Quote of the day: Matt Cartmill on evolutionary laws

From the inimitable Matt Cartmill:

"The trick in discovering evolutionary laws is the same as it is in discovering laws of physics or chemistry-namely, finding the right level of generalization to make prediction possible. We do not try to find a law that says when and where explosions will occur. We content ourselves with saying that certain sorts of compounds are explosive under the right conditions, and we predict that explosions will occur whenever those conditions are realized."

Paleoanthropology: Science or Mythical Charter? (2002: 193)

Archaeology and pepper spray

Pepper spray has been in the news for all the wrong reasons these past few days, after being used unnecessarily on UC Davis students protesting tuition hikes and income inequality. Several professors have already bravely denounced this chilling excessive violence by police, and Rosemary Joyce (a Berkeley archaeologist) gives us a bit of context on the long history of how chili by-products have been used as tools of coercion in pre-Columbian Mexico:

In a sixteenth-century painted manuscript today known as the Codex Mendoza, a few pages depict what are represented as norms of raising children among the Mexica of Central Mexico (commonly referred to as the Aztecs). These idealizations-- which should be thought of as formal idealizations, not norms-- include the actions that children were threatened with if they were not compliant with authority. We have no way of knowing if these actions were ever carried out, or how often: but what is clear is that they were corporal punishments. And primary among them was exposing a defiant child to the smoke from burning chili peppers.

That relationship-- of domination by threat of punishment-- is what, for me, hovers in the background every time pepper spray is used by police on the people. And policing should not be punishment.

For an interesting, eye-opening and shocking review on the history and true potency of pepper spray, you should also check out this very informative post by Deborah Blum.

Write, and write right!

This piece from a couple of years ago and entitled "Righting your writing" has been making the rounds in my FB network. It provides a pretty good series of tip/strategies for scientists to write more clearly. One that stood out to me was the one about developing daily writing habits

Write daily for 15 to 30 minutes
During your daily writing sessions, don’t think about your final manuscript. Just write journal entries, says Tara Gray, director of the teaching academy that provides training and support to New Mexico State University professors. “People think there’s two phases of a research project—doing the research and writing it up,” she says. Rather than setting aside large chunks of time for each activity, combine them to improve your writing and your research. The first time Gray encouraged a group of faculty members at New Mexico State to adhere to this schedule for three months, they wrote about twice as much as their normal output.

I can't emphasize how important this is. For one thing it builds discipline about getting something on the page everyday. For another, it does wonders to declaw the idea that writing has to be perfect on the first go-around. What I mean by this, it that it makes writing a lot less daunting if you do it habitually, and train yourself to expect that for every 10 words you write, you may end up keeping only one or two in the end. Even if you keep just that fraction, it adds up over time into lines, paragraphs, pages, sections, chapters and even dissertations. In a way, it's really just the academic equivalent of Stephen King setting daily writing goals of 1,000 or 2,000 words (King 2000), except that here you're writing to get in the habit of writing about your work, not fiction, and to fit that habit in the rest of your day.

This is incidentally the key piece of advice from J. Bolker's Writing Your Dissertation in Fifteen Minutes A Day (Bolker 1998). I rarely recommend books as must-reads for graduate students, since everyone's trajectory and style is so different. Bolker's book is one of the few exceptions to this general rule: it really does a wonderful job of showing the importance and, frankly, the healthiness of making writing a routine exercise as opposed to something that is better saved for intense bursts. Now - spoiler alert - the book doesn't actually show you how to write your dissertation (or thesis, or paper, or whatever) in 15 minutes a day. But it does provide a really clear framework for how to think about and structure your writing, and especially developing healthy writing habits. And the key thing about this is also what T. Gray mentions in the quote above: in my experience, approaching writing in this way does allow you to write more and write better overall. It also provides you with a much better use of your time for those 15-30 minutes 'dead periods' between classes or meetings than just surfing the net!

That said, I don't know about the 'journal entry' approach advocated by Gray, but to each is own. Frankly, the important thing is really just to write something, anything daily. It may sound silly, but for a great many people, it works and it helps make the whole process of academic writing that much easier and, dare I say it, appealing.

References

Bolker, J. 1998.Writing Your Dissertation in Fifteen Minutes a Day: A Guide to Starting, Revising, and Finishing Your Doctoral Thesis.Owl Books, NY.

King, S. 2000. On Writing: A Memoir of the Craft. Scribner, NY.

Neanderthals shellfishing 150,000 years ago

The news is out: the site of Bajondillo, in southern Spain, has yielded clear evidence of Neanderthals collecting and eating shellfish as far back as 150,000 years BP, and pretty much continuously, though at different intensities, after that. One obvious thing to point out: this is almost as old as the earliest evidence of modern humans collecting shellfish (Marean et al. 2007), and the way Neanderthals did it seems to have been constrained by very similar considerations, namely how far the beach was from a given site in the past. The paper itself (Cortés-Sánchez et al. 2011) is published in PLoS ONE, which means that it's freely accessible.

