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Evaluating the potential for tactical hunting in the Middle Stone Age: Insights from a bonebed of the extinct bovid, Rusingoryx atopocranion
Abstract
The foraging behaviors of Middle Stone Age (MSA) early modern humans have largely been based on evidence from well-stratified cave sites in South Africa. Whereas these sites have provided an abundance of data for behavioral reconstruction that are unmatched elsewhere in Africa, they are unlikely to preserve evidence of the diversity of foraging strategies employed by MSA hunters who lived in a variety of ecological and landscape settings across the African continent. Here we describe the results of recent excavations at the open-air site of Bovid Hill at Wakondo, Rusinga Island, Kenya, which yielded 24 in situ MSA artifacts within an assemblage of bones comprised exclusively of the extinct alcelaphin bovid Rusingoryx atopocranion. The excavated faunal assemblage is characterized by a prime-age-dominated mortality profile and includes cut-marked specimens and an associated MSA Levallois blade-based artifact industry recovered from a channel deposit dated to 68 ± 5 ka by optically stimulated lumines-cence. Taphonomic, geologic, and faunal evidence points to mass exploitation of Rusingoryx by humans at Bovid Hill, which likely represents an initial processing site that was altered post-depositionally by fluvial processes. This site highlights the importance of rivers and streams for mass procurement in an open and seasonal landscape, and provides important new insights into MSA behavioral variability with respect to environmental conditions, site function, and tactical foraging strategies in eastern Africa. Bovid Hill thus joins a growing number of MSA and Middle Paleolithic localities that are suggestive of tactical hunting behaviors and mass capture of gregarious ungulate prey.
... The late Pleistocene large mammal communities were composed of numerous extinct taxa, some of which were dominant members of the region's faunas until the onset of the Holocene (MacInnes, 1956;Marean and Gifford-Gonzalez, 1991;Marean, 1992;Faith et al., 2015;Lesur et al., 2016;Tryon et al., 2016). This emerging perspective has been reinforced by ongoing research in the Kenyan portions of the Lake Victoria Basin since 2008, which has documented numerous extinct taxa (Rusingoryx atopocranion, Damaliscus hypsodon, Kolpochoerus, and others) in late Pleistocene sediments, including new species or those formerly thought to have disappeared from eastern Africa during the middle Pleistocene (e.g., Tryon et al., 2010Tryon et al., , 2012Tryon et al., , 2016Faith et al., 2011Faith et al., , 2014Faith et al., , 2015Jenkins et al., 2017). These new data show that Homo sapiens in eastern Africa evolved among nonanalog faunal communities (e.g., Faith et al., 2016), as has long been recognized for southern Africa (e.g., Klein, 1980). ...
... Sites with large assemblages of reliably associated postcranial remains or taxa with diagnostic features in many postcranial elements are rare. An important exception is the Bovid Hill archaeological site at Wakondo on Rusinga Island within Lake Victoria ( Fig. 1) (see also Marean, 1990Marean, , 1992Marean, , 1997, which preserves a large, monospecific bonebed that resulted from the targeted hunting of a herd of the extinct bovid R. atopocranion (Jenkins et al., 2017). ...
... The Bovid Hill assemblage thus affords a rare opportunity to provide a more holistic understanding of its ecology. In addition to the bonebed accumulation at Bovid Hill, remains of the alcelaphin bovid Rusingoryx have been recovered from other late Pleistocene sediments (∼100-36 ka) around the Kenyan Lake Victoria Basin, including both Rusinga and Mfangano islands and mainland sites Luanda West and Karungu (Faith et al., 2011;O'Brien et al., 2016;Tryon et al., 2016;Blegen et al., 2017;Jenkins et al., 2017). ...
Rusingoryx atopocranion is an extinct alcelaphin bovid from the late Pleistocene of Kenya, known for its distinctive hollow nasal crest. A bonebed of R. atopocranion from the Lake Victoria Basin provides a unique opportunity to examine the nearly complete postcranial ecomorphology of an extinct species, and yields data that are important to studying paleoenvironments and human-environment interaction. With a comparative sample of extant African bovids, we used discriminant function analyses to develop statistical ecomorphological models for 18 skeletal elements and element portions. Forelimb and hin-dlimb element models overwhelmingly predict that R. atopocranion was an open-adapted taxon. However, the phalanges of Rusingoryx are remarkably short relative to their breadth, a morphology outside the range of extant African bovids, which we interpret as an extreme open-habitat adaptation. It follows that even recently extinct fossil bovids can differ in important morphological ways relative to their extant counterparts, particularly if they have novel adaptations for past environments. This unusual phalanx morphology (in combination with other skeletal indications), mesowear, and dental enamel stable isotopes, demonstrate that Rusingoryx was a grassland specialist. Together, these data are consistent with independent geological and paleontological evidence for increased aridity and expanded grassland habitats across the Lake Victoria Basin.
... Geologic and tephrostratigraphic research around the region has demonstrated that deposits correlative to the Wasiriya Beds exist across several hundred square kilometers on Mfangano Island and along the eastern shore of Lake Victoria Faith et al., 2015;Blegen et al., 2015Blegen et al., , 2017. This research on Rusinga Island and the surrounding region has added many new details to our understanding of the geology, archaeology, and fossil assemblages of the region, which has allowed for studies of the archaeological and paleoecological change during the Late Pleistocene (Tryon et al., 2010Faith et al., 2011Faith et al., , 2014Faith et al., , 2015Garrett et al., 2015;Van Plantinga, 2011;Beverly et al., 2015aBeverly et al., , b, 2017Blegen et al., 2015Blegen et al., , 2017Jenkins et al., 2017). ...
... The fauna from Nyamita is dominated by semiarid grassland taxa (Table 1) including five extinct taxa, Rusingoryx atopocranion (Faith et al., 2011;O'Brien et al., 2016), a herd of which has been recovered 2 km away from the~68 ka bone bed at Bovid Hill, Wakondo (Jenkins et al., 2017), giant wildebeest (Megalotragus sp.), the exceptionally hypsodont, blesbok-like Damaliscus hypsodon , a distinctive, highly hypsodont impala , and the aardvark Orycteropus crassidens (MacInnes, 1956). The presence of hippopotamuses and two species of reedbuck (Redunca redunca and Redunca cf. ...
... The surface of the bone is essentially unweathered, but has a few hints of longitudinal crack developing on the anterior side of the shaft (i.e., between Behrensmeyer's weathering stages 0 and 1; Behrensmeyer, 1978;Lyman, 1994), suggesting that the humerus was buried rapidly. This observation is consistent with the other fauna from the Wasiriya Beds, which are generally very minimally weathered (e.g., Jenkins et al., 2017;Blegen et al., 2017). The ragged proximal end, including an oblique fracture on the lateral cortex, likely reflects carnivore gnawing of fresh bone, whereas the perpendicular fracture marking the distal end indicates dry-bone breakage. ...
