Having the stomach for it: a contribution to Neanderthal diets?

Due to the central position of diet in determining ecology and behaviour, much research has been devoted to uncovering Neanderthal subsistence strategies. This has included indirect studies inferring diet from habitat reconstruction, ethnographic analogy, or faunal assemblages, and direct methods, such as dental wear and isotope analyses. Recently, studies of dental calculus have provided another rich source of dietary evidence, with much potential. One of the most interesting results to come out of calculus analyses so far is the suggestion that Neanderthals may have been eating non-nutritionally valuable plants for medicinal reasons. Here we offer an alternative hypothesis for the occurrence of non-food plants in Neanderthal calculus based on the modern human ethnographic literature: the consumption of herbivore stomach contents

Location, location, location: investigating perforation locations in Tritia gibbosula shells at Ksâr'Akil (Lebanon) using micro-CT data

Perforated shells are often used to study socially mediated behavior in past hunter-gatherer groups. The assumption is that their exclusive symbolic function makes them ideally suited to investigate social networks, dispersal activity, and social interaction. Before making any statements regarding human behavior, however, it needs to be established whether perforated shells from archaeological assemblages were used as personal ornaments. One of the key issues regarding beach-collected marine taxa is whether beached specimens were purposefully collected, e.g., preferentially selected naturally holed specimens, or whether human-made perforations may be identified. Past studies have investigated these questions by comparing datasets from modern death assemblages of shells with archaeological collections and through manufacture and use-wear analysis (e.g., Bouzouggar et al. 2007; Vanhaeren et al. 2006) This study introduces a novel approach using μCT scans of pristine shells to create a threedimensional model of shell thickness in Tritia (Nassarius) gibbosula. This model is used to map robust and fragile zones on shells of this taxon. The goal of this approach is to identify structurally weak zones that would be prone to natural perforations. Heat maps of shell thickness are then used to investigate perforation locations in modern natural death and archaeological assemblages. Our results show that in natural death assemblages, most perforations occur in structurally weak zones, and that their distribution is random. In our archaeological samples, from early Upper Paleolithic contexts at Ksâr ‘Akil, (Lebanon), we found that perforations in T. gibbosula mainly occur in structurally weak zones, but their distribution within these zones is not random and favors locations facilitating easy suspension (e.g., on cordage). This suggests that at Ksâr ‘Akil, T. gibbolusa shells were used as beads, and that shells with conveniently located natural perforations were intentionally sought for, that humans perforated the shells themselves, or that they used a combination of both. This in turn, warrants investigations into the social and behavioral implications of these perforated beads. Further aspects of human involvement with the shells should be explored, for example, through use-wear analysis

Tropical forager gastrophagy and its implications for extinct hominin diets

Reconstruction of extinct hominin diets is currently a topic of much interest and debate, facilitated by new methods such as the analysis of dental calculus. It has been proposed, based on chemical analyses of calculus, that Neanderthals self-medicated, yet this conclusion has been questioned. Gastrophagy has been suggested as an alternative explanation for the Neanderthal data, based on ethnographic analogies, which show this practice to have been widespread in traditional extant Homo sapiens diets, and nutritional evidence for its benefits at high latitudes. Here we expand the discussion of the potential importance of gastrophagy in human evolution by considering its role for an extant group of tropical foragers, the Hadza of Tanzania, and questioning its role in the diets of extinct tropical hominin species. Gastrophagy is frequently practiced among the Hadza and adult men in particular consume substantial, seasonally variable, amounts of prey guts. In addition to the important fact that gastrophagy is not a rare event, this demographic information may be useful in interpreting evidence from archaeological samples. The consumption of semi-digested chyme would have allowed extinct hominins to gain calories from plant sources without the cost of digesting them, possibly contributing to the encephalisation and shrinking of the gut in genus Homo. As an easy to process food-source, chyme could have likewise been an important food source for the old and the young, potentially playing a part in reducing inter-birth intervals and increasing reproductive success in our lineage. Thus gastrophagy may have played a key part in human evolution and its potentially confounding signal should be considered in future dietary reconstructions.We would like to thank The Calleva Foundation (LTB & CBS), The Human Origins Research Fund, NHM (LTB & CBS), The Leakey Foundation (JCB & BMW), Wenner-Gren Foundation (BMW), & the National Science Foundation (BMW) for funding.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.jasrep.2015.09.02

Tropical forager gastrophagy and its implications for extinct hominin diets

Reconstruction of extinct hominin diets is currently a topic of much interest and debate, facilitated by new methods such as the analysis of dental calculus. It has been proposed, based on chemical analyses of calculus, that Neanderthals self-medicated, yet this conclusion has been questioned. Gastrophagy has been suggested as an alternative explanation for the Neanderthal data, based on ethnographic analogies, which show this practice to have been widespread in traditional extant Homo sapiens diets, and nutritional evidence for its benefits at high latitudes. Here we expand the discussion of the potential importance of gastrophagy in human evolution by considering its role for an extant group of tropical foragers, the Hadza of Tanzania, and questioning its role in the diets of extinct tropical hominin species. Gastrophagy is frequently practiced among the Hadza and adult men in particular consume substantial

Identification of dermestid beetle modification on Neolithic Maltese human bone: Implications for funerary practices at the Xemxija tombs

Taphonomic modifications to Neolithic human skeletal remains from six rock-cut tombs in Malta has provided key information about funerary practices and the local environment. Application of microscopic analysis, computed tomography (CT) scanning, and 3D imaging of the modifications has allowed their comparison with similar examples in modern and archaeological skeletal material. The modifications are interpreted as pupal chambers and feeding damage by dermestid beetles. Based on observation of the behaviour and ecology of dermestid beetles, we suggest several scenarios for funerary practices at the Xemxija tombs which nuance our current understanding of collective burial during the late Neolithic in Malta.Magdalene College, Cambridg