Today's kind of a hectic day (giving a free, non-technical talk at the Colorado Scientific Society tonight, levaing for a trip tomorrow), but this paper is a real game changer on several levels, so check back soon, cause I'll have much, much more to say about this. Exciting times for Neanderthal Studies, I'll tell you that much!

References

Cortés-Sánchez M, Morales-Muñiz A, Simón-Vallejo MD, Lozano-Francisco MC, Vera-Peláez JL, et al. 2011 Earliest Known Use of Marine Resources by Neanderthals. PLoS ONE 6(9): e24026. doi:10.1371/journal.pone.0024026

Marean CW, Bar-Matthews M, Bernatchez J, Fisher E, Golberg P, et al. (2007) Early human use of marine resources and pigment in South Africa during the Middle Pleistocene. Nature 409: 905–908.

A Mousterian wooden spade from Abric Romani, Spain

A group of researchers from the IPHES (Institut Català de Paleoecologia Humana i Evolució Social) reports on the discovery of a handheld wooden implement from Mousterian deposits at Abric Romaní, Spain. The tool was found in Level P which dates to about 56,000 years BP, and its morphology suggests that it might have been a small spade/shovel, or perhaps a poker, given its association to a hearth. In the interest of clarity, let me emphasize that what was recovered is actually a travertine impression of that tool. However, that impression is so detailed that it was possible to identify the precise morphology and dimensions of the spade- or poker-like object (I actually think it looks more like some kind of spatula or knife - it'd be interesting to run some experimental work on the functional and ergonomic properties of this object), as well as the fact that it was made out of the wood of a coniferous species, likely pine.

A view of the travertine impression found in Level P, along with a reconstruction of the wooden object that left it.
© Jordi Mestre/IPHES.

Detail of the impression of the Level P wooden object. © Jordi Mestre/IPHES

This is not the only wooden object that was recovered from the Mousterian levels of Abric Romaní. For example, last year, I discussed the finding of a worked wooden pole that was likely used as part of a structure in level N dating to ca. 55kya (Vallverdu et al. 2010). In that case, the impression indicates that the object was over 5m in length, and shows clear evidence of having been whittled down to a specific morphology, namely that it is devoid of branches, and that it shows a slight tapering from 6cm in width at its base to 3cm in width at its top. This pole-like morphology suggests to Vallverdu et al. (2010: 143) that it was probably used as part of a structure like a fairly simple lean-to.


What I didn't discuss in that post is that there are other levels at Abric Romaní that have yielded evidence of wooden implements: Level H (~45-49kya) contained two dish-like wooden objects (one  32cm by 22cm in dimensions, the other about 22cm by 17cm and elliptical in outline). The larger object was made of juniper wood, and it was flat on its underside and bore a depression in the center of its top surface, reinforcing the idea it might have been a vessel of some sort. That level also yielded a third wooden object. This one was also flat, but displays a pointed end. This odd morphology made it more difficult to attribute it a possible function, but it certainly suggest that it had been worked by humans. These finds are described in details by Carbonell and Castro-Curel (1992). 

Three years later, the same researchers reported on the existence of wood pseudomorphs from Level I at Abric Romaní (Castro-Curel and Carbonell 1995). This layer dates to about 46-49kya, again the tail-end of the Mousterian in the region. In contrast to Level H, it wasn't wood fragments per se that were recovered in Level I, but rather hollows in the travertine that were later filled with plaster to produce casts of the objects that decayed and left their (very detailed) impression in the travertine at the site. Here, one of the pseudomorphs was a worked, tapering tree trunk (3.5m in length, 109cm wide at its base, 45cm wide at the top - both ends of the tree had been hacked off in the Mousterian). But the most striking recovery in that level is that of Pseudomorph 2, which was a set of three straight, rod-like pieces of wood recovered in a roughly triangular arrangement overlying a hearth. It was interpreted by the authors as most likely representing a tripod used in 'food processing' - probably cooking/boiling  (Castro-Curel and Carbonell 1995: 378). 

So, what's the big deal about this new find? Well, a few things. First, it's the only object like it known from the Paleolithic. There are other wooden implements known from a few sites - for instance, the well-known Schoeningen spears (Thieme 1997) - but this is, to my knowledge the first evidence of such a portable pointed object clearly intended to be used in one hand. Its morphology is also unique: according to a report in El Mundo that provides additional information on the find, its handle was 17cm long by 4cm wide, while its 'blade' was 15cm long by 8cm wide, and triangular and pointed in outline. Given that there is now plenty of evidence that some stone tools were hafted by Neanderthals, it should come as no surprise that there are functionally distinct components in this tool. However, what is really striking is that, in spite of Paleolithic archaeologists' obsession with stone tools, Neanderthals seem to have been perfectly content to use wood as the 'active' component of at least some of their tools.

