KobehCavePresentation_0.pdf
- Author (aut): Mealer, Danielle
- Thesis director: Marean, Curtis
- Committee member: Fahey, Patrick
- Contributor (ctb): Barrett, The Honors College
- Contributor (ctb): School of Human Evolution & Social Change
The analysis of fragmentation and surface modification on a large and unbiased sample of faunal remains associated with the Mousterian deposits from Kobeh Cave (Zagros Mountains, Iran) is key to assigning a primary accumulator to each stratigraphic unit and discerning changes in accumulator over time. The Mousterian is a stone tool industry associated with Neanderthals, thus, the Kobeh assemblage informs us on this extinct hominin’s foraging behavior. This assemblage is affected by a significant level of post-depositional destruction. The frequency of surface modifications were compared to frequencies of surface modifications from experimental and naturalistic contexts to infer a primary accumulator. Cut marks were the most prevalent surface modification in this assemblage followed by tooth marks and percussion marks, suggesting a complex taphonomic history of accumulating actors. All stratigraphic units showed evidence of hominin and carnivore activity, though hominins are identified as the primary actor. There is evidence that the Middle Top Unit saw significant contribution by carnivores independent of scavenging.
The coastal environments of South Africa’s Cape Floristic Region (CFR) provide some of the earliest and most abundant evidence for the emergence of cognitively modern humans. In particular, the south coast of the CFR provided a uniquely diverse resource base for hunter-gatherers, which included marine shellfish, game, and carbohydrate-bearing plants, especially those with Underground Storage Organs (USOs). It has been hypothesized that these resources underpinned the continuity of human occupation in the region since the Middle Pleistocene. Very little research has been conducted on the foraging potential of carbohydrate resources in the CFR. This study focuses on the seasonal availability of plants with edible carbohydrates at six-weekly intervals over a two-year period in four vegetation types on South Africa’s Cape south coast. Different plant species were considered available to foragers if the edible carbohydrate was directly (i.e. above-ground edible portions) or indirectly (above-ground indications to below-ground edible portions) visible to an expert botanist familiar with this landscape. A total of 52 edible plant species were recorded across all vegetation types. Of these, 33 species were geophytes with edible USOs and 21 species had aboveground edible carbohydrates. Limestone Fynbos had the richest flora, followed by Strandveld, Renosterveld and lastly, Sand Fynbos. The availability of plant species differed across vegetation types and between survey years. The number of available USO species was highest for a six-month period from winter to early summer (Jul–Dec) across all vegetation types. Months of lowest species’ availability were in mid-summer to early autumn (Jan–Apr); the early winter (May–Jun) values were variable, being highest in Limestone Fynbos. However, even during the late summer carbohydrate “crunch,” 25 carbohydrate bearing species were visible across the four vegetation types. To establish a robust resource landscape will require additional spatial mapping of plant species abundances. Nonetheless, our results demonstrate that plant-based carbohydrate resources available to Stone Age foragers of the Cape south coast, especially USOs belonging to the Iridaceae family, are likely to have comprised a reliable and nutritious source of calories over most of the year.
Proteins persist longer in the fossil record than DNA, but the longevity, survival mechanisms and substrates remain contested. Here, we demonstrate the role of mineral binding in preserving the protein sequence in ostrich (Struthionidae) eggshell, including from the palaeontological sites of Laetoli (3.8 Ma) and Olduvai Gorge (1.3 Ma) in Tanzania. By tracking protein diagenesis back in time we find consistent patterns of preservation, demonstrating authenticity of the surviving sequences. Molecular dynamics simulations of struthiocalcin-1 and -2, the dominant proteins within the eggshell, reveal that distinct domains bind to the mineral surface. It is the domain with the strongest calculated binding energy to the calcite surface that is selectively preserved. Thermal age calculations demonstrate that the Laetoli and Olduvai peptides are 50 times older than any previously authenticated sequence (equivalent to ~16 Ma at a constant 10°C).
There are multiple hypotheses for human responses to glacial cycling in the Late Pleistocene, including changes in population size, interconnectedness, and mobility. Lithic technological analysis informs us of human responses to environmental change because lithic assemblage characteristics are a reflection of raw material transport, reduction, and discard behaviors that depend on hunter-gatherer social and economic decisions. Pinnacle Point Site 5–6 (PP5-6), Western Cape, South Africa is an ideal locality for examining the influence of glacial cycling on early modern human behaviors because it preserves a long sequence spanning marine isotope stages (MIS) 5, 4, and 3 and is associated with robust records of paleoenvironmental change.
The analysis presented here addresses the question, what, if any, lithic assemblage traits at PP5-6 represent changing behavioral responses to the MIS 5-4-3 interglacial-glacial cycle? It statistically evaluates changes in 93 traits with no a priori assumptions about which traits may significantly associate with MIS. In contrast to other studies that claim that there is little relationship between broad-scale patterns of climate change and lithic technology, we identified the following characteristics that are associated with MIS 4: increased use of quartz, increased evidence for outcrop sources of quartzite and silcrete, increased evidence for earlier stages of reduction in silcrete, evidence for increased flaking efficiency in all raw material types, and changes in tool types and function for silcrete. Based on these results, we suggest that foragers responded to MIS 4 glacial environmental conditions at PP5-6 with increased population or group sizes, ‘place provisioning’, longer and/or more intense site occupations, and decreased residential mobility. Several other traits, including silcrete frequency, do not exhibit an association with MIS. Backed pieces, once they appear in the PP5-6 record during MIS 4, persist through MIS 3. Changing paleoenvironments explain some, but not all temporal technological variability at PP5-6.
The systematic exploitation of marine foods by terrestrial mammals lacking aquatic morphologies is rare. Widespread ethnographic and archaeological evidence from many areas of the world shows that modern humans living on coastlines often ratchet up the use of marine foods and develop social and technological characteristics unusual to hunter-gatherers and more consistent with small scale food producing societies. Consistent use of marine resources often is associated with reduced mobility, larger group size, population packing, smaller territories, complex technologies, increased economic and social differentiation, and more intense and wide-ranging gifting and exchange. The commitment to temporally and spatially predictable and dense coastal foods stimulates investment in boundary defense resulting in inter-group conflict as predicted by theory and documented by ethnography. Inter-group conflict provides an ideal context for the proliferation of intra-group cooperative behaviors beneficial to the group but not to the altruist (Bowles, 2009). The origins of this coastal adaptation marks a transformative point for the hominin lineage in Africa since all previous adaptive systems were likely characterized by highly mobile, low-density, egalitarian populations with large territories and little boundary defense. It is important to separate occasional uses of marine foods, present among several primate species, from systematic and committed coastal adaptations. This paper provides a critical review of where and when systematic use of coastal resources and coastal adaptations appeared in the Old World by a comparison of the records from Africa and Europe. It is found that during the Middle Stone Age in South Africa there is evidence that true coastal adaptations developed while there is, so far, a lack of evidence for even the lowest levels of systematic coastal resource use by Neanderthals in Europe. Differences in preservation, sample size, and productivity between these regions do not explain the pattern.