Middle and Later Stone Age large mammal and tortoise remains from Die Kelders Cave 1, Western Cape Province, South Africa

Maternal Relationships among Ancient and Modern Southern African Sheep: Newly Discovered Mitochondrial Haplogroups

Simple Summary

The genetic diversity of southern African sheep remains under-studied. We present here the complete mitochondrial genomes of archaeological southern African sheep, as well as the genomes from three indigenous southern African breeds—Damara, Namaqua Afrikaner, and Ronderib Afrikaner. We show that southern African sheep exhibit limited genetic diversity which is consistent with our understanding of their migration south from northernmost Africa. Intriguingly, many of the modern sheep show close relationships with the archaeological sheep, implying an ancestor-descendant relationship. Similarly, the sheep that do not exhibit a close relationship with the archaeological sheep nonetheless cluster closely with each other and do not show a close relationship with European and Asian sheep. This suggests that they too are descendants of indigenous sheep and not the product of historic introductions of exotic breeds.

Abstract

We investigated the genetic diversity and historic relationships among southern African sheep as well as the relationships between them and sheep outside the continent by sourcing both archaeological and modern sheep samples. Archaeological sheep samples derived from the site Die Kelders 1, near Cape Town, date to approximately 1500 years ago. The modern samples were taken as ear snips from Damara, Namaqua Afrikaner, and Ronderib Afrikaner sheep on a farm in Prieska in the Northern Cape. Illumina sequencing libraries were constructed for both ancient and modern specimens. Ancient specimens were enriched for the mitochondrial genome using an in-solution hybridization protocol and modern specimens were subjected to shotgun sequencing. Sequences were mapped to the Ovis aries reference genome, assigned to haplogroups and subhaplogroups, and used to calculate a phylogenetic tree using previously published, geographically dispersed mitochondrial genome sheep sequences. Genetic diversity statistics show that southern African sheep have lower diversity than sheep in other regions. Phylogenetic analysis reveals that many modern southern African sheep are likely descended from prehistoric indigenous sheep populations and not from sheep imported from Europe during the historic period.

High diversity, inbreeding and a dynamic Pleistocene demographic history revealed by African buffalo genomes

Genomes retain records of demographic changes and evolutionary forces that shape species and populations. Remnant populations of African buffalo (Syncerus caffer) in South Africa, with varied histories, provide an opportunity to investigate signatures left in their genomes by past events, both recent and ancient. Here, we produce 40 low coverage (7.14×) genome sequences of Cape buffalo (S. c. caffer) from four protected areas in South Africa. Genome-wide heterozygosity was the highest for any mammal for which these data are available, while differences in individual inbreeding coefficients reflected the severity of historical bottlenecks and current census sizes in each population. PSMC analysis revealed multiple changes in N_e between approximately one million and 20 thousand years ago, corresponding to paleoclimatic changes and Cape buffalo colonisation of southern Africa. The results of this study have implications for buffalo management and conservation, particularly in the context of the predicted increase in aridity and temperature in southern Africa over the next century as a result of climate change.

Systematic Ancient DNA Species Identification Fails to Find Late Holocene Domesticated Cattle in Southern Africa

Establishing robust temporal control of the arrival of domesticated stock and the associated husbandry skills and lifeways in Southern Africa remains frustrated by the osteological similarities between domestic stock and wild endemic fauna. We report the results of a systematic ancient DNA survey of appropriately sized bovid remains from Later Stone Age deposits in four South African archaeological sites. We show that none of the tested remains originated in domesticated cattle. The precise date of arrival of domestic cattle in the region awaits further study, although we also report new radiocarbon determinations which further refine the local chronology.