In 2010, a hominin right humerus fragment (KNM-RU 58330) was surface collected in a small gully at Nyamita North in the Late Pleistocene Wasiriya Beds of Rusinga Island, Kenya. A combination of stratigraphic and geochronological evidence suggests the specimen is likely between ∼49 and 36 ka in age. The associated fauna is diverse and dominated by semiarid grassland taxa. The small sample of associated Middle Stone Age artifacts includes Levallois flakes, cores, and retouched points. The 139 mm humeral fragment preserves the shaft from distal to the lesser tubercle to 14 mm below the distal end of the weakly projecting deltoid tuberosity. Key morphological features include a narrow and weakly marked pectoralis major insertion and a distinctive medial bend in the diaphysis at the deltoid insertion. This bend is unusual among recent human humeri but occurs in a few Late Pleistocene humeri. The dimensions of the distal end of the fragment predict a length of 317.9 ± 16.4 mm based on recent samples of African ancestry. A novel method of predicting humeral length from the distance between the middle of the pectoralis major and the bottom of the deltoid insertion predicts a length of 317.3 mm ± 17.6 mm. Cross-sectional geometry at the midshaft shows a relatively high percentage of cortical bone and a moderate degree of flattening of the shaft. The Nyamita humerus is anatomically modern in its morphology and adds to the small sample of hominins from the Late Pleistocene associated with Middle Stone Age artifacts known from East Africa. It may sample a population closely related to the people of the out-of-Africa migration.
... Two excavations have been conducted at Wakondo (Jenkins et al. 2017;Tryon et al. 2010). A 4m 2 trench dug to an average depth of 0.7m recovered nine artifacts in situ (Tryon et al. 2010). ...
... A 4m 2 trench dug to an average depth of 0.7m recovered nine artifacts in situ (Tryon et al. 2010). At Wakondo Bovid Hill, the larger of the two excavations, a series of trenches totaling 19m 2 with an average depth of 0.50m were excavated into small and shallow braided stream channels cutting into a paleosol overlying the Wakondo Tuff (Jenkins et al. 2017;Tryon et al. 2010). These excavations targeted a bone-bed of the extinct alcelaphin Rusingoryx atopocranion deposited in sediments OSL dated to 68 ka . ...
... Stone artifacts from the Bovid Hill excavation are few (n=78 with 9 in situ), but these lithic artifacts are laminar, including those produced by Levallois methods, and are consistent with an MSA attribution. Cut-marked fauna indicates an association between the bones and stone artifacts (Jenkins et al. 2017;Tryon et al. 2010). ...
Here we report tephra correlations, lithic artifacts, obsidian sourcing data, and fauna from nine Late Pleistocene localities of the eastern Lake Victoria basin of western Kenya, as well as new excavations from the 49-36 ka site of Nyamita Main on Rusinga Island. The Late Pleistocene of Africa is an important period for the evolution and dispersals of Homo sapiens. A conspicuous behavioral feature of this period is the replacement of Middle Stone Age (MSA) technologies by Later Stone Age (LSA) technologies. Current research shows this process is complex with the LSA appearing and the MSA disappearing at different times in different places across Africa. Accounting for this pattern requires a precise chronology, detailed evidence of past human behavior and environmental reconstructions of the appropriate scale. Data presented here provide this detail. Tephra correlations improve the regional chronology and expand the lateral area of Late Pleistocene eastern Lake Victoria basin exposures from ~650km 2 to >2500km 2. Lithic artifacts show MSA technology is present younger than 36 ka in western Kenya, 25-35 kyr younger than the first appearance of early LSA technology elsewhere in equatorial East Africa. Obsid-ian sourcing data presented here shows the use of the same raw material sources by MSA and LSA populations through long periods of time from >100 ka through <36 ka. The methods employed here provide the temporal resolution and appropriate geographic scale to address modern human behavioral evolution.
... For comparative purposes, we also include taxonomic abundances (specimen counts) for the Late Pleistocene paleontological assemblages from Karungu and Rusinga Island (data from Faith et al., 2019a), along with Holocene zooarchaeological samples from Wadh Lang'o (Prendergast, 2010) and an aggregate of several Holocene assemblages from the southern shores of the Winam Gulf (Robertshaw et al., 1983). We exclude the Wakondo locality from Rusinga Island because the majority of specimens are derived from a mass death assemblage of the extinct alcelaphin Rusingoryx atopocranion (Jenkins et al., 2018). The fossil data are included in the correspondence analysis as supplementary points (i.e., they are projected in the same multivariate space as the modern assemblages, but have no influence on the ordination of sites or taxa). ...
... The lack of well-preserved horn cores in the Lake Victoria Basin, together with the absence of specimens from the intervening >0.5 Myr, render the latter phase of Megalotragus evolution in eastern Africa unclear. An offshoot of this lineage is represented in the regional Late Pleistocene sequence by the smaller-bodied Rusingoryx atopocranion, currently known only from the eastern Lake Victoria basin O'Brien et al., 2016;Jenkins et al., 2018). ...
We report on the Late Pleistocene (36-12 ka) mammals from Kibogo in the Nyanza Rift of western Kenya, providing (1) a systematic description of the mammal remains, (2) an assessment of their paleoenvironmental implications, and (3) an analysis of the biogeographic implications of non-analog species associations. Kibogo has yielded one of the largest paleontological assemblages from the Late Pleistocene of eastern Africa, and it is dominated by grassland ungulates (e.g., equids and alcelaphin antelopes), including an assortment of extralimital (e.g., Equus grevyi, Ceratotherium simum, Redunca arundinum) and extinct species (Syncerus antiquus, Damaliscus hypsodon, Megalotragus sp.). The composition of the fauna, in conjunction with the soils and topography of the region, indicate the local presence of edaphic grassland situated within a broader environment that was substantially grassier and likely drier than at present. In contrast to non-analog faunas from higher latitudes (e.g., North America and western Eurasia), the climatic niches of non-analog species associations strongly overlap, indicating that non-analog climate regimes during the Late Pleistocene of eastern Africa are not necessary to account for the former association of presently allopatric species. The Kibogo faunas add to a growing body of evidence implying that the composition of present-day African herbivore communities is distinct from those of the geologically recent past.
... The Late Pleistocene geology, fossils, and MSA artifacts from Rusinga and Mfangano Islands have been the focus of research since 2009 (Tryon et al., 2010Faith et al., 2011Faith et al., , 2012Faith et al., , 2014Van Plantinga, 2011;Jenkins et al., 2017;Blegen et al., in press). More recently, this research has expanded to include the deposits around the region known as Karungu ∼40 km to the south near the town of Sori (Figure 1; Beverly et al., 2015a,b;Blegen et al., 2015;Faith et al., 2015). ...
