Neanderthal wooden structures, sleeping areas and group size at Abric Romaní

Well, what do you know... it looks as though Neanderthals in Mediterranean Spain were up to all sorts of interesting stuff ca. 55-50kya! Hot on the heels of the news that ornaments and coloring materials were found in Mousterian deposits at Cueva Anton and Cueva de los Aviones, we get news that Neanderthals at Abric Romaní (Spain, near Barcelona) appear to have had well defined sleeping areas that bear striking resemblance to those found in rockshelters used by extant hunter-gatherers (Vallverdú et al. 2010). But wait, there's more! The evidence reported by Vallverdú et al. (2010) also includes the impression of a ca. 5m-long worked wooden post (see image below) likely used as part of some kind of ephemeral wooden structure like a lean-to or a hut/tent pole. And as if that wasn't enough, an analysis of the hearths and occupied area suggests that level N (dated to ca. 55kya by U series) formed as the result of repeated occupations by small groups of 8-10 hominids who used the for brief periods of time, one of the first empirically derived for Neanderthal group size.

From Vallverdú et al. (2010:141) - color image available from the

online edition of Current Anthropology.

There's a lot to digest in that preliminary report. First, the sleeping areas. This is important since it relates to the structured use of space, which is often argued to be something that differentiates modern humans from Neanderthals. Of course, the recent paper on Lower Paleolithic spatial organization at Gesher Benot Ya'aqov in Israel has done a lot to dispel that preconception lately, but it's still framing how many researchers conceptualize Neanderthals. The Romaní investigators identified 19 hearths in Level N (you can see them as the dark patches in the picture above), and identified that they were arranged in three distinct areas within the rockshelter: inner (closest to the backwall), frontal (around the largest travertine accumulations), and frontal (in the center of the shelter). An analysis of the hearths indicates that they were used repeatedly in a smouldering manner for brief periods of time. As well, the distance between the hearth and the distance between the hearths and the backwall in the inner zone all combine to "suggest that this space represents a sleeping-and-resting area in the Romaní record (Vallverdú et al. 2010:142). As the authors emphasize, there is a small but growing number of studies that have documented similar types of spatial organization at other Middle Paleolithic sites, including notably Tor Faraj, Jordan (Henry et al. 2004). These all suggest that Neanderthals were able to segregate their activities as well as to use the thermal characteristics of shallow hearths and rockshelter morphology to create comfortable sleeping areas, including at sites like Abric Romaní that faces N/NE and would not have mostly shaded and humid without such effective accommodations.

The wooden pole that the authors describe was identified on the basis of its impression in travertine deposits (see part b of the picture above which also shows what appears to be the pattern created by bark on the impression). "The travertine wood imprint measures 510cm in length and 6cm in width at one end and 3cm at the other. It has a rectilinear form, an absence of branches, and it ir fragmented, indicating probably that this piece of wood was subject to human modifications" (Vallverdú et al. 2010:140). Its position at the edge of the inner zone which is where evidence for a sleeping area was identified suggest to the authors that it was part of some sort of larger structure, maybe "a simple triangular structure leaning against the wall' (Vallverdú et al. 2010:143). Here, I'll simply point out that there is evidence for wooden structures at other Middle Paleolithic (and by extension Neanderthal) sites in Europe, including notably at the site of La Folie, France (which I discussed at length in another post), and which dates to ca. 57.2kya, roughly the same age as Level N at Abric Romaní.

The aspect of the paper which I thought was especially thought-provoking concerns the estimation of Neanderthal group size. Based on the size of the inner zone, the authors "assume that a density of individuals using 1.5-2m2 each or a group of 8-10 hominids could occupy this area. Hearth spacing in sleeping areas [based on ethnographic examples - JRS] suggests an occupation number of 4-6 individuals." (Vallverdú et al. 2010:143). While this estimate is extremely interesting in light of what it may tell us about Neanderthal social organization, before people go out and use this paper to show that Neanderthals lived in extremely small groups, it is important to emphasize that this group size is characteristic of fleeting occupations of the site. If anything, this may be telling us something about the size of task group (or some similar social unit) more than anything about overall group size in Neanderthals. If Level N at Romaní reflects a satellite site to a larger 'home base' type settlement, then we may start extrapolating from that 8-10 person figure some more grounded estimates of the extent of Neanderthal social units broadly speaking. Fascinating.

References

Henry, D. O., H. J. Hietala, A. M. Rosen, Y. E. Demidenko, V. I. Usik and T. L. Armagan. 2004. Human Behavioral Organization in the Middle Paleolithic: Were Neanderthals Different? American Anthropologist 106:17-31.

Vallverdú, J., Vaquero, M., Cáceres, I., Allué, E., Rosell, J., Saladié, P., Chacón, G., Ollé, A., Canals, A., Sala, R., Courty, M., & Carbonell, E. (2010). Sleeping Activity Area within the Site Structure of Archaic Human Groups Current Anthropology, 51 (1), 137-145 DOI: 10.1086/649499