Friday, January 22, 2010

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, ResearchBlogging.orgwe 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

15 comments:

JuliaL said...

I realize that this is a painfully ignorant question, but I haven't been able to find the answer: What does "kya" stand for?

Julien Riel-Salvatore said...

JuliaL: no worries - kya is (bad) shorthand for "thousand years ago".

Anne Gilbert said...

Wow! This is a *great* post! So a *very* big thank you for posting it.
Anne G

Julien Riel-Salvatore said...

Anne -
thanks!
JRS

Anne Gilbert said...

Just to letcha know, Dr. Riel-Salvatore, I'm tooting your horn wherever applicable. I think this is a very good archaeology blog!
Anne G

Andrew Oh-Willeke said...

A couple factors would seem to confound an inference of group size from sleeping area size.

1. Did Neaderthals post night watches? If not everybody sleeps at the same time because some are standing watch, the group is larger.

2. Was this a group of adults, or where there children? Children take less space and are prone to snuggle.

The indication that this was a stopping point for a Neanderthal group over some extended period of time also suggests that the general area would be a good place to look for coprolites, Neanderthal trash, preserved footprints, and the like.

I wonder if there is a way to type the source of ashes or smoke stains that might be left near a hearth to determine what was being burned.

Julien Riel-Salvatore said...

Andrew -
In response to the issues you raise, the number proposed by Vallverdu et al. is probably a minimum estimate of group size if anything, although it is interesting that their estimate (8-10 people) is larger than what ethnographic referents would suggest based on the number and distribution of hearths (4-6 people).

And given the general thoroughness of the Abric Romani crew, I'm fairly certain they've also looked in the rest of the area contained in the shelter for some of the evidence of human occupation you mention. That said, coprolites are probably more likely to be found away from the rockshelter, given some of the unpleasant corollaries inherent in their accumulation in or near living spaces.

As for what was being burned, the analysis of charcoal assemblages (i.e., anthracology) recovered from hearths can provide some useful data that directly informs us about those behaviors. This information was probably a bit too detailed to include in this preliminary report, although the authors do provide some detailed observations about the internal structure and thermal properties of the hearthes in Level N.

Anne Gilbert said...

Julien and Andrew:

Could be there was a designated place for, um, coprolites. Dog/wolves often have a designated place for such things; with wolves, it can be a territorial marker. Cats tend to bury theirs, maybe in the same place such as a cat pan if they are the domestic variety, or some place "outside" if they're wild members of the cat family. In any case, if members of the cat and dog families tend to "do their business" somewhere other than where they hang out, it would stand to reason that this is more or less an evolutionarily directed thing, and humans would pretty much have the same instincts. Mind you, I don't know anything about what nonhuman primates do about this. Archaeologically, I suppose if a team finds coprolites nearby, but not actually in the core area, they could be examined for bits of DNA or the like.
Anne G

onix said...

as i understand it the cave is just to small to fit a much larger nr. since just about every cave that was negotiable has been used for habitation a cave that would suit only 8 perople would generally be used by a small group. i don't think it is suggestive of anything then " neanderthalers also(!) lived in groups of only 6-8 (adult) indivduals." nice article. on a side note that enanderthalers ate fish i think follows also from several sttlements at rivermouths that suggest seasonal use and could hardly been meant for anything but catching salmon (i think those exist in portugal germany and russia (dunno where in russia tho) and its from emomory i havent seen it referenced in ages. (over 20 yrs thats why i point out)

Julien Riel-Salvatore said...

onix -
sorry for the delayed reply. Good point about the size of the cave. That said, what I think is important - and likely was what the authors may have been trying to emphasize - is that Neanderthals at least on occasion functioned in units of 6-8 people. If the function of the site can be accurately reconstructed (using inferred mobility patterns, chaine operatoire analysis, and use-wear of some of the tools found there), then we may be getting at very interesting dimensions of the organization of these foragers in that part of Mediterranean Spain. Your observations about the seasonal targeting of given animal resources would certainly fit in with this.

JRS

Anne Gilbert said...

Dr. Riel-Salvatore:

I am curious about this. My impression of Neandertals is, they tended to operate in relatively small group. Maybe 6-8 people, much of the time. I don't know, though. Is this supposed to be typical or atypical of them. And is there any evidence that they operated in larger groups, at least on occasion?
Anne G

Julien Riel-Salvatore said...

Anne -
good questions. My own perspective on this is that Neanderthal group size, much like their overall degree of behavioral complexity, tends to be systematiically underestimated, which leads to somewhat contradictory interpretations. For instance, on the one hand, Neanderthals are now often characterized as hyper-carnivores able to bring down large game like rhinos and mammoths (at least on occasion); yet, on the other, Neanderthal groups size is generally agreed to be very small, even though cooperative hunting by relative large groups of hunters would be needed for such hunting to be successful with any regularity. The truth of the matter is, we have little direct evidence about Neanderthal group size, except for a few glimpses like that from Abric Romani. In my view, there is strong circumstantial evidence that Neanderthals would almost certainly have had to operate in groups large than 6-8 individuals at least some of the time.

Anne Gilbert said...

Dr. Riel-Salvatore, thank you very much. My impression, FWIW, based only on the evidence from various digs, including that of Abric Romani, is that they tended to operate in fairly small "band-size" groups(e.g. family members, much like, say, a wolf pac), but certainly not all the time. I have also heard there is intriguing possible evidence for "aggregation sites"(maybe to hunt woolly mammoths or something like that)at places like La Ferrassie. But you're right, such evidence as exists, is certainly contradictory.
Anne G

Anonymous said...

Hi,
From the southern USA,(SC). Our Pastor,(baptist), teaches that the earth is only 3000 years old(3kya). The more I read, the more I disagree with his argument. He explains the dinosaurs as a huge hoax. Thank You for a little enlightenment.

Julien Riel-Salvatore said...

Hey there -
glad to help. Informing yourself is key. I hope you continue reading!

JRS