... Locations of in situ fossils and MSA artifacts are indicated in the stratigraphy (Figure 2). Artifacts from excavations at Nyamita and Wakondo on Rusinga Island in particular appear associated with formerly stable land surfaces, including weakly developed paleosols (Jenkins et al., 2017;Blegen et al., in press). Artifact density and the presence of non-local raw material types from excavated areas and surface collections are generally consistent with production by highly mobile populations of foragers (Tryon et al., 2010;Faith et al., 2015;Garrett et al., 2015;Blegen et al., in press). ...
The impact of changing environments on the evolution and dispersal of Homo sapiens is highly debated, but few data are available from equatorial Africa. Lake Victoria is the largest freshwater lake in the tropics and is currently a biogeographic barrier between the eastern and western branches of the East African Rift. The lake has previously desiccated at ~17 ka and again at ~15 ka, but little is known from this region prior to the Last Glacial Maximum. The Pleistocene terrestrial deposits on the northeast coast of Lake Victoria (94–36 ka) are ideal for paleoenvironmental reconstructions where volcaniclastic deposits (tuffs), fluvial deposits, tufa, and paleosols are exposed, which can be used to reconstruct Critical Zones (CZ) of the past (paleo-CZs). The paleo-CZ is a holistic concept that reconstructs the entire landscape using geologic records of the atmosphere, hydrosphere, lithosphere, biosphere, and pedosphere (the focus of this study). New paleosol-based mean annual precipitation (MAP) proxies from Karungu, Rusinga Island, and Mfangano Island indicate an average MAP of 750 ± 108 mm year−1 (CALMAG), 800 ± 182 mm year−1 (CIA-K), and 1,010 ± 228 mm year−1 (PPM1.0) with no statistical difference throughout the 11 m thick sequence. This corresponds to between 54 and 72% of modern precipitation. Tephras bracketing these paleosols have been correlated across seven sites, and sample a regional paleo-CZ across a ~55 km transect along the eastern shoreline of the modern lake. Given the sensitivity of Lake Victoria to precipitation, it is likely that the lake was significantly smaller than modern between 94 and 36 ka. This would have removed a major barrier for the movement of fauna (including early modern humans) and provided a dispersal corridor across the equator and between the rifts. It is also consistent with the associated fossil faunal assemblage indicative of semi-arid grasslands. During the Late Pleistocene, the combined geologic and paleontological evidence suggests a seasonally dry, open grassland environment for the Lake Victoria region that is significantly drier than today, which may have facilitated human and faunal dispersals across equatorial East Africa.
... 86 However, two of the three MSA sites in East Africa with sufficient evidence to reconstruct foraging methods suggest communal foraging did occur. 59 In some dry environments, like those found in southern Africa, large migratory herds of springbok were common until recently and may have been harvested using drivelines. 75 In forest environments, communal net hunting has been widely observed, although limited to groups less than 60 individuals. ...
We present evidence that people in small‐scale mobile hunter‐gatherer societies cooperated in large numbers to produce collective goods. Foragers engaged in large‐scale communal hunts and constructed shared capital facilities; they made shared investments in improving the local environment; and they participated in warfare, formed enduring alliances, and established trading networks. Large‐scale collective action often played a crucial role in subsistence. The provision of public goods involved the cooperation of many individuals, so each person made only a small contribution. This evidence suggests that large‐scale cooperation occurred in the Pleistocene societies that encompass most of human evolutionary history, and therefore it is unlikely that large‐scale cooperation in Holocene food producing societies results from an evolved psychology shaped only in small‐group interactions. Instead, large‐scale human cooperation needs to be explained as an adaptation, likely rooted in distinctive features of human biology, grammatical language, increased cognitive ability, and cumulative cultural adaptation.
... Assessment of prey choice and subsistence economies is not possible without secure taxonomic identifications. Bovid size classes have typically been used to assess broad hunting, transport, and carcass processing strategies [12,15], but as bovids inhabit varying environments and exhibit behavioral differences, narrower identifications reveal more detail about forager decisions and tactics [23,58,62,[70][71][72][73] (Fig 4). Finally, bovid and mammal size classes used by zooarchaeologists across Africa vary [1,58,74], and therefore narrower identifications can aid in inter-regional comparisons of zooarchaeological data. ...
Assessing past foodways, subsistence strategies, and environments depends on the accurate identification of animals in the archaeological record. The high rates of fragmentation and often poor preservation of animal bones at many archaeological sites across sub-Saharan Africa have rendered archaeofaunal specimens unidentifiable beyond broad categories, such as “large mammal” or “medium bovid”. Identification of archaeofaunal specimens through Zooarchaeology by Mass Spectrometry (ZooMS), or peptide mass fingerprinting of bone collagen, offers an avenue for identification of morphologically ambiguous or unidentifiable bone fragments from such assemblages. However, application of ZooMS analysis has been hindered by a lack of complete reference peptide markers for African taxa, particularly bovids. Here we present the complete set of confirmed ZooMS peptide markers for members of all African bovid tribes. We also identify two novel peptide markers that can be used to further distinguish between bovid groups. We demonstrate that nearly all African bovid subfamilies are distinguishable using ZooMS methods, and some differences exist between tribes or sub-tribes, as is the case for Bovina (cattle) vs. Bubalina (African buffalo) within the subfamily Bovinae. We use ZooMS analysis to identify specimens from extremely fragmented faunal assemblages from six Late Holocene archaeological sites in Zambia. ZooMS-based identifications reveal greater taxonomic richness than analyses based solely on morphology, and these new identifications illuminate Iron Age subsistence economies c. 2200–500 cal BP. While the Iron Age in Zambia is associated with the transition from hunting and foraging to the development of farming and herding, our results demonstrate the continued reliance on wild bovids among Iron Age communities in central and southwestern Zambia Iron Age and herding focused primarily on cattle. We also outline further potential applications of ZooMS in African archaeology.
... *mortality data used in the analysis was taken from various sources: lion (Mitchell et al., 1965;Schaller, 1972;Spinage, 1972); leopard (Mitchell et al., 1965);Hyena (Kruuk, 1972); African wild dog (Mitchell et al., 1965;Schaller, 1972); Wolf (Steele, 2004); modern human (Bunn and Gurtov, 2014); Klasies River Mouth (Bunn and Gurtov, 2014); Bovid Hill (Jenkins et al., 2017); Kanjera South (Oliver et al., 2019); FLK Zinj (Oliver et al., 2019). ...