Second, along with the other evidence for use of wooden objects at Abric Romaní, it suggest that the use of wood as a building material was a constant of Neanderthal adaptation. The importance of this is not fully appreciated since wood only rarely preserves, but the peculiar sedimentary conditions at Romaní (especially the conspicuousness of carbonate/travertine accumulations) give us an unparalleled look at the prevalence and diversity of how wood was used by Neanderthals for other things than fueling fire and hafting stone tools. Although naysayers will point out that one of the most common traces of use identified on stone tools has been linked to woodworking, I've never felt that researchers gave those observation their full consideration. Finding actual wooden implements shows what Neanderthals might have been making out of wood, and the range of these objects found at Romaní broadens our view of how diverse and important wood technology must have been for Middle Paleolithic foragers.

Lastly, it tells us something about how Neanderthals considered some of their material culture. In this instance, there is no indication that the object was broken. Yet, it seems to have been discarded rather unceremoniously by tossing it into a smouldering and partly extinguished fire (per El Mundo) that only partly carbonized it instead of consuming it completely. While we lack information about how Level P was occupied (i.e., was it occupied, say, long-term as a base camp, or fleetingly as a task site), the find indicates that there were certain contexts in which Neanderthals were perfectly OK with the notion of discarding objects that were still usable. Maybe spade/pokers like this one were relatively easy to manufacture and were considered unimportant or too bulky to be worth carrying from one site to another. Whatever the case may be, it suggests some labor-intensive objects could be considered disposable at least under certain circumstance, and it provides us with a really provocative glimpse into the nature and breadth of Neanderthal technology and how they thought of it.

Via: Millán Mozota.

References

CARBONELL, E., & CASTRO-CUREL, Z. (1992). Palaeolithic wooden artefacts from the Abric Romani (Capellades, Barcelona, Spain) Journal of Archaeological Science, 19 (6), 707-719 DOI: 10.1016/0305-4403(92)90040-A  

Castro-Curel, Z., & Carbonell, E. (1995). Wood Pseudomorphs From Level I at Abric Romani, Barcelona, Spain Journal of Field Archaeology, 22 (3), 376-384 DOI: 10.1179/009346995791974206  

Thieme, H. (1997). Lower Palaeolithic hunting spears from Germany Nature, 385 (6619), 807-810 DOI: 10.1038/385807a0  

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

Svante Pääbo lecture on his recent genetic work

TED has a video up of Svante Pääbo discussing his (team's) recent research on the genetics of Late Pleistocene human populations. It's a good primer on the latest work on Neanderthal and Denisovan DNA, and their implications for the relationship of these populations to early modern humans.

Multimillennial Neanderthal occupation at La Cotte de St. Brelade

The BBC has a brief news story about some of the results of new excavations conducted at the site of La Cotte St. Brélade (Jersey, Channel Islands). The site is perhaps most famous for having yielded clear evidence for the systematic slaughter of mammoths and wooly rhinos by Neanderthals, which prompted a reevaluation of their hunting abilities (Scott 1980). That analysis, however, suggested that these animals were accumulated at the site over brief timespans.

The question of how long Neanderthals occupied La Cotte is where the overview of this new research project gets especially interesting:

"La Cotte's collapsed cave system contains intact ice age sediments spanning a quarter of a million years, revealing a detailed sequence of Neanderthal occupation and occasional abandonment, against a background of changing climate.

"The site is the most exceptional long-term record of Neanderthal behaviour in North West Europe," says Dr Matt Pope from the Institute of Archaeology at University College London.

"At La Cotte, we get to see far more than a glimpse of their behaviour, we get to see generation upon generation of Neanderthals returning to the same place under lots of different environmental conditions."

In other words, this new fieldwork (including investigations at other sites, btw) is shedding very interesting new light on how Neanderthals occupied the sites under different conditions, and - most importantly - why their behavior varied over time. As someone who's argued for a long time for the need to develop methods that allow us to develop long-term diachronic perspectives in order to understand the full range of Paleolithic lifeways (e.g. Riel-Salvatore and Barton 2004, Riel-Salvatore et al. 2008), I'm very excited about such reports. It'll also be extremely interesting to see how the artifacts collected in older excavations compare to those found by the new project. This new project, incidentally, has a nifty little web site that provides a lot of pertinent information about the new project at La Cotte and nearby sites, as well as other components of their research agenda, including some underwater survey. Check out The Quaternary Archaeology and Environments of Jersey project (which includes one team member who's commented on this blog before).

References

Riel-Salvatore, J., & Barton, C. (2004). Late Pleistocene Technology, Economic Behavior, and Land-Use Dynamics in Southern Italy American Antiquity, 69 (2) DOI: 10.2307/4128419

RIEL-SALVATORE, J., POPESCU, G., & BARTON, C. (2008). Standing at the gates of Europe: Human behavior and biogeography in the Southern Carpathians during the Late Pleistocene Journal of Anthropological Archaeology, 27 (4), 399-417 DOI: 10.1016/j.jaa.2008.02.002

Scott, K. (1980). Two hunting episodes of middle Palaeolithic age at La Cotte de Saint-Brelade, Jersey (Channel Islands) World Archaeology, 12 (2), 137-152 DOI: 10.1080/00438243.1980.9979788