New Experiments and a Model-Driven Approach for Interpreting Middle Stone Age Lithic Point Function Using the Edge Damage Distribution Method

The Middle Stone Age (MSA) is associated with early evidence for symbolic material culture and complex technological innovations. However, one of the most visible aspects of MSA technologies are unretouched triangular stone points that appear in the archaeological record as early as 500,000 years ago in Africa and persist throughout the MSA. How these tools were being used and discarded across a changing Pleistocene landscape can provide insight into how MSA populations prioritized technological and foraging decisions. Creating inferential links between experimental and archaeological tool use helps to establish prehistoric tool function, but is complicated by the overlaying of post-depositional damage onto behaviorally worn tools. Taphonomic damage patterning can provide insight into site formation history, but may preclude behavioral interpretations of tool function. Here, multiple experimental processes that form edge damage on unretouched lithic points from taphonomic and behavioral processes are presented. These provide experimental distributions of wear on tool edges from known processes that are then quantitatively compared to the archaeological patterning of stone point edge damage from three MSA lithic assemblages-Kathu Pan 1, Pinnacle Point Cave 13B, and Die Kelders Cave 1. By using a model-fitting approach, the results presented here provide evidence for variable MSA behavioral strategies of stone point utilization on the landscape consistent with armature tips at KP1, and cutting tools at PP13B and DK1, as well as damage contributions from post-depositional sources across assemblages. This study provides a method with which landscape-scale questions of early modern human tool-use and site-use can be addressed.

The origins and significance of coastal resource use in Africa and Western Eurasia

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.

Taphonomic and paleoecological change in the large mammal sequence from Boomplaas Cave, western Cape, South Africa

Excavations conducted by H.J. Deacon in the 1970s at Boomplaas Cave (BPA) uncovered a stratified sequence of Middle Stone Age (MSA) and Later Stone Age (LSA) deposits spanning the last >65,000 years. This study provides the first comprehensive and integrated taphonomic and paleoecological analysis of the BPA large mammals, with a focus on its implications for understanding human adaptations and environmental changes in southern Africa's Cape Floristic Region (CFR), an area that features prominently in understanding modern human origins. Taphonomic data indicate a complex history of human, carnivore, and raptor accumulation of the large mammal assemblage. The anthropogenic signal is largely absent from the bottom of the sequence (>65,000 years ago), intermediate in MSA and LSA assemblages from ~50,000 to 20,000 years ago, and strong in LSA deposits post-dating the Last Glacial Maximum (LGM). When viewed in the broader CFR context, the inferred occupation history of BPA is consistent with the hypothesis that both MSA and LSA human populations were concentrated on the submerged coastline from ~60,000 to ~20,000 years ago. Intensive occupation following the LGM parallels an apparent increase in regional population densities, which may have been driven in part by rising sea levels. The BPA ungulate assemblage is characterized by the rise and decline of a taxonomically diverse grazing community, which peaks during the LGM. These changes are not correlated with taphonomic shifts, meaning that they are likely driven by environmental factors, namely the expansion and contraction of grassland habitats. Changes in ungulate diversity indicate that effective precipitation was highest during the LGM, corresponding with an intensified winter rainfall system. This is consistent with recent arguments that the LGM in this region may not have been extremely harsh and arid.

Taphonomic analysis of the Middle Stone Age larger mammal faunal assemblage from Blombos Cave, southern Cape, South Africa

A detailed taphonomic analysis is reported for a sample of the larger mammalian faunal assemblage (>4.5 kg live body weight) from Blombos Cave. The analysis provides an assessment of human involvement in the accumulation and modification of the faunal assemblage, and precedes equally detailed analyses and separate reports of Middle Stone Age (MSA) butchery, transport, and hunting behaviour. At Blombos, there are clear differences in the relative abundances of ungulate body size classes, with the lower MSA phases (upper/lower M2 and M3) showing a high representation of size 1 ungulates relative to the most recent MSA phase (M1). The bones from the earliest MSA phase (M3) have not undergone much post-depositional fragmentation, in contrast to fragments from more recent phases (M1 and upper M2). Much of this variability can be attributed to more burning activity and trampling during M1 and upper M2, which could indicate more intensive occupation. Bone surfaces are variably preserved, with high levels of exfoliation in the most recent two phases. Surface modification analyses revealed high proportions of human modification throughout the sequence, indicating that MSA humans were responsible for accumulating most of the larger mammals. After discard, the bones were modified by scavenging carnivores, leading to a moderate amount of density-mediated destruction and tooth-marking. Carnivores independently accumulated some of the smaller ungulates, mainly in the form of partially-digested remains. Raptorial birds are not implicated as major faunal accumulators. The results from Blombos are directly comparable with analogous datasets from two other sites in the Western Cape (Pinnacle Point Cave 13B and Die Kelders Cave 1). Such comparisons demonstrate that MSA faunal assemblages from nearby coastal sites have complex and different taphonomic histories both within and between sites. Because the human occupants were a major part of these processes, MSA subsistence behaviour and site use was also quite variable over time and space.