Perforations in Columbellidae shells: Using 3D models to differentiate anthropogenic piercing from natural perforations

Perforated shells are often used to study socially mediated behaviour in past hunter-gatherer groups. One of the key issues regarding empty shells from beaches or fossil outcrops is determining human agency in the accumulation and modification of an assemblage. Here we investigate anthropogenic mediation in Initial Upper Palaeolithic and Early Ahmarian assemblages of Columbella rustica at Ksâr ‘Akil (Lebanon). We compare perforations in the archaeological specimens with data from newly gathered Columbellidae modern death assemblages from Tenerife (Spain) using three-dimensional shell-thickness models as templates. This approach, using micro-CT scans of pristine shells to map robust and fragile zones on shell outer-surfaces, allows us to contextualise the two datasets within their natural morphology. Our results show that in natural death assemblages the vast majority of perforations occur in structurally weak zones, and their distribution can be explained by shell morphology in combination with predator activity and other post-mortem damage. In our archaeological dataset we found a higher frequency of perforations in more robust zones and a higher uniformity in their location, size and shape. This suggests human mediation in either the selection or manufacture process of C. rustica beads at Ksâr ‘Akil from as early as the Initial Upper Palaeolithic and throughout the Early Ahmarian. Standardisation in perforation shape, size and distribution have been argued to be indicative of formalised manufacture processes and our results are thus more congruent with intentional bead manufacture than the selection of naturally-holed specimens

The Kabua 1 cranium: Virtual anatomical reconstructions

Our current knowledge of the emergence of anatomically modern humans, and the human lineage in general, is limited, in large part because of the lack of a well preserved and well dated fossil record from Pleistocene Africa. Thus, the primary aim of our research is to partly relieve this problem by virtually reconstructing and analyzing the hominin cranial remains of Kabua 1, found in Kenya in the 1950s. Most scholars have argued that Kabua 1 represents an anatomically modern Homo sapiens, although the fragmentary nature of the remains and lack of a chronometric date hinder robust phylogenetic and taxonomic assessments. This manuscript presents the first steps taken to resolve this issue, namely a set of reconstructions of the specimen that would allow comparison with the fossil record. First, we virtually removed sediment and laboratory adhesives from μct scans of the fragments. Subsequently, all fragments were separated by segmentation of the μct data and described. Finally, virtual surface projections were used in the creation of several anatomical reconstructions, based on separate reference crania. These first steps provide a framework that will be used for quantitative shape analyses that aim to more firmly place these remains in the context of human evolution

Evidence for habitual climbing in a Pleistocene hominin in South Africa

Bipedalism is a defining trait of the hominin lineage, associated with a transition from a more arboreal to a more terrestrial environment. While there is debate about when modern human-like bipedalism first appeared in hominins, all known South African hominins show morphological adaptations to bipedalism, suggesting that this was their predominant mode of locomotion. Here we present evidence that hominins preserved in the Sterkfontein Caves practiced two different locomotor repertoires. The trabecular structure of a proximal femur (StW 522) attributed to Australopithecus africanus exhibits a modern human-like bipedal locomotor pattern, while that of a geologically younger specimen (StW 311) attributed to either Homo sp. or Paranthropus robustus exhibits a pattern more similar to nonhuman apes, potentially suggesting regular bouts of both climbing and terrestrial bipedalism. Our results demonstrate distinct morphological differences, linked to behavioral differences between Australopithecus and later hominins in South Africa and contribute to the increasing evidence of locomotor diversity within the hominin clade

Inferring archaic introgression from hominin genetic data

Questions surrounding the timing, extent, and evolutionary consequences of archaic admixture into human populations have a long history in evolutionary anthropology. More recently, advances in human genetics, particularly in the field of ancient DNA, have shed new light on the question of whether or not Homo sapiens interbred with other hominin groups. By the late 1990s, published genetic work had largely concluded that archaic groups made no lasting genetic contribution to modern humans; less than a decade later, this conclusion was reversed following the successful DNA sequencing of an ancient Neanderthal. This reversal of consensus is noteworthy, but the reasoning behind it is not widely understood across all academic communities. There remains a communication gap between population geneticists and paleoanthropologists. In this review, we endeavor to bridge this gap by outlining how technological advancements, new statistical methods, and notable controversies ultimately led to the current consensu

Evidence of different climatic adaptation strategies in humans and non-human primates

To understand human evolution it is critical to clarify which adaptations enabled our colonisation of novel ecological niches. For any species climate is a fundamental source of environmental stress during range expansion. Mammalian climatic adaptations include changes in size and shape reflected in skeletal dimensions and humans fit general primate ecogeographic patterns. It remains unclear however, whether there are also comparable amounts of adaptation in humans, which has implications for understanding the relative importance of biological/behavioural mechanisms in human evolution. We compare cranial variation between prehistoric human populations from throughout Japan and ecologically comparable groups of macaques. We compare amounts of intraspecific variation and covariation between cranial shape and ecological variables. Given equal rates and sufficient time for adaptation for both groups, human conservation of non-human primate adaptation should result in comparable variation and patterns of covariation in both species. In fact, we find similar amounts of intraspecific variation in both species, but no covariation between shape and climate in humans, contrasting with strong covariation in macaques. The lack of covariation in humans may suggest a disconnect in climatic adaptation strategies from other primates. We suggest this is due to the importance of human behavioural adaptations, which act as a buffer from climatic stress and were likely key to our evolutionary success