In recent years, the Arabian Peninsula has emerged as a key region for elucidating hominin and faunal evolution and dispersals between Africa and Eurasia. Central to this research is the middle Pleistocene site of Ti's al Ghadah (TAG) which has yielded a diverse and abundant fossil faunal assemblage and the earliest chronometrically dated evidence for hominins in this part of the world. Here, we present the first detailed taphonomic study of the large Unit 5 fossil assemblage from the site. We aim to assess which actor/s were responsible for the accumulation of the assemblage and evaluate evidence that might be consistent with the accumulation of fauna by hominins. We also describe, for the first time, fossils and lithic artefacts from stratigraphic horizons not previously considered, providing taphonomic insights into their accumulation. The taphonomic work shows that the Unit 5 faunal assemblage was accumulated by ambush predators, likely large felids and hominins, in a lake side environment, and that carcasses were subsequently scavenged by more durophagus carnivores such as hyenas and canids. Less can be reliably said regarding the newly described fossil assemblages given their poor preservation and significant wind abrasion, but large carnivores again appear to have played a role, and hominins probably played a role in the accumulation of at least one of these. This study provides the first detail insights into the interplay between hominins, carnivores, and herbivores in Arabia, and suggests that watering holes have been a focus on the Arabian landscape for resources since the middle Pleistocene.
... beisa), and based on water budget models (Broecker et al., 1998;Milly, 1999), implies a massive reduction of Lake Victoria, such that Rusinga and Mfangano islands and Karungu would have represented a contiguous paleo-landscape. The fossil sample from the Wakondo locality on Rusinga Island is not examined here because the majority of specimens are from a mass death assemblage of the extinct alcelaphin bovid Rusingoryx atopocranion (Jenkins et al., 2018). ...
Ecometric analysis involves the examination of quantifiable functional traits across the taxa in a biotic community. Well-documented relationships between certain functional traits and environmental gradients in the present provide the empirical framework for a large body of research that uses ecometrics to reconstruct environments in the fossil record. In current applications of the technique, the taxa present in a fossil assemblage are summarized using the mean value of an environmentally informative trait. This study explores some of the quantitative pitfalls inherent to this approach. Through analysis of dental crown height—a trait that is widely used to infer paleo-precipitation—of Late Pleistocene ungulate assemblages from the Lake Victoria Basin in western Kenya, we illustrate how ecometric means vary as a function of sample size. Sampling artifacts have the potential to bias ecometric means, and the environmental inferences derived from them, whenever there is a non-random distribution of traits across the species abundance distribution (e.g., if abundant taxa have different traits than rare taxa). This sampling issue also means that the degree of analytical precision implied by quantitative paleoenvironmental reconstructions (e.g., annual precipitation at time X was 500 mm/yr) derived from ecometrics may be unwarranted. We recommend that analytical approaches be modified to circumvent these problems and explore three potential solutions: (1) specimen-based rarefaction, (2) coverage-based rarefaction, and (3) weighting ecometric means by taxonomic abundances. Of these, only the latter is robust to variation in sampling effort. Because abundance data are not always available and are potentially unreliable, we outline alternative approaches that could be implemented to contend with sample bias.
... Fluvial transport is one of the most important processes that can affect bones in archaeological sites located close to bodies of water. The frame of reference proposed in Kaufmann et al. (2011), has been applied in various contexts and taxa, helping researchers estimate the role fluvial transport has had in bone accumulation (Jenkins et al., 2017;L opez et al., 2016;Massigoge et al., 2017;Organista et al., 2017;Tomassini et al., 2014;Zunino et al., 2012). Similarly, knowledge of intrataxonomic variability in bone weathering informs researchers of the potential bias in differential bone destruction (Saña et al., 2014). ...
Over the last decade, we have conducted an actualistic taphonomic research program in the Humid Pampas of Argentina, in order to build a corpus of information about the taphonomic agents and processes characterizing this sub-region. In this paper, we present a summary of our results after ten years of actualistic taphonomic studies in the Pampas. Our program includes both naturalistic and experimental research. Some of the controlled experiments consist of studies with different-aged guanaco bones, including sub-aerial weathering in a controlled environment, and water transport with disarticulated bones. Other studies were conducted at a local zoo, where we offered different types of prey to native small-sized carnivores (canids, felids, mustelids, and mephitids). Our naturalistic observations include the development of taphonomic transects in different environments. Through this method, we were able to study different topics among which some of the more significant are the movement of bones by small-sized carnivores and the distribution of beached Magellanic penguin specimens along the coast. Particular studies included the analyses of the content of dens occupied by small carnivores, the effects of a grassland fire in a vertebrate assemblage, the modifications produced by a local rodent -vizcacha- in the landscape, and the damage generated by pumas in guanaco carcasses. After ten years of systematic research we contributed to identify the potential mixture between modern bones and the archaeological record in relation to the environment; to determine bone preservation biases according to the properties of the record; to recognize agents responsible of bone accumulation and alteration; and to establish diagnostic criteria in order to differentiate cultural from natural patterns.
The archaeological record of Late Pleistocene Africa is characterized by behavioral diversity and change, notably the technological shift from the Middle Stone Age (MSA) to Later Stone Age (LSA). Recent research shows the MSA-LSA transition was a spatially and temporally complex process. Understanding this transition requires a composite record of archaeological sites from precise chronological and stratigraphic contexts within multiple regions. Here we present excavation and analysis of two open-air Late Pleistocene sites in chronological and geographic association: Anderea’s Farm 1 (GrJe-8) and Kapsarok 1 (GrJe-9), from the Nyanza Rift, Kenya. Volcanic ash correlations of artifact-bearing sediments provide ages of ∼ 45–36 ka for Anderea’s Farm 1 (GrJe-8) and ∼ 50 ka for Kapsarok 1 (GrJe-9). Locally procured lavas were used to produce different stone tools by disparate technological methods. Lithic production at Anderea’s Farm 1 focused on the manufacture of short irregular flakes using expedient and discoidal methods, and tools are dominated by heavy-duty types. In contrast, Kapsarok 1 is characterized by elongated and convergent blanks produced using hierarchical core technologies. Viewed together, Kapsarok 1 and Anderea’s Farm 1 emphasizes high diversity in Late Pleistocene technology of the Victoria Basin. We argue these different technologies are most parsimoniously interpreted as expressions of a broad and flexible behavioral repertoire. Further, our results emphasize how excavation and analysis of open-air archaeological sites in secure chronological and stratigraphic contexts provides the means to sample the necessary range of human behaviours across a landscape commensurate with past forager geographic ranges.