Middle and late Pleistocene faunas of Pinnacle Point and their paleoecological implications

The Western Cape region of South Africa is home to a unique type of mediterranean vegetation called fynbos, as well as some of the earliest sites of modern human occupation in southern Africa. Reconstructing the paleohabitats during occupations of these early anatomically modern Homo sapiens is important for understanding the availability of resources to the humans during the development of behaviors that are often considered advanced. These reconstructions are critical to understanding the nature of the changes in the environment and resources over time. Here we analyze the craniodental fossils of the larger mammals recovered from two Pleistocene assemblages in the Pinnacle Point complex, Mossel Bay, Western Cape Region, South Africa. We reconstruct the paleohabitats as revealed by multivariate analyses of the mammalian community structures. Pinnacle Point 30 is a carnivore assemblage and Pinnacle Point 13B includes early evidence of a suite of modern human behavior; together they present an opportunity to identify environmental change over time at a localized geographic scale. Further, this is the first such study to include dated Western Cape localities from Marine Isotope Stage 6, a time of environmental pressure that may have marginalized human populations. Results indicate that environmental change in the Western Cape was more complex than generalized C(4) grassland expansions replacing fynbos habitats during glacial lowered sea levels, and thus, resources available to early modern humans in the region may not have been entirely predictable.

Glacial cycling, large mammal community composition, and trophic adaptations in the Western Cape, South Africa

Some of the earliest evidence for modern human behavior has been recovered from the Western Cape Province, South Africa. Archaeological and paleontological sites in the Western Cape are typically described as "glacial" or "interglacial" in aspect based on the numbers of grazers found in the faunal assemblage, as glacial periods are often thought to have been characterized by spreading C(4) grasslands that replaced endemic C(3) shrubland vegetation found in the Western Cape today. Here, we test the hypothesis that glacial and interglacial time periods were associated with a predictable change in large mammal trophic adaptations by analyzing the proportions of grazing larger mammals from 118 levels of 15 Western Cape fossil assemblages sampling marine isotope stage (MIS) 6 to the present time to determine whether there is a change in composition in these communities that might reflect a shift in ecology and habitat. Our results indicate that trophic proportions did not significantly change over time in the Western Cape as a whole, and thus the hypothesis for habitat changes affecting the subsistence ecology of modern humans during the development of modern behavior is not supported. However, our results show that the southwestern subregion of the Western Cape was characterized by the presence of more grazing species through time than the western subregion. Thus, if ecological and population isolation during glacial periods were integral to catalyzing the development of modern behaviors in the Western Cape region of South Africa, then a complex model including the development of possible mosaic habitats is needed.

Eland, buffalo, and wild pigs: were Middle Stone Age humans ineffective hunters?

Patterns of faunal exploitation play a central role in debates concerning the behavioral modernity of Middle Stone Age (MSA) peoples. MSA foragers have been portrayed as less effective hunters than their Later Stone Age (LSA) successors on the basis of relative species abundances from ungulate assemblages in southern Africa. Specifically, MSA hunters are said to focus on docile eland while avoiding more aggressive prey, particularly buffalo and wild pigs. To evaluate these arguments and compare subsistence behavior, I present a quantitative examination of 51 MSA and 98 LSA ungulate assemblages from southern Africa to show that: (1) with respect to ungulate exploitation, MSA diet breadth may have exceeded LSA diet breadth, (2) ungulate assemblage evenness is equivalent in the MSA and LSA, (3) eland, buffalo, and wild pig are equally abundant in the MSA and LSA, and (4) large ungulate prey are more common in the MSA than in the LSA. With few exceptions, the broad patterns, which sample a range of geographic and environmental contexts, are supported by an environmentally controlled comparison of Middle and Later Stone Age faunas that accumulated under interglacial conditions along the southern African coastline. When interpreted within a foraging theory framework, these differences suggest that MSA hunters enjoyed increased meat yields due to elevated encounter rates with large prey. These results need not imply cognitive differences, but are consistent with an increase in human populations from the Middle to Later Stone Age, which resulted in diminished abundances of large ungulates.

