Who inhabited the Jubbah lake in the Nefud Desert during the Middle Paleolithic?

Many readers may have heard of the Nefud Desert while watching Lawrence of Arabia (was that filmed on location?). It is hard to imagine that desolate landscape as being instrumental in the tale of human origins, but it may very well have been. A new paper describes Middle Paleolithic settlement evidence from the Jubbah Palaeolake, especially during MIS stages 7 and 5.

Arabia is a very interesting case for a variety of reasons: It has to be implicated one way or another in the tale of human origins and dispersals: it lies in the natural route Out-of-Africa, and in the intermediate space between the early modern human remains from Ethiopia, the later modern humans from the Levant, as well as the disputed late Neandertals of West Asia.

Unfortunately, current climatic conditions, as well as past episodes desiccation have resulted in substantial population; if anyone wanted to find out what the people who lived there during the Middle Paleolithic were like, he will find little continuity between them and the current inhabitants. The lack of genetic evidence is, unfortunately also accompanied by a general lack of anthropological evidence. Industries with links to Africa or the Levant are devoid of associated remains. But, the paper produces a hopeful note:

Yet, recent support for an MIS 5 expansion of Homo sapiens comes from archaeological finds of characteristic Middle Palaeolithic technologies in Arabia in MIS 5e–c [19]–[20] and nuclear genomic estimates which indicate that the split between Africans and non-Africans occurred as early as 130 to 90 ka [41], consistent with fossil finds of Homo sapiens in the Levant [52], [53] and at the time of possible interbreeding of Homo sapiens and Neanderthals [54]. These controversies indicate the need to recover hominin fossils in Arabia, which is feasible given the identification of Pleistocene mammalian fauna in a nearby lake basin of the Nefud [24], [55].

In the absence of genes or bones, we can only make inferences based on stones, which may not have a direct correspondence with populations. While Figure 17 from the paper (left) shows a clear differentiation of India vis a vis. the west, relationships in the Near East and Africa are not as clear cut; Skhul resembles North Africa (Haua Fteah and Aterian) and it would be tempting to associate them with Homo sapiens. But, Horn of Africa MSA  -where the earliest anatomically modern humans were found- is linked to El Wad, Tabun C, and Jebel Qattar/Katefeh, the latter two sites being the ones from the Nefud.

Tabun is associated with Neandertals, although that attribution, like most everything in palaeoanthropology is controversial.So, it might be possible that the Jubbah was occupied by Neandertals too, and this might make this population a prime candidate for the signal of Neandertal admixture carried by non-Africans.

At present, there seem to be two candidates for the modern human Out-of-Africa: Skhul (Levant; linked to Northwest Africa here) and the Nubian technocomplex of (south Arabia; linked to Northeast Africa). I don't have a clear picture of how it may have all played out; it would certainly be wonderful if it were possible to extract DNA from, say, Skhul/Qafzeh modern humans or the Levantine Neandertals, because that would definitely show how (i) the former may either be related to later Eurasians, or may be a failed experiment as hitherto supposed, and (ii) the latter might be a source of Neandertal DNA in non-Africans, or indeed something much closer to modern humans as their morphological intermediacy might suggest.

PLoS ONE 7(11): e49840. doi:10.1371/journal.pone.0049840

Hominin Dispersal into the Nefud Desert and Middle Palaeolithic Settlement along the Jubbah Palaeolake, Northern Arabia

Michael D. Petraglia et al.

The Arabian Peninsula is a key region for understanding hominin dispersals and the effect of climate change on prehistoric demography, although little information on these topics is presently available owing to the poor preservation of archaeological sites in this desert environment. Here, we describe the discovery of three stratified and buried archaeological sites in the Nefud Desert, which includes the oldest dated occupation for the region. The stone tool assemblages are identified as a Middle Palaeolithic industry that includes Levallois manufacturing methods and the production of tools on flakes. Hominin occupations correspond with humid periods, particularly Marine Isotope Stages 7 and 5 of the Late Pleistocene. The Middle Palaeolithic occupations were situated along the Jubbah palaeolake-shores, in a grassland setting with some trees. Populations procured different raw materials across the lake region to manufacture stone tools, using the implements to process plants and animals. To reach the Jubbah palaeolake, Middle Palaeolithic populations travelled into the ameliorated Nefud Desert interior, possibly gaining access from multiple directions, either using routes from the north and west (the Levant and the Sinai), the north (the Mesopotamian plains and the Euphrates basin), or the east (the Persian Gulf). The Jubbah stone tool assemblages have their own suite of technological characters, but have types reminiscent of both African Middle Stone Age and Levantine Middle Palaeolithic industries. Comparative inter-regional analysis of core technology indicates morphological similarities with the Levantine Tabun C assemblage, associated with human fossils controversially identified as either Neanderthals or Homo sapiens.