We present evidence that people in small-scale, mobile hunter-gatherer societies cooperated in large numbers to produce collective goods. Foragers engaged in large-scale communal hunts, constructed shared capital facilities; they made shared investments in improving the local environment; and they participated in warfare, alliance, and trade. Large-scale collective action often played a crucial role in subsistence. The provision of public goods involved the cooperation of many individuals, so each person made only a small contribution. This evidence suggests that large-scale cooperation occurred in the Pleistocene societies that encompass most of human evolutionary history, and therefore it is unlikely that large-scale cooperation in Holocene food producing societies results from an evolved psychology shaped only in small group interactions. Instead, large scale human cooperation needs to be explained as an adaptation, likely rooted in the distinctive features of human biology, grammatical language, increased cognitive ability, and cumulative cultural adaptation.
Cambridge Core - Archaeology of Asia, Sub-Saharan Africa and The Pacific - Prehistoric Stone Tools of Eastern Africa - by John J. Shea
The origins of complex projectile weaponry provides insight into cultural and biological changes associated with the origins and spread of modern human populations. Middle Stone Age backed pieces are often thought to be components of such armaments, however our limited understanding of their functional characteristics as projectiles precludes understanding the adaptive problems they may have solved. Despite acknowledgment of raw material differences and intra-assemblage variability, whether variability in backed piece form reflects functional, economic, or stylistic variation has a paucity of empirical support. Here, the functional differences in backed piece form (size and shape) while hafted transversely and obliquely as high-velocity complex projectile armatures are examined. If there are performance tradeoffs simply in how backed pieces are arranged at the end of armaments that can influence effectiveness, then identifying the archaeological arrangement can provide insight into what variables were being prioritized in prehistoric technological systems. How variation in backed piece size, elongation, and hafting arrangement influences complex projectile performance is tested using experimental and actualistic projectile replications with a calibrated crossbow against animal and ballistics gelatin targets. The results of this study show that, within the size and shape variation of silcrete backed pieces examined, tool form plays a relatively limited role in their performance as projectile armatures. However, hafting orientation has very different performance characteristics for complex projectiles shot at ballistics gelatin compared to animal targets. We demonstrate that transversely hafted tools have more lethal internal wounds, but obliquely hafted backed pieces have greater puncture reliability. These functional differences represent different technological design emphasis: transversely hafted tools create large, deep wounds, while obliquely hafted arrows and darts create a puncture more reliably. Although obliquely hafted armaments cause less internal trauma, they are more likely to penetrate the hide of ungulate prey. Variability in MSA hunting tactics may have played a role in the design of weapon systems to optimize these performance tradeoffs. Despite similarities in shape with ethno-historic technologies, based on these results, MSA-sized backed pieces hafted as projectile armatures were unlikely to have been used with small, low-powered bows - but would have been lethal with a high-velocity delivery system.
A study of bone orientation patterns at a wildebeest bonebed deposited in the floodplain of Lake Masek (Tanzania) shows that portions of the assemblage exhibit anisotropy probably caused by the combined action of lake transgression and regression, and the watersheet formed during the rainy season, which is also responsible for a large part of the microtopographical features of the surface where the bonebed was formed. Some taphonomic indicators (absence of polished or abraded bone, similar representation of Voorhies' anatomical groups I and III) show that the anisotropic trend was formed under very low-energy conditions. Anisotropy can be locally produced in autochthonous assemblages. Bone orientation patterns need to be combined with other taphonomic techniques to determine the depositional nature of any given assemblage.
To better understand the potential role of environmental change in mediating human dispersals across equatorial
East Africa, this study examines the biogeographic histories of ungulates, including a summary of current knowledge and fossil evidence stemming from our fieldwork in the Kenyan portion of the Lake Victoria
basin. Phylogeographic and paleontological evidence indicates that vegetation changes across Quaternary climate cycles mediated ungulate distributions and dispersals via the opening and closing of biogeographic barriers
in equatorial East Africa. Dispersal capabilities would have been enhanced during phases of grassland expansion and diminished during phases of grassland contraction. We propose that the distribution and dispersal of diagnostic technological markers in the archaeological record may be similarly influenced by environmental changes. The Middle Stone Age record from the Lake Victoria region provides intriguing examples of possible environmentally mediated technological dispersals.
This paper reviews the evidence for tooth marks made by sharks, crocodiles, dinosaurs, rodents, and especially mammalian carnivores on modern and fossil bones. The ecological and taphonomic information revealed in tooth marks, including: predator identity, prey preferences, and feeding behavior and ecology are discussed, and a compilation of metric measurements of taxon-specific modern and fossil mammalian carnivore tooth marks from the published literature is also provided. Some recommendations intended to improve the scope and scale of future tooth-damage research are also presented.
The effect of changing environment on the evolution of Homo sapiens is heavily debated, but few data are available from equatorial Africa prior to the last glacial maximum. The Karungu deposits on the northeast coast of Lake Victoria are ideal for paleoenvironmental reconstructions and are best studied at the Kisaaka site near Karunga in Kenya (94 to N33 ka) where paleosols, fluvial deposits, tufa, and volcaniclastic deposits (tuffs) are exposed over a ~2 km transect. Three well-exposed and laterally continuous paleosols with intercalated tuffs allow for reconstruction of a succession of paleocatenas. The oldest paleosol is a smectitic paleo-Vertisol with saline and sodic properties. Higher in the section, the paleosols are tuffaceous paleo-Inceptisols with Alfisol-like soil characteristics (illuviated clay). Mean annual precipitation (MAP) proxies indicate little change through time, with an average of 764 ± 108 mm yr −1 for Vertisols (CALMAG) and 813 ± 182 to 963 ± 182 mm yr −1 for all paleosols (CIA-K). Field observations and MAP proxies suggest that Karungu was significantly drier than today, consistent with the associated faunal assemblage, and likely resulted in a significantly smaller Lake Victoria during the late Pleistocene. Rainfall reduction and associated grassland expansion may have facilitated human and faunal dispersals across equatorial East Africa.
The paper describes diagnostic characteristics of damage inflicted by large felids, canids, ursids, and hyenids to femora and tibiae of large mammals (body mass 300 kg or larger). The information may be applicable to studies of fossil bone assemblages. An understanding of patterns in carnivore utilization of prey carcasses in the past may provide clues to prey availability or vulnerability.
A review of the available archaeological, ethnographic, and historical data reveals that there is compelling evidence for communal pronghorn hunting across western North America in theprotohis-toric and early historic periods. The evidence is particularly compelling for the Great Basin, where corrals were in common use, as well as for the Great Plains, where drives into corrals or pits were common. Evidence for such CKtivities in the remote past, including projectile point concentrations, hunting facilities, and bonebed sites, is considerably sparser and more ambiguous. Nonetheless, it appears that communal pronghorn hunting did not decrease through time, but rather was maintained or has increased within the last 1,500 years.
The tephrostratigraphic framework for Pliocene and Early Pleistocene paleoanthropological sites in East Africa has been well established through nearly 50 years of research, but a similarly comprehensive framework is lacking for the Middle and particularly the Late Pleistocene. We provide the first detailed regional record of Late Pleistocene tephra deposits associated with artifacts or fossils from the Lake Victoria basin of western Kenya. Correlations of Late Pleistocene distal tephra deposits from the Wasiriya beds on Rusinga Island, the Waware beds on Mfangano Island and deposits near Karungu, mainland Kenya, are based on field stratigraphy coupled with 916 electron microprobe analyses of eleven major and minor element oxides from 50 samples. At least eight distinct distal tephra deposits are distinguished, four of which are found at multiple localities spanning >60 km over an approximately north to south transect. New optically stimulated luminescence dates help to constrain the Late Pleistocene depositional ages of these deposits. Our correlation and characterization of volcaniclastic deposits expand and refine the current stratigraphy of the eastern Lake Victoria basin. This provides the basis for relating fossil- and artifact-bearing sediments and a framework for ongoing geological, archaeological and paleontological studies of Late Pleistocene East Africa, a crucial time period for human evolution and dispersal within and out of Africa.
Ongoing archaeological research at North Lake Eyasi has produced a wealth of information, including a new hominid fossil and several archaeological sites dating to the end of the Middle Pleistocene. One of the sites (WB9) has been excavated and has produced evidence of multiple processes in its formation, including evidence of functional associations of stone tools and faunal remains which are scarce for this time period. The stone tool industry is based on a core and flake industry, which is not very diagnostic and attributed to MSA. Earlier heavy-duty tools classified as Sangoan may derive from the underlying Eyasi Beds. The stratigraphic provenience of previous fossil hominids is unknown. Surface collections from the Eyasi lake, thus, comprise two different sets of stone tools and fossils, which can only be clearly differentiated in the field. This advises against the use of previously curated collections as a homogeneous sample. Earlier definitions of the Njarasa industry should be revised. This work presents results on the paleoecology of the area and of its paleontological and archaeological information, with special reference to the excavation of WB9, the most complete site discovered in the area so far. This contributes to the limited information available about site functionality and hominid subsistential behaviour in East Africa during the end of the Middle Pleistocene. A technological study from WB9 also shows the variability of stone tool traditions at this time.
Modern East African savannas serve as the primary model for the paleoenvironments of early hominids. However, throughout the Neogene there have been cooling and drying trends through time and fluctuations in seasonality. As a result, many modern East African savannas are drier, with more severe dry seasons, than during some periods in the Plio/Pleistocene in which early hominids lived. Our understanding of these moister and less seasonal periods is crucial for reconstructing early hominid lifeways. This paper presents a study of the ecology and bone taphonomy of a savanna less dry and less seasonal than the East African ones, the Central African savanna in Parc National des Virunga, Zaire. The natural bone distributions across the landscape of Parc National des Virunga contain information about the spatial distribution of scavenging opportunities and the effects on bone deposition of ecological variables such as large-herbivore biomass, proximity to water, and tree density. This information is a significant for taphonomic interpretation of fossil distributions in paleosols and the paleoecology of hominid scavenging. My results indicate that the Central African savanna differs in bone distributions and scavenging opportunities from the savannas of East Africa. Bone deposition is higher in open grasslands than in wooded areas near rivers, and there is no dry-season glut of carcasses. There is also no evidence for increased bone deposition near permanent water or ephemeral water holes. These differences are ultimately the result of the less seasonal rainfall pattern. For early periods in human evolution, Central African savannas may be a useful analog, and the implications for site formation and the ecology of scavenging are profound.
Kenya National Museums Lukenya Hill Hominid 1 (KNM-LH 1) is a Homo sapiens partial calvaria from site GvJm-22 at Lukenya Hill, Kenya, associated with Later Stone Age (LSA) archaeological deposits. KNM-LH 1 is securely dated to the Late Pleistocene, and samples a time and region important for understanding the origins of modern human diversity. A revised chronology based on 26 accelerator mass spectrometry radiocarbon dates on ostrich eggshells indicates an age range of 23,576–22,887 y B.P. for KNM-LH 1, confirming prior attribution to the Last Glacial Maximum. Additional dates extend the maximum age for archaeological deposits at GvJm-22 to >46,000 y B.P. (>46 kya). These dates are consistent with new analyses identifying both Middle Stone Age and LSA lithic technologies at the site, making GvJm-22 a rare eastern African record of major human behavioral shifts during the Late Pleistocene. Comparative morphometric analyses of the KNM-LH 1 cranium document the temporal and spatial complexity of early modern human morphological variability. Features of cranial shape distinguish KNM-LH 1 and other Middle and Late Pleistocene African fossils from crania of recent Africans and samples from Holocene LSA and
European Upper Paleolithic sites.
The effect of changing palaeoclimate and palaeoenvironment on human evolution during the Pleistocene is debated, but hampered by few East African records directly associated with archaeological sites prior to the Last Glacial Maximum. Middle to Late Pleistocene deposits on the shoreline of eastern Lake Victoria preserve abundant vertebrate fossils and Middle Stone Age arte-facts associated with riverine tufas at the base of the deposits, which are ideal for palaeoenvironmental reconstructions. New data from tufas identified on Rusinga Island and on the mainland near Karungu, Kenya are provided from outcrop, thin sections, mineralogical, stable isotopic and U-series dating analyses. Tufa is identified in four sites: Nyamita (94·0 ± 3·3 and 111·4 ± 4·2 ka); Kisaaka, Aringo (455 ± 45 ka); and Obware. The age ranges of these tufa deposits demonstrate that spring-fed rivers were a recurrent, variably preserved feature on the Pleistocene landscape for ca 360 kyr. Poor sorting of clastic facies from all sites indicates flashy, ephemeral discharge, but these facies are commonly associated with barrage tufas, paludal environments with δ13C values of ca 10‰ indicative of C3 plants and fossil Hippopotamus, all of which indicate a perennial water source. Other tufa deposits from Nyamita, Obware and Aringo have a mixed C3/C4 signature consistent with a semi-arid C4 grassland surrounding these spring-fed rivers. The δ18O values of tufa from Nyamita are on average ca 1‰ more negative than calcite precipitated from modern rainfall in the region, suggesting greater contribution of depleted monsoonal input, similar to the Last Glacial Maximum. Microdebitage and surface-collected artefacts indicate that early modern humans were utilizing these spring-fed rivers. The presence of spring−fed rivers would have afforded animals a reliable water source, sustaining a diverse plant and animal community in an otherwise arid environment.
Online: http://www.unr.edu/Documents/liberal-arts/anthropology/gary-haynes/haynes-paleobiol80.pdf
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Based on inspection of gnawing damage done to bones of modern prey animals, sets of typical damage types or patterns are recognized for certain elements. The presence of these damage patterns suggests carnivore activity even when bones exhibit no identifiable tooth marks or other obvious sign of gnawing. Observations are made of these damage types on bones of Pleistocene and Recent North American mammals, including Bison, proboscidean, Alces, Equus, Cervus, and Rangifer. Damage to the following elements is briefly described: antlers, vertebrae, scapulae, humeri, ulnae, radii, femora, tibiae, metapodials, and innominates.
Bones of recent mammals in the Amboseli Basin, southern Kenya, exhibit distinctive weathering characteristics that can be related to the time since death and to the local conditions of temperature, humidity and soil chemistry. A categorization of weathering characteristics into six stages, recognizable on descriptive criteria, provides a basis for investigation of weathering rates and processes. The time necessary to achieve each successive weathering stage has been calibrated using known-age carcasses. Most bones decompose beyond recognition in 10 to 15 yr. Bones of animals under 100 kg and juveniles appear to weather more rapidly than bones of large animals or adults. Small-scale rather than widespread environmental factors seem to have greatest influence on weathering characteristics and rates. Bone weathering is potentially valuable as evidence for the period of time represented in recent or fossil bone assemblages, including those on archeological sites, and may also be an important tool in censusing populations of animals in modern ecosystems.
The fossil record provides tangible, historical evidence for the mode and operation of evolution across deep time. Striking patterns of convergence are some of the strongest examples of these operations, whereby, over time, similar environmental and/or behavioral pressures precipitate similarity in form and function between disparately related taxa. Here we present fossil evidence for an unexpected convergence between gregarious plant-eating mammals and dinosaurs. Recent excavations of Late Pleistocene deposits on Rusinga Island, Kenya, have uncovered a catastrophic assemblage of the wildebeest-like bovid Rusingoryx atopocranion. Previously known from fragmentary material, these new specimens reveal large, hollow, osseous nasal crests: a craniofacial novelty for mammals that is remarkably comparable to the nasal crests of lambeosaurine hadrosaur dinosaurs. Using adult and juvenile material from this assemblage, as well as computed tomographic imaging, we investigate this convergence from morphological, developmental, functional, and paleoenvironmental perspectives. Our detailed analyses reveal broad parallels between R. atopocranion and basal Lambeosaurinae, suggesting that osseous nasal crests may require a highly specific combination of ontogeny, evolution, and environmental pressures in order to develop.
Large cats, canids, bears, and hyenas create distinctive types of damage when they gnaw bones. This paper describes the diagnostic characteristics of damage done by each taxon to femora and tibiae of herbivores with body weights = or >300kg. Pleistocene and Recent fossil collections that include gnawed bones might provide data on the presence of carnivores whose own remains are not found in the collections. Information might also be gained about predator and scavenger utilization of prey carcasses, often a reflection of prey vulnerability or availability in past communities.-Author
Late Pleistocene sedimentary, biogeochemical, and fossil data from the Lake Victoria basin (the largest lake in Africa) suggest that its reduction or desiccation during periods of increased aridity repeatedly facilitated the dispersal of C4 grassland ecosystems across the basin. Archaeological evidence from Middle Stone Age and Later Stone Age sites suggest that human groups diffused into the basin during intervals of declining lake levels, likely tracking the movement of the dense and predictable resources of shoreline environments, as well as the dense but less predictable C4 grass grazing herbivores. Repeated cycles of lake expansion and contraction provide a push–pull mechanism for the isolation and combination of populations in Equatorial Africa that may contribute to the Late Pleistocene human biological variability suggested by the fossil and genetic records. Latitudinal differences in the timing of environmental change between the Lake Victoria basin and surrounding regions may have promoted movements across, within, and possibly out of Africa.
In this book, Robert L. Kelly challenges the preconceptions that hunter-gatherers were Paleolithic relics living in a raw state of nature, instead crafting a position that emphasizes their diversity, and downplays attempts to model the original foraging lifeway or to use foragers to depict human nature stripped to its core. Kelly reviews the anthropological literature for variation among living foragers in terms of diet, mobility, sharing, land tenure, technology, exchange, male–female relations, division of labor, marriage, descent and political organization. Using the paradigm of human behavioral ecology, he analyzes the diversity in these areas and seeks to explain rather than explain away variability, and argues for an approach to prehistory that uses archaeological data to test theory rather than one that uses ethnographic analogy to reconstruct the past.
Age determination methods for the blue wildebeest employed the use of tooth eruption sequence, cementum layers from macroscopic tooth sections, eye lens mass, and tooth attrition. Eleven eruption classes were arrived at, providing a reliable method of age determination up to 3,5 years. The times of eruption of specific teeth were compared with data from East Africa. The restricted birth interval of wildebeest enabled some sub-adult animals to be regarded as ‘known-age’ which were used to arrive at a value for the number of cementum layers laid down per annum, and to provide a ‘correction factor’ for the period before eruption and cemental deposition. The nature of tooth cementum lines in wildebeest is discussed, and changes in infundibular patterns were related to cementum or eruption age, providing an age-wear chart with 14 adult classes, adequate for life-table data. Incisiform wear in wildebeest appears to follow a curvilinear relationship. When eye lens mass was plotted against cementum or eruption age, the resultant curve served only to distinguish between animals below one year old and the older age classes. Anomalies in dentition are discussed. Some criteria for age determination in the field are presented.Ouderdomsbepalingsmetodes vir die blouwiidebees het die gebruik van tandsnypatrone, tandsementumlae in makroskopiese deursnitte, ooglensmassa en tandslytasie ingesluit. Elf tandsnyklasse, as 'n betroubare metode vir ouderdomsbepaling tot 3,5 jaar is geidentifiseer. Die sny van spesifieke tande is met gegewens uit Oos-Afrika vergelyk. Die beperkte kalfseisoen van wildebeeste het daartoe gelei dat die ouderdom van sommige onvolwasse diere as bekend beskou kan word, en is gebruik om te bepaal hoeveel sementumlae jaarliks neergelS word en om 'n korreksiefaktor vir die periode voor die sny en sementumring neerlegging te verskaf. Die aard van tandsementumlyne in wildebeeste word bespreek. Die veranderlnge In infundibulere patrone is met sementum- of tandsnyouderdom vergelyk, en 'n ouderdomslytasiekaart met 14 klasse vir volwasse diere vir lewenstabelgegewens kon opgestel word. Snytandslytasie in wildebeeste volg blykbaar 'n kromlynige verwantskap. Die verwantskap tussen ooglensmasse en sementum- of tandsnyouderdom kan slegs diere jonger as een jaar van diere in ander ouderdomsgroepe onderskei. Afwyking in tandekry word bespreek. Etlike maatstawwe vir ouderdomsbepaling in die veld wordaangebied.
A model for attritional bone assemblage formation in fluvial deposits, based on observations of taphonomic processes in modern environments, provides order-of-magnitude estimates for time intervals represented in single unit, 'contemporaneous' vertebrate samples.-from Author Dept of Paleobiology, National Museum of Natural History, Smithsonian Inst, Washington, DC 20560, USA.
The opening and closing of the equatorial East African forest belt during the Quaternary is thought to have influenced the biogeographic histories of early modern humans and fauna, although precise details are scarce due to a lack of archaeological and paleontological records associated with paleoenvironmental data. With this in mind, we provide a description and paleoenvironmental reconstruction of the Late Pleistocene Middle Stone Age (MSA) artifact- and fossil-bearing sediments from Karungu, located along the shores of Lake Victoria in western Kenya. Artifacts recovered from surveys and controlled excavations are typologically MSA and include points, blades, and Levallois flakes and cores, as well as obsidian flakes similar in geochemical composition to documented sources near Lake Naivasha (250 km east). A combination of sedimentological, paleontological, and stable isotopic evidence indicates a semi-arid environment characterized by seasonal precipitation and the dominance of C4 grasslands, likely associated with a substantial reduction in Lake Victoria. The well-preserved fossil assemblage indicates that these conditions are associated with the convergence of historically allopatric ungulates from north and south of the equator, in agreement with predictions from genetic observations. Analysis of the East African MSA record reveals previously unrecognized north-south variation in assemblage composition that is consistent with episodes of population fragmentation during phases of limited dispersal potential. The grassland-associated MSA assemblages from Karungu and nearby Rusinga Island are characterized by a combination of artifact types that is more typical of northern sites. This may reflect the dispersal of behavioral repertoires-and perhaps human populations-during a paleoenvironmental phase dominated by grasslands.
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Mortality profiles have figured prominently among tools used by zooarchaeologists to investigate relationships between hominids and prey species. Their analysis and interpretation have been considerably influenced by M.C. Stiner’s approach based on ternary diagrams. Part of this method included the demarcation of “zones” in ternary diagrams identifying specific mortality patterns (e.g. attritional, catastrophic, prime-dominated, etc.). Since its introduction some twenty-five years ago, this zoning has, however, received little critical attention. Mathematical modelling as well as a reassessment of the ecological data used to define these zones reveal several problems that may bias interpretations of mortality profiles on ternary diagrams.
Eastern Africa is an important area to study early populations of Homo sapiens because subsets of those populations likely dispersed to Eurasia and subsequently throughout the globe during the Upper Pleistocene. The Middle Stone Age (MSA) archaeology of this region, particularly aspects of stone-tool technology and typology, is highly variable with only rare cases of geographic and temporal patterning. Although there are differences in timing and perhaps frequency of occurrence, those elements that make up the MSA lithic tool kit are also found at contemporaneous sites elsewhere in Africa and Eurasia, making it difficult to identify a unique archaeological signal for hominin dispersals out of eastern Africa. Rather, regional variation appears to be the outcome of possibly long-term interactions between particular physical and social environments experienced by hominin populations.
Wildebeest drownings produce dense bone deposits over large surface areas adjacent to lakes and rivers in the Serengenti ecosystem of East Africa. Drownings occur during the annual wildebeest migration when animals cross rivers and lakes on their way to wet season pastures. Drownings involve both small and large numbers of adult and newborn wildebeest and can occur in a single event or a sequence of small and large events during the wet season.Signature criteria from surface skeletal remains produced by modern drownings that may, as an integrated set, help to identify them in the fossil record include: (1) the predominance of adults from a single species and the variable representation of newborns and yearlings; (2) the presence of intact elements from all adult skeletal groups; (3) assemblages dominated by axial elements and long bones; and (4) negative correlations between the representation of long bones and their marrow wet weights; assemblages from large drowning events possess weak negative correlations while small events possess strong negative correlations. The application of these criteria requires a landscape sampling strategy, because the drowning event's signature can be spread out over hundreds or thousands of metres of river or lake front. Consequently, localized samples from a large drowning may be affected differently by carnivores, flowing water, trampling, weathering, and/or burial and not possess all of these signature criteria.Drownings represent important scavenging opportunities for a wide variety of consumers because of the number of carcasses they can produce. Their occurrence in rivers and lakes also gives them some seasonal and spatial predictability. Under these circumstances, it is possible that water-restricted early hominids may have gained relatively early access to large animal carcasses without recourse to hunting or confrontational scavenging. Early access to carcasses would have been facilitated by the simultaneous presence of many drowned individuals over a large area, because these conditions act to reduce inter- and intra-specific competition for carcass foods among consumers. Later access to carcasses could still have provided hominids with a wealth of nutritious long bone marrow and cranial contents.
Intertaxonomic differences in skeletal element representation in archaeological faunas may reflect preferences in the procurement, processing, transport, and/or consumption of these species by prehistoric foragers. However, the possibility that they also may result from preservational bias must be addressed before behavioral attributes of human hunters may be inferred. For example, at many archaeological sires, the remains of equids exhibit a different pattern of skeletal skeletal element representation than those of bovids and cervids. To evaluate the significance of such differences, this study examines intertaxonomic variability in patterns of bone density, the attribute most commonly employed as a proxy measure of resistance resistance to destructive processes. Density data derived for a bovid (Connachaetes taurinus), a cervid (Rangifer tarandus), and two species of equid (Equus burchelli and E. przewalskii) exhibited very similar patterns, suggesting that values for one species may be used to interpret the survival patterns for other species of generally similar morphology. The differences in skeletal element representation between bovid, cervid, and equid species observed in archaeological faunas do riot correspond with bane density and thus likely indicate selective treatment by human or other biotic agents.
Experiments that recorded the dispersal of 142 bones within a meandering, 2030 m-long reach of the East Fork River, Wyoming over a 13-year period provide a basis for interpreting distribution patterns and time averaging in fossiliferous channel deposits. Results show that light and porous bones, were transported farther than heavy bones. Bones became sorted by size and shape within 1 to 2 years and sorting patterns varied according to initial channel position. The combined distribution of bones from all the experimental sets, however, was unsorted and generally random.
In a paper published in 2000, McBrearty and Brooks argued for the cognitive unity of Homo sapiens as a species. We asserted that the cognitive abilities of early members of our species were indistinguishable from our own, and that the early signs of this ability appear in the record of the African Middle Stone Age. Innovations were produced by the normal process of invention and do not require special genetic mutations to explain them. Gaps in the spatial and temporal distribution of archaeological traits are a normal product of the nature of the archaeological record. In this paper I review research since 2000 and conclude that it has vindicated this view and has begun to fill in perceived gaps in the African record for early behavioral modernity.