Animal exploitation strategies during the South African Middle Stone Age: Howiesons Poort and post-Howiesons Poort fauna from Sibudu Cave

As one of the few sites that preserve fauna from the Howiesons Poort (HP) and the immediately post-HP Middle Stone Age (MSA), Sibudu Cave provides a unique opportunity to explore the range of variability in subsistence behaviors during this important phase in human behavioral evolution. In addition to providing information on subsistence, the faunal assemblage serves as a means of reconstructing the environmental conditions during these two periods. While the HP fauna is dominated by species that prefer closed (particularly forested) habitats, the fauna from the upper-most layers of the post-HP MSA are largely representative of open conditions. These results largely coincide with macrobotanical analyses and may simply indicate that the extent of the riverine forest near the site was greater during the HP. Alternatively, the pattern could be indicative of a marked intensification in the exploitation of the environment in the immediate vicinity of the shelter during the HP, perhaps resulting from a decline in the productivity of adjacent regions. We also document variation in the frequency of the different bovid size classes over time. The evidence shows a declining focus on the smallest bovids after the HP, with a parallel increase in the frequency of large and very large bovids. Beyond a heavy focus on small bovids, small mammals and suids also occur at higher frequencies during the HP. Although the HP faunal assemblage is largely unique as compared to the bulk of the MSA sequence at Sibudu, the evidence presented here suggests that the transition between the HP and the post-HP MSA may have been more gradual than abrupt. Our results indicate that the HP and post-HP MSA inhabitants of Sibudu Cave were capable hunters; however, hunting strategies appear to show marked variation over time. We propose that the variability in animal procurement strategies reflects a degree of behavioral plasticity beyond that generally attributed to MSA populations.

Modern hunting behavior in the early Middle Paleolithic: Faunal remains from Misliya Cave, Mount Carmel, Israel

Understanding the behavioral adaptations and subsistence strategies of Middle Paleolithic humans is critical in the debate over the evolution and manifestations of modern human behavior. The study of faunal remains plays a central role in this context. Until now, the majority of Levantine archaeofaunal evidence was derived from late Middle Paleolithic sites. The discovery of faunal remains from Misliya Cave, Mount Carmel, Israel (>200 ka), allowed for detailed taphonomic and zooarchaeological analyses of these early Middle Paleolithic remains. The Misliya Cave faunal assemblage is overwhelmingly dominated by ungulate taxa. The most common prey species is the Mesopotamian fallow deer (Dama mesopotamica), followed closely by the mountain gazelle (Gazella gazella). Some aurochs (Bos primigenius) remains are also present. Small-game species are rare. The fallow deer mortality pattern is dominated by prime-aged individuals. A multivariate taphonomic analysis demonstrates (1) that the assemblage was created solely by humans occupying the cave and was primarily modified by their food-processing activities; and (2) that gazelle carcasses were transported complete to the site, while fallow deer carcasses underwent some field butchery. The new zooarchaeological data from Misliya Cave, particularly the abundance of meat-bearing limb bones displaying filleting cut marks and the acquisition of prime-age prey, demonstrate that early Middle Paleolithic people possessed developed hunting capabilities. Thus, modern large-game hunting, carcass transport, and meat-processing behaviors were already established in the Levant in the early Middle Paleolithic, more than 200 ka ago.

The mammalian fauna associated with an archaic hominin skullcap and later Acheulean artifacts at Elandsfontein, Western Cape Province, South Africa

