by Aaron Jonas Stutz

Research on big issues in human evolution–like how Neandertals contributed to our own genetic diversity and to ancient cultural diversity … before they went extinct–certainly involves a level technical nitty gritty that even specialists in the field get worn down by. But sooner or later, we get back up, ready to geek out on the details again. For those of you interested and with institutional access, please check out our newly published article on radiocarbon dating the earliest Upper Paleolithic in the Levant. This is the first major publication on our work on the Mughr el-Hamamah site–work that has been led my Liv Nilsson Stutz and myself … but which has depended on and succeeded thanks to extensive collaboration (Stutz et al., in press). The article may be viewed here, although–as noted above–full access to this Journal of Human Evolution content requires a subscription, so you may be limited to the abstract:

http://www.sciencedirect.com/science/article/pii/S0047248415001050?np=y

Liv Nilsson Stutz provides a narrated overview of the article here:

http://audioslides.elsevier.com//ViewerLarge.aspx?source=1&doi=10.1016/j.jhevol.2015.04.008

In addition, Emory University’s inimitable Carol Clark has published an great overview of the work here: http://esciencecommons.blogspot.com/2015/06/stone-tools-from-jordan-point-to-dawn.html

In this post, I emphasize the key findings from our collaborative research on the Mughr el-Hamamah site, Jordan, and its importance for understanding the beginning of the Upper Paleolithic. I also offer a brief peek at work to come. Continue reading Measuring the Beginning of the Upper Paleolithic →

Or: It’s All About Evolution, Not Revolution …

by Aaron Jonas Stutz

We’re now paying particular attention to research on the Protoaurignacian, including the notable recent report by Benazzi et al. (2015). We’ll get to their report below. Let’s start with the Protoaurignacian fuss in the first place. There’s pretty good scientific reason for it. Around 2006, Paul Mellars and João Zilhão–two prehistoric archaeologists who otherwise don’t agree about much–separately presented very similar suggestions, which have turned out to be very influential. In a series papers they separately argued that the Protoaurignacian archaeological artifact pattern–or technocomplex, which I will describe in a bit more detail below–has a clear relationship to anatomically modern human expansion into western Eurasia around 40,000 years ago.

Mellars (2006) suggested that the Protoaurignacian artifact pattern is actually a key component of a complex archaeological marker that traces anatomically modern human colonization of western Eurasia … and thus, also of Neandertal extinction.

Zilhão (2006) argued the same thing about anatomically modern humans, but he suggested that anatomically distinctive Neandertals–as opposed to some Neandertal features inherited by some Early Upper Paleolithic people with mainly anatomically modern ancestry–persisted in parts of Europe until ca. 30,000 years ago. On the one hand, there’s no clear threshold of how many unique derived Neandertal traits you need to be “distinctively Neandertal.” On the other, Zilhão and others pointed out that in Iberia, there are some quite distinctively Neandertal fossils, for which a series of radiocarbon dates had placed at roughly 30 kya. The problem now is that those C14 dates were made on incompletely chemically cleaned and filtered collagen-like material surviving in those bones (Wood et al., 2013, 2014). It turns out that all of the Iberian Neandertals so far re-analyzed with the collagen ultrafiltration pretreatment are actually closer to 50-45 kya in age, associated with Middle Paleolithic stone tools.

But what’s important for investigating the Protoaurignacian archaeological phenomenon is that Zilhão’s hypothesis overlaps significantly with Mellars’s. And if the joint Mellars-Zilhão version is right, then there are two very important observations we would expect to be able make … leading to more complete understanding of anatomically modern human / Neandertal biological turnover (a.k.a. Neandertal extinction). First, the oldest Protoaurignacian-like artifact assemblages should be found closer to the African geographic origin of anatomically modern human populations–that is to say, in the Near East. Second, hominin fossils associated with Protoaurignacian archaeological deposits should have anatomically modern–rather than Neandertal–features. Continue reading The Protoaurignacian Didn’t Trigger Anything →

… and about the Biocultural Evolution of Paleolithic Technological Systems in General

by Aaron Jonas Stutz

Human adaptation and niche alike are defined in major part by technology. We use our bodies to shape and transform our material surroundings, fundamentally to extract food resources, but often to create things that we then utilize with our bodies to shape other things, including our own bodies. Technology really changes the way our bodies intertwine with and experience the environment.

Our tool-using primate relatives–and tool use is quite common in the primate order–mainly employ technologies that are expedient (Bently-Condit & Smith, 2010). Perhaps with the exception of stone hammer-and-anvil nut cracking, observed mainly in some chimpanzee communities (Haslam et al., 2009), primate tool-users do not go out of their way to provision themselves with raw materials or finished, modified tools, as they go about planned foraging tasks over a period of hours. Rather, facing an immediate challenge in extracting food or water, primates take–and sometimes quickly, slightly transform–materials in their immediate vicinity, in order to solve that challenge. This happens in a matter of seconds or minutes. Continue reading Learning about the Protoaurignacian →

… But Most of Us Are a Little

by Aaron Jonas Stutz

Every single one of us on Earth today is, by definition, an anatomically modern human. We differ a lot from the Neandertal anatomical pattern that–despite variations among individuals–generally prevailed across western Eurasia some 50,000 years ago. It stands to reason that it would have taken some time for evolution to have shaped the anatomical features that we all now share. It’s reasonable to expect that, going back well into the last Ice Age–which ended 12,000 or so years ago–our ancestors would have also been anatomically modern human, not Neandertal.

The fossil record suggests that the founding anatomically modern human populations were distributed through Africa, extending into the Levant, just outside of Africa, all between 200-100 thousand years ago (see Wolpoff & Lee, 2012, for a scholarly discussion). But bits of intact DNA extracted from ancient Neandertal and anatomically modern human bones alike confirm–with remarkable specifics –what some paleoanthropologists have generally been arguing for decades (Thorne & Wolpoff, 1992). Our ancestry isn’t so simple. Continue reading Why None of Us Are Very Neandertal →