Link

ESHE 2012 abstracts

Some abstracts of interest from the European Society for the study of Human Evolution 2012 meeting (pdf). To avoid making this too long, I will just post the titles and the most relevant quotes. You can read the abstracts in the linked pdf for authors names and more information.

Neandertal and Denisovan Genomes from the Altai 

Susanna Sawyer  et al.

In 2010 a draft genome sequence was determined from a small finger bone found in Denisova Cave in southern Siberia. Its analysis revealed that it derives from an individual who belonged to a population related to, but distinct from, Neandertals. A molar has also been described from Denisova Cave and has shown to carry an mtDNA genome closely related to that of the finger bone.  We have recently determined the DNA sequence of the Denisova genome to a quality similar to present-day human genomes. We have also retrieved a complete mitochondrial genome and nuclear DNA sequences from an additional molar found in Denisova Cave. Furthermore, we have determined a high-quality nuclear genome from a pedal phalanx found in Denisova Cave in 2010. We show that the pedal phalanx derived from a Neandertal and thus that Neandertals as well as Denisovans have been present in the cave. We will discuss the genetic history of Denisovans as well as Neandertals in light of these new genome sequences. 

The discovery of a Neandertal genome from Denisova cave is certainly interesting. I have previously commented that:

If Vindija and Denisova, two caves less than 5,000km apart were home to people more divergent from each other than any two humans are today, it's strange to think that only "modern humans" inhabited Africa at the same time.

Now, it appears that Neandertals and Denisovans were present (when?) not only 5Mm apart, but literally on the same spot. Much later, during the Neolithic we see very differentiated humans co-existing in Europe. And, we get archaic hominins in Africa long after the appearance of anatomically modern humans there. I think the evidence is looking good for my hypothesis that regional human populations have recently gotten more similar over time through extensive admixture between divergent hominin groups, rather than that they became more dissimilar over time  through tree-like divergence.

On the same topic, here is more evidence for Neandertal presence in the Altai:

A Neanderthal mandible fragment from Chagyrskaya Cave (Altai Mountains, Russian Federation)

Both the mandible and the dentition preserve numerous derived Neanderthal traits: among else a posteriorly placed mandibular foramen, an oblique mylohyoid line, an asymmetrical P4 and continuous mid-trigonid crests on the M1 and M2. ... Ongoing ancient DNA analyses of the hominin remains from Chagyrskaya cave and absolute dates for the site will hopefully help to clarify the origin of the Altai Neanderthals, and their relationship with the Denisovans.

An hypothesis for the phylogenetic position of Homo floresiensis

Our cladistic analysis places H. floresiensis unequivocally as part of a clade with H. habilis

Who are you calling ”modern”? An assessment of the dental morphology and metrics of Homo sapiens

Although dental reduction has long been cited as a derived feature of H. sapiens, our data indicate this claim may be no longer tenable ... the single metrical assessment that groups all H. sapiens (early, Upper Paleolithic and recent) apart from other taxa is the ratio between mandibular:maxillary crown areas.  the results of our study are important for assessing recent claims of great antiquity for H. sapiens outside of Africa

Neanderthal in Malthusian demographic trap

It can be hypothesized that the demography of the Neanderthal metapopulation, living under conditions where extreme environmental instability with short periods was the norm, was primarily stagnant,

with frequent bottlenecks and episodes of decline.