The Elandsfontein site, Western Cape Province, South Africa, is well known for an archaic hominin skullcap associated with later Acheulean artifacts. The site has also provided nearly 13,000 mammalian bones that can be identified to skeletal part and taxon. The assemblage derives from 49 species, 15 of which have no historic descendants. Comparisons to radiometrically dated faunas in eastern Africa indicate an age between 1 million and 600 thousand years ago. Unique features of the fauna, including the late occurrence of a dirk-toothed cat and a sivathere, may reflect its geographic origin in a region that was notable historically for its distinctive climate and high degree of biotic endemism. Together, taxonomic composition, geomorphic setting, and pollen extracted from coprolites indicate the proximity of a large marsh or pond, maintained by a higher water table. The small average size of the black-backed jackals implies relatively mild temperatures. The sum of the evidence places bone accumulation during one of the mid-Pleistocene interglacials that were longer and cooler than later ones, including the Holocene. The geomorphic context of the fauna presents no evidence for catastrophe, and most deaths probably resulted from attritional factors that disproportionately killed the young and old. However, only the dental-age profile of long-horned buffalo supports this directly. Field collection methods biased skeletal-part representation, but originally, it probably resembled the pattern in the younger, marsh-edge Acheulean occurrence at Duinefontein 2, 45 km to the south. Excavation there exposed multiple vertebral spreads, which probably mark carcasses from which hominins or large carnivores removed the meatier elements. Bone damage at both sites suggests that, despite abundant artifacts, hominins were much less important than carnivores in the bone accumulation. Together with limited observations from other sites, Elandsfontein and Duinefontein provisionally suggest that Acheulean-age hominins obtained few large mammals, whether by hunting or scavenging.

Primate remains from African crowned eagle (Stephanoaetus coronatus) nests in Ivory Coast's Tai Forest: Implications for primate predation and early hominid taphonomy in South Africa

Understanding the initial processes of deposition can help with interpretations of fossil assemblages. Here we discuss the taphonomy of primate remains collected under 16 nests of African crowned eagles (Stephanoaetus coronatus) in the Tai Forest, Ivory Coast. From 1,200 bones collected, including 669 primate bones, we calculated minimum number of individuals (MNI), survivability profiles, and damage profiles using methods identical to those employed by Sanders et al. (2003 J. Hum. Evol. 44:87-105) in their analysis of bones from eagle nests in Uganda. Crowned eagles leave a consistent taphonomic signature on their prey remains; hence, results from our analysis of the Tai assemblage are similar to those from the Ugandan sample. Hindlimb and cranial bones are relatively abundant in the sample, while ribs, vertebrae, carpals, and tarsals do not survive well. Primate crania typically display puncture marks around the eye, long bones remain largely intact, and scapulae exhibit raked breakage. These data have implications for understanding the dynamic between extant primates and one of their principle predators, as well as the taphonomy of hominid-bearing caves in South Africa. We concur with Berger and Clarke (1995 J. Hum. Evol. 29:275-299) that a large raptor could have been responsible for the death of the Taung child, Australopithecus africanus.

Biogeography and evolution of the genus Homo

The debate about the origins of modern humans has traditionally focussed on two contrasting views. Multi-regional evolution proposes that present-day populations worldwide are the descendants of in situ evolution after an initial dispersal of Homo erectus from Africa during the Lower Pleistocene. The alternative, Out-of-Africa 2, proposes that all present-day populations are descended from a recent common ancestor that lived in East Africa approximately 150 000 years ago, the population of which replaced all regional populations. The weight of the evidence is now in favour of Out-of-Africa 2, and discussion is now dominated by the causes of the dispersal of modern humans out of Africa and the outcome of contact with other populations. Fresh approaches, from disciplines hitherto peripheral to the debate, such as evolutionary ecology, and new discoveries are challenging established views, particularly the prevalent idea that biologically superior modern humans were the cause of the demise of all other populations of Homo worldwide. Climate-driven ecological change has been, as with many other taxa, the driving force in the geographical range dynamics of the genus Homo.

The revolution that wasn't: a new interpretation of the origin of modern human behavior

