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Oldowan sites in primary geological context are rare in the archaeological record. Here we describe the depositional environment of Oldowan occurrences at Kanjera South, Kenya, based on field descriptions and granulometric analysis. Excavations have recovered a large Oldowan artefact sample as well as the oldest substantial sample of archaeological fauna. The deposits at Kanjera South consist of 30 m of fluvial, colluvial and lacustrine sediments. Magneto- and biostratigraphy indicate the Kanjera South Member of the Kanjera Formation was deposited during 2.3–1.92 Ma, with 2.0 Ma being a likely age for the archaeological occurrences. Oldowan artefacts and associated fauna were deposited in the colluvial and alluvial silts and sands of beds KS1–3, in the margins of a lake basin. Field descriptions and granulometric analysis of the sediment fine fraction indicate that sediments from within the main archaeological horizon were emplaced as a combination of tractional and hyperconcentrated flows with limited evidence of debris-flow deposition. This style of deposition is unlikely to significantly erode or disturb the underlying surface, and therefore promotes preservation of surface archaeological accumulations. Hominins were repeatedly attracted to the site locale, and rapid sedimentation, minimal bone weathering and an absence of bone or artefact rounding further indicate that fossils and artefacts were quickly buried.

The current study provides the first zooarchaeological account of systematically excavated faunal material from Elandsfontein, South Africa (ca. 1.0 – 0.6 Ma). Archaeological assemblages of this age typically lack well-preserved faunal remains recovered in primary association with artifacts, and thus studies have primarily focused on lithic technology. The sizeable faunal sample from Elandsfontein, South Africa is a rare exception and has dramatically influenced the way that we interpret early hominin foraging behavior during this time. Surface collections, starting in the 1950s, recovered ~13,000 mammalian fossils and more than 160 Acheulean artifacts. The Elandsfontein faunal assemblage was interpreted as having accumulated through natural mortality and subsequent scavenging by carnivores and hominins, with hominins playing a very minimal role in carcass modification. Low frequencies of stone tool cutmarks were taken as evidence that Acheulean hominins had limited ability to obtain large carcasses. However, this interpretation contrasts with a growing body of evidence suggesting that many Acheulean hominins across sub-Saharan Africa not only had access to large mammal carcasses but were often the primary agents of accumulation and modification. The majority of the original Elandsfontein faunal material was collected from deflation surfaces and lacks sufficient contextual information. We conducted a detailed zooarchaeological analysis of faunal remains from four recent excavations within the Elandsfontein dune field. Our results differ from those based on surface collections and suggest multiple agents of bone accumulation with varying degrees of hominin and carnivore activity across the paleolandscape. Frequencies of hominininduced butchery are higher (up to 3.6% NISP) than reported for previously collected samples (

The archaeological and paleontological records from the west coast of South Africa have potential to provide insights into ecosystem dynamics in the region during the mid Pleistocene. Although the fossil record suggests an ecosystem quite different than that of the region today, we understand little about the ecological factors that contributed to this disparity. The site of Elandsfontein (EFT) dates to between 1.0 and 0.6 million years ago (Ma), preserves in situ lithic and faunal materials found in direct association with each other, and provides the rare opportunity to examine the relationship between hominin behavioural variability and landscape heterogeneity in a winter rainfall ecosystem. In this study, we examine the stable carbon isotopic composition of a large sample (n = 81) of Cape dune mole-rats (Bathyergus suillus) and contemporaneous large mammals (> 6 kg; n = 194) from EFT. We find that δ13C values of B. suillus are significantly different to those of contemporaneous large mammals from EFT indicating a significant presence of plants utilizing the C4 photosynthetic pathway during the mid-Pleistocene, in contrast to present C3 dominated ecosystems along the west coast of South Africa. Additionally, we find that artifact density at EFT localities is positively correlated with δ13C values in B. suillus enamel suggesting that evidence of more intense hominin occupation may be associated with the presence of more C4 vegetation. Lastly, we hypothesize that this unique distribution of vegetation 1) provided abundant resources for both hominin and non-hominin taxa and 2) may have concentrated hominin and animal behavior in certain places on the ancient landscape.

Nearly all primates are ecologically dependent on trees, but they are nonetheless found in an enormous range of habitats, from highly xeric environments to dense rainforest. Most primates have a relatively ‘generalised’ skeleton, enabling locomotor flexibility and facilitating other crucial functions, such as manual foraging and grooming. This paper explores the associations between habitat, locomotion and morphology in the forelimbs of cercopithecids (Old World monkeys), contextualising their skeletal ecomorphological patterns with those of other mammals, and complementing functional morphological analyses with phylogenetic comparative techniques. The ecomorphological signals present in the generalised primate postcranium, and how an ancestral arboreal ‘bauplan’ might be modified to incorporate terrestriality or exploit distinct arboreal substrates, are investigated. Analysis of ecomorphological variation in guenons indicates that terrestrial Chlorocebus species retain core elements of a general guenon form, with modifications for terrestriality that vary by species. Adaptation to different modes of arboreality has also occurred in Cercopithecus. The considerable morphological similarity in the guenons sampled emphasises the importance of generality in the primate postcranium – much forelimb variation appears to have emerged stochastically, with a smaller number of traits having a strong functional signal. Analysis of a broader sample of cercopithecids and comparison with felids, suids and bovids indicates that although the cercopithecid humerus has functional morphological signals that enable specimens to be assigned with a reasonable degree of certainty to habitat groups, there is considerable overlap in the specimens assigned to each habitat group. This probably reflects ecological dependence on trees, even in predominantly terrestrial species, as well as the multiple functions of the forelimb and, in some cases, wide geographic distributions that promote intraspecific variation. The use of phylogenetic correction reduced the discriminatory power of the models, indicating that, like allometry, phylogeny contains important ecomorphological information, and should not necessarily be factored out of analyses.