 A New Framework for the Upper Paleolithic of Eastern Europe

The results of field and laboratory research during the past decade require a new classificatory framework for the Upper Paleolithic in Eastern Europe. It is now apparent that people making artifacts assigned to the Ahmarian industry occupied both the southern and northern slopes of the Caucasus Mountains (i.e., Ortvale Klde, Layer 4d; Mezmaiskaya Cave, Layer 1C). Their sites probably indicate a separate movement of anatomically modern humans (AMH) from the Near East directly into Eastern Europe, establishing an independent line of development during the earlier Upper Paleolithic that parallels the Proto-Aurignacian and Aurignacian sequence in Western and Central Europe. this East European industry is most fully represented at the Kostenki-Borshchevo sites on the Don River before 40,000 cal BP (e.g., Kostenki 14, Layer IVb). It is followed by a closely related industry, also characterized by bladelet production, that is dated to the interval between 40,000 and 30,000 cal BP in Crimea and the East European Plain. The proposed new framework reflects recognition of these distinctive East European entities and of two environmental events that had significant impacts on human settlement in Eastern Europe: (1) the Campanian Ignimbrite (CI) volcanic eruption (40,000 cal BP); and (2) the Last Glacial Maximum (LGM) ( 25,000 cal BP). It has been suggested that the early Upper Paleolithic (EUP) industry present in Eastern Europe before 40,000 cal BP should be labeled an eastern variant of the contemporaneous Proto-Aurignacian of Mediterranean Europe. However, given the separate movement of people from the Near East via the Caucasus Mountains, and independent development of the East European EUP, this industry is more appropriately termed “Proto-Gravettian.” The younger bladelet industry, which includes assemblages at Buran-Kaya III (Layer 6-1), Mira (Layer II/2), Kostenki 8 (Layer II), and probably Shlyakh (Layers 4C, 6), may be termed “Early Gravettian” to distinguish it from the classic Gravettian industry that dates to less than 30,000 cal BP (e.g., Avdeevo, Zaraisk).The upper temporal boundary of the Proto-Gravettian corresponds to the CI eruption (40,000 cal BP), while the classic Gravettian of the East European Plain appears to have been effectively terminated by the LGM ( 25,000 cal BP). Several sites that date to the 40,000–30,000 cal BP interval (e.g., Kostenki 1, Layer III) contain elements that suggest a connection with the Aurignacian technocomplex of Western-Central Europe. These assemblages may be placed into the category of “Eastern Aurignacian,” which reflects differences in content with the West and Central European sites. The apparent spread of this industry into Eastern Europe from Central Europe may be related to the impact of the CI eruption on portions of the East European Plain. 

 Conflicting dates for the Late Aterian

First at the huge Ifri n’Ammar sites, TL dates have indicated 80,000 years for the Late Middle Palaeolithic/Aterian levels. Our new C14 dates yield 35,000 BP for exactly the same levels. At the “grotte des Contrebandiers”, formerly dated at 28,000 BP by Debenath and his team, is now dated at 100,000 years by new TL dates. As starting points, this kind of methodological contradiction should be confronted, understood and resolved.

 The Rio Secco Cave in the North Adriatic Region, Italy. A new context for investigating the Neanderthal demise and the settllement of Anatomically Modern Humans

A sequence of several thin layers dated to 46.0–42.1ky Cal BP represents the final Mousterian.

The Dhofar Nubian Tradition: an enduring Middle Stone Age technocomplex in southern Arabia

Between 2010 and 2012, the Dhofar Archaeological Project has located and mapped 260 Nubian Complex occurrences across the Nejd Plateau of southern Oman. Diagnostic Nubian artifacts werefound cemented in fluvial sediments at the site of Aybut Al Auwal in Dhofar, with two OSL dates around 106 ka BP; hence, roughly contemporaneous with the African Nubian Complex (Rose et al. 2011). Many of these lithic assemblages, such as that from Aybut al Auwal, are technologically homologous to the Late Nubian Industry found in northeast Africa, sensu stricto, while others may represent local facies of the greater “Afro-Arabian Nubian Technocomplex.” This presentation describes the various reduction strategies encountered at a sample of Nubian Complex sites from Oman, explores inter-assemblage variability, and begins to articulate technological units within the “Dhofar Nubian Tradition.” To achieve this aim, we have developed an analytical scheme with which to describe technological variability among Nubian Levallois reduction strategies in both Africa and Arabia. Our analysis indicates at least two distinct Nubian industries. The first, which we refer to as the “Classic Dhofar Nubian,” is virtually identical to Late Nubian Industry from the Lower Nile Valley and Red Sea Hills in Egypt. Thee subsequent group of assemblages in Dhofar, called the “Mudayyan,” exhibits a technological shift toward diminutive Nubian Levallois cores and that, recurrent bidirectional cores with opposed, faceted striking platforms. We interpret this evidence to indicate an enduring, local Nubian tradition in Dhofar that is ultimately rooted in the African Nubian Complex. 

From Late Mousterian to Evolved Aurignacian: New evidence for the Middle-to-Upper Paleolithic transition in Mediterranean Spain

Combined, the evidence from CA and FDM indicates that, in chronostratigraphic terms, the Middle-to-Upper Paleolithic transition in Murcia consists of the replacement of a Late Mousterian by an Evolved Aurignacian and occurred some time during the 38th millennium cal BP

The function of the Aterian

From the paper:

The ability of human hunters to ‘kill at a distance’ [1], [2] is often considered one of the hallmarks of modern human behavior. Such an ability embodies the cultural transcendence of the human body's condition with the aid of technology and has deep implications for the self-understanding of our species's uniqueness in the animal kingdom. For this reason, the search for evidence of projectile weapon technologies in the Stone Age has superseded the search for evidence of mere hunting activities, the latter having slid in the background of pre-human hominin behavioral repertoire [3]–[5]. Because ‘safe hunting’ is considered to have given anatomically-modern humans a competitive advantage against Neandertals during the last Out-of-Africa event (e.g., [6], [7]), it is extremely important to rigorously examine claims for the existence of such technologies, even when the superficial examination of the morphology of a particular tool suggests a clear functional determination. Such is the case of the Aterian tanged (or stemmed) point, a type of stone tool found throughout North Africa in a variety of ecological, geographical, and chronological contexts within the African Middle Stone Age (MSA), and which exhibits a simple form that is sometimes reminiscent of stemmed arrowheads or spear points from much later time periods (Figure 1). ... The importance of correctly interpreting the function of Aterian stemmed tools is underlined by recent dating results, which suggests that, contrary to early assumptions, it could date to as early as MIS 5 and before [29]. More specifically, new dates from a series of sites, such Mugharet el-Aliya [30], Rhafas [31], Ifri n'Ammar [29], Dar-es-Soltan [32], and Contrebandiers [33] have demonstrated that tanged tools can be found in the earliest part of the North African Middle Stone Age, making them potentially the earliest evidence of prehistoric stone-tipped weaponry. However, the precise way in which they actually fit within a prehistoric technological system, including whether or not they were part of flying projectile armatures or thrusting spears, has never been rigorously determined, despite the crucial role that both projectiles and hafting are thought to play in the evolution of human cultural adaptations.
...
Several lines of evidence point in the direction of progressive resharpening of Aterian tools in the same manner as edge-tools such as scrapers and cutting-tools. This does not per se rule out an initial use for some Aterian pieces as weapon tips, because the ultimate use of each individual tool must be determined by the examination of use-traces, and because each episode of retouch likely wipes out previous uses of the tool. However, the data presented here make a strong case for the claim that, in general, these tools were probably hafted and used repeatedly for tasks that resulted in the need to rejuvenate edges rather than point-tips. The comparison between excavated, mostly cave contexts, and surface sites reveals that they both contain similar reduction trajectories and shape variabilities of tanged tools. This indicates that the functional emphasis on the tools was similar during their use-life in the landscape and at the repeated-occupation sites, which contradicts the expectations of breakage and repair patterns associated with a use as projectile tips [62], [63].
...
It is thus possible that hafting was practiced on both sides of the Mediterranean Sea, but in different ways. Although some of the differences in technological innovation between archaic and modern humans that we observe at the continental and species level may be due to cognitive differences or to demographic factors influencing the spread and accumulation of information [79], [80], we must not forget the essentially functional character of toolkits. Especially when comparing and evaluating technologies at very large scales, functional responses to specific technological problems (such as prey size and behavior [1] or increased risk associated with prey frequency and ease of hunting (e.g., [81]–[84])) may trump other factors. Even if the ultimate cause underpinning technological change is a large-scale environmental phenomenon, such as a rapid cooling event, or the aridity of a newly-colonized area, we can understand these associated changes only by unraveling the constraints imposed on toolkits by the subjects of the actions for which the tools themselves were used. Thus, perhaps the better question to answer regarding the Aterian might not be if it represents the earliest hunting weapons technology, but rather, in what way it arose out of new challenges posed by the environments that characterized North Africa since MIS 5, and how it adapted during the almost 100 thousand years of occupation of this region.

PLoS ONE 6(12): e29029. doi:10.1371/journal.pone.0029029

Shape Variation in Aterian Tanged Tools and the Origins of Projectile Technology: A Morphometric Perspective on Stone Tool Function

Radu Iovita

Abstract

Background Recent findings suggest that the North African Middle Stone Age technocomplex known as the Aterian is both much older than previously assumed, and certainly associated with fossils exhibiting anatomically modern human morphology and behavior. The Aterian is defined by the presence of ‘tanged’ or ‘stemmed’ tools, which have been widely assumed to be among the earliest projectile weapon tips. The present study systematically investigates morphological variation in a large sample of Aterian tools to test the hypothesis that these tools were hafted and/or used as projectile weapons.

Methodology/Principal Findings Both classical morphometrics and Elliptical Fourier Analysis of tool outlines are used to show that the shape variation in the sample exhibits size-dependent patterns consistent with a reduction of the tools from the tip down, with the tang remaining intact. Additionally, the process of reduction led to increasing side-to-side asymmetries as the tools got smaller. Finally, a comparison of shape-change trajectories between Aterian tools and Late Paleolithic arrowheads from the North German site of Stellmoor reveal significant differences in terms of the amount and location of the variation.

Conclusions/Significance The patterns of size-dependent shape variation strongly support the functional hypothesis of Aterian tools as hafted knives or scrapers with alternating active edges, rather than as weapon tips. Nevertheless, the same morphological patterns are interpreted as one of the earliest evidences for a hafting modification, and for the successful combination of different raw materials (haft and stone tip) into one implement, in itself an important achievement in the evolution of hominin technologies.

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