Proponents of the model known as the "human revolution" claim that modern human behaviors arose suddenly, and nearly simultaneously, throughout the Old World ca. 40-50 ka. This fundamental behavioral shift is purported to signal a cognitive advance, a possible reorganization of the brain, and the origin of language. Because the earliest modern human fossils, Homo sapiens sensu stricto, are found in Africa and the adjacent region of the Levant at >100 ka, the "human revolution" model creates a time lag between the appearance of anatomical modernity and perceived behavioral modernity, and creates the impression that the earliest modern Africans were behaviorally primitive. This view of events stems from a profound Eurocentric bias and a failure to appreciate the depth and breadth of the African archaeological record. In fact, many of the components of the "human revolution" claimed to appear at 40-50 ka are found in the African Middle Stone Age tens of thousands of years earlier. These features include blade and microlithic technology, bone tools, increased geographic range, specialized hunting, the use of aquatic resources, long distance trade, systematic processing and use of pigment, and art and decoration. These items do not occur suddenly together as predicted by the "human revolution" model, but at sites that are widely separated in space and time. This suggests a gradual assembling of the package of modern human behaviors in Africa, and its later export to other regions of the Old World. The African Middle and early Late Pleistocene hominid fossil record is fairly continuous and in it can be recognized a number of probably distinct species that provide plausible ancestors for H. sapiens. The appearance of Middle Stone Age technology and the first signs of modern behavior coincide with the appearance of fossils that have been attributed to H. helmei, suggesting the behavior of H. helmei is distinct from that of earlier hominid species and quite similar to that of modern people. If on anatomical and behavioral grounds H. helmei is sunk into H. sapiens, the origin of our species is linked with the appearance of Middle Stone Age technology at 250-300 ka.

Middle Stone Age stratigraphy and excavations at Die Kelders Cave 1 (Western Cape Province, South Africa): the 1992, 1993, and 1995 field seasons

Die Kelders Cave 1, first excavated under the direction of Franz Schweitzer in 1969-1973, was re-excavated between 1992 and 1995 by a combined team from the South African Museum, SUNY at Stony Brook, and Stanford University. These renewed excavations enlarged the artefactual and faunal samples from the inadequately sampled and less intensively excavated lower Middle Stone Age (MSA) layers, increased our understanding of the complex site formation processes within the cave, enlarged the hominid sample from the MSA deposits, and generated ESR, TL, and OSL dates for the MSA layers. Importantly, these new excavations dramatically improved our comprehension of the vertical and lateral characteristics of the MSA stratigraphy. Surface plotting of the MSA layers has led to the identification of at least two major zones of subsidence that significantly warped the layers, draping some along the eroding surface contours of major blocks of fallen limestone roof rock. A third zone of subsidence is probably present in the older excavations. Dramatic roof falls of very large limestone blocks occurred at least twice-once in the middle of Layer 4/5 where the roof blocks were only slightly weathered after collapse, and at the top of Layer 6 where the blocks weathered heavily after collapse, producing a zone of decomposed rock around the blocks. Many of the sandy strata are cut by small and localized faults and slippages. All of the strata documented by Schweitzer's excavations are present throughout the exposed area to the west of his excavated area, where many of them thicken and become more complex. Layer 6, the thickest MSA layer, becomes less diagenetically altered and compressed to the west.

Zooarchaeological and taphonomic analysis of the Die Kelders Cave 1 layers 10 and 11 Middle Stone Age larger mammal fauna

Middle Stone Age (MSA) and Middle Paleolithic (MP) faunal assemblages have gained widespread attention due to their relevance to the debate over the modernity of hominid behavior during the MSA/MP. A recent critique of the scavenging argument for MSA/MP behavior drew on a summary presentation of the skeletal abundance and surface modification data from Die Kelders Cave 1 Layer 10 (Marean, 1998). This paper provides a more complete presentation of those data, adds the smaller Layer 11 sample, and provides a detailed analysis of the taphonomic history of both samples.Bone fragment density is higher in Layer 10 than in Layer 11. Bone densities vary horizontally as well, with Layer 10 showing greater deposition in the exposed areas of the cave. An analysis of long bone breakage patterns indicates that non-nutritive breakage on the Layers 10 and 11 samples was present but not intense. Size 1 mammals were predominantly accumulated by owls and/or other large raptors, not hominids, in Layer 10. Hominids were the predominant accumulator of Sizes 2-4 mammals in Layers 10 and 11 as indicated by the frequency of hammer-stone percussion marks and carnivore toothmarks. After discard by hominids, a significant portion of these remains were discovered and scavenged by carnivores. Overall, the larger mammal fauna of Layer 10 is dominated by Sizes 3 and 4 bovids, mostly young and adult eland, and thus hominids were focusing on the high-ranked prey items. Shaft portions of long bones, the portions with the most flesh, have the highest frequencies of cutmarks. A comparison of the Layers 10 and 11 cutmark frequencies to Selvaggio's (1998) scavenging model shows that the frequencies are significantly outside the range of variation documented in Selavaggio's scavenging sample.