The current understanding of landscape scale variation in mid-Pleistocene hominin behavior is limited. Most of our understanding derives from a few localities in eastern Africa. Consequently, we know very little about hominin landscape use outside this region, despite the fact that mid-Pleistocene hominins occupied other climatic zones including temperate, and mid-latitude ecosystems. The winter rainfall zone in South Africa represents one of the world's most diverse ecosystems. Although mammal diversity is relatively low in these habitats this is compensated by the tremendous floral diversity. Buried Pleistocene land surfaces in the region provide an opportunity to understand how humans adapted to this unique, mid-latitude environment prior to the Last Interglacial. The dunefield locality of Elandsfontein in the Western Cape of South Africa is one of the richest known paleontological and archeological sites in southern Africa. It records details of landscape formation history, enabling detailed reconstruction of the ancient environments in this winter rainfall-dominated region. This dunefield archive allows us to posit the taphonomic history of newly excavated archaeological material and previously collected specimens. Here we provide initial results from the excavation and geological analysis of the Elandsfontein dunefield and provide new insights into the formation history of the archaeological and paleontological deposits. This includes indications of multiple pedogenic intervals and groundwater table fluctuations. The combination of geological, paleontological and archaeological data provides a framework for evaluating how hominins interacted with the unique ecosystems of the Cape Floral Region of South Africa during the mid-Pleistocene.

Mammalian carnivores are rarely incorporated in paleoenvironmental reconstructions, largely because of their rarity within the fossil record. However, multivariate statistical modeling can be successfully used to quantify specific anatomical features as environmental predictors. Here we explore morphological variability of the humerus in a closely related group of predators (Felidae) to investigate the relationship between morphometric descriptors and habitat categories. We analyze linear measurements of the humerus in three different morphometric combinations (log-transformed, size-free, and ratio), and explore four distinct ways of categorizing habitat adaptations. Open, Mixed, and Closed categories are defined according to criteria based on traditional descriptions of species, distributions, and biome occupancy. Extensive exploratory work is presented using linear discriminant analyses and several fossils are included to provide paleoecological reconstructions.We found no significant differences in the predictive power of distinct morphometric descriptors or habitat criteria, although sample splitting into small and large cat guilds greatly improves the stability of the models. Significant insights emerge for three long-canine cats:Smilodon populator,Paramachairodus orientalis, andDinofelissp. from Olduvai Gorge (East Africa).S. populatorandP. orientalisare both predicted to have been closed-habitat adapted taxa. The false “sabertooth”Dinofelissp. from Olduvai Gorge is predicted to be adapted to mixed habitat. The application of felid humerus ecomorphology to the carnivoran record of Olduvai Gorge shows that the older stratigraphic levels (Bed I, 1.99–1.79 Ma) included a broader range of environments than Beds II or V, where there is an abundance of cats adapted to open environments.

The middle Pleistocene fossil mammal assemblage from Lainyamok in the southern Kenya rift has previously been considered the oldest (330-392 ka) African mammal community consisting entirely of extant species, with the dominant bovid tentatively attributed to the southern African blesbok (Damaliscus cf. dorcas). We show that the blesbok-like fossils from Lainyamok belong to an extinct species, described here as Damaliscus hypsodon sp. nov. The D. hypsodon hypodigm includes the previously unnamed small alcelaphine material known from late Pleistocene sites elsewhere in Kenya and Tanzania. Its dental anatomy, together with an ecomorphological analysis of its postcrania, indicates that D. hypsodon grazed in open and arid grassland environments. Although Lainyamok is no longer represented entirely by extant species, the absence of species common earlier in the middle Pleistocene of East Africa suggests substantial faunal turnover between 500 and 400 ka. Damaliscus hypsodon persisted in East Africa until the end of the Pleistocene and its extinction can be attributed to a loss of arid grassland environments at the onset of the Holocene. The fossil evidence from southern Kenya suggests that the development of the taxonomically modern large mammal community was a long-term process characterized by the extinction of grazing specialists, with marked turnover occurring between ~ 500 and 400 ka and near the end of the Pleistocene.

