. PNAS , 103 (51), 19266–19271.
Vallverdu, J., Vaquero, M., Caceres, I., Allue, E., Rosell, J., Saladie, P., et al. (2010). Sleeping Activity Area within the Site Structure of Archaic Human Groups Evidence from Abric Romanı Level N Combustion Activity Areas. Current Anthropology , 51 (1), 137-145.
© Christopher Seddon 2010
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