Morphological convergence amongst species inhabiting similar environments but having different evolutionary histories is a concept central to evolutionary biology. Cases of divergent evolution, where there is morphological divergence between closely related species exploiting different environments, are less well studied. Here we show divergent evolution in the morphology of the proximal phalanges of several closely related African antelope species inhabiting different environments. This morphological divergence was consistently observed in both a neutral morphospace and an externally ordinated morphospace. Divergence, but not convergence, was also observed when size and shape were considered independently. Finally, convergent evolution of the morphology of the proximal phalanges was observed, but only in the externally ordinated morphospace. Size shows less correlation with phylogeny than does shape. Therefore, we suggest that divergence in size will occur more readily when a species encounters new environmental conditions than divergence in shape. These findings are compatible with observations of rapid dwarfing on islands (Foster’s rule).

Analysis of dental mesowear is a useful tool to examine dietary strategies in ungulates, and provides a palaeoenvironmental proxy at archaeological and palaeontological sites. We examine the distribution of traditional qualitative mesowear variables amongst 33 species of extant African antelope. We also examine the relationship of our dataset with the original dataset of Fortelius and Solounias (2000) . We find that confining mesowear analyses to antelope species alone reduces their discriminating power relative to that found in analyses using a broader range of taxa. Variability in mesowear scores along the toothrow suggest that different teeth do not wear equivalently over an individual’s life-time, so it is important to confine comparisons to individual tooth positions for palaeodietary classifications. Mesowear scores from the third upper molar were found to have the greatest discriminating power. Frugivores displayed unique mesowear signatures, suggesting that this trophic guild should be taken into consideration separately in future mesowear analyses. These results have implications which can improve the application and the discriminatory power of mesowear analyses for the determination of the palaeodiets of extinct taxa, and, by extension, their palaeoenvironments.

Aim To quantify how mammal community structure relates to heterogeneity of vegetation for palaeoecological reconstructions, and to test whether historical or environmental factors are more important in structuring communities. Location Sixty-three natural protected areas in Asia, Africa and South and Central America. Methods We defined faunal communities by allocating species to ecological guilds and calculating proportional representation within each guild. Vegetation heterogeneity for each natural protected area was calculated from satellite images. The relationship between these ecospaces was calculated using canonical correlations analysis, redundancy analysis and principal components analysis. We expected that large, herbivorous mammals would be most strongly correlated with open areas. Convergence was tested by independently eliminating the effects of geography and vegetation heterogeneity on the structure of the mammal communities. We expected that vegetation would more strongly structure communities than geographical position. Results We show that the guild structure of communities across habitats is significantly correlated with vegetation heterogeneity. The highest correlation was between small, scansorial-arboreal secondary consumers and heavy tree cover. The first convergence analysis shows American communities distinguished from Asian and African communities; these latter communities show a remarkable convergence in structure. Historical factors only affected the continent whose mammals had experienced a long period of isolation. The second convergence analysis shows that almost all biomes have the same or very similar community structure regardless of continent. Main conclusions Communities from the same environments in different continents showed remarkable convergence. Communities from the same continents only converged when those continents shared a recent geological and biological history. These results suggest that historical and environmental factors are operating over different timescales. This study confirms that environmental reconstructions made on the basis of whole communities will accurately reflect the environment that the community lived in. However, reconstructions made for fossil sites in deep time need to take historical factors into consideration. Small, arboreal and scansorial secondary consumers show the strongest correlation with vegetation, correlating with continuous tree canopy cover. This relationship allows simple reconstructions of the amount of tree cover occurring in a landscape from the proportion of species from the community falling in this ecological guild.

The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.

The habitat preferences of fauna found at palaeontological and archaeological sites can be used to investigate ancient environments and hominin habitat preferences. Here we present a discriminant function model linking astragalus morphology to four broadly defined habitat categories (open, light cover, heavy cover, and closed) using modern bovids of known ecology. Twenty-four measurements were taken on a sample of 286 astragali from 36 extant African antelope species. These measurements were used to generate ratios reflecting shape. An 11 variable discriminant function model was developed that had high classification success rates for complete astragali. Resubstitution analysis, jackknife analysis, and the classification of several “test samples” of specimens suggest that the predictive accuracy of this model is around 87%. The total classification success rates of 87% (jackknifed) or 93% (resubstitution) are considerably higher than those derived in another study of bovid astragalus ecomorphology (67%; [DeGusta, D., Vrba, E.S., 2003. A method for inferring palaeohabitats from the functional morphology of bovid astragali. J. Archaeol. Sci. 30, 1009–1022]) that used a more limited measurement scheme and a smaller sample of bovids than the present study. Different approaches to operationalizing ecomorphic analyses are considered in order to best extract accurate palaeoenvironmental information from palaeontological and archaeological datasets.

The archaeological record of Oldowan hominins represents a diverse behavioral system. It has been suggested that exploitation of lithic resources by Oldowan hominins was simplistic and represented mostly use of local sources of stone. Here we investigate the raw material selection and transport behaviors of Oldowan hominins reflected in the stone artifact assemblages from the Kanjera South Formation, South Rachuonyo District, Kenya. Using geochemical methods (ED-XRF) artifacts are linked to primary and secondary source outcrops throughout southwestern Kenya. These data show that hominins selected raw materials for transport at frequencies that are significantly different from their availability on ancient landscapes. Furthermore, a substantial proportion of the assemblage represents transport over relatively long distances (>10 km). Our study further suggests that in the early stages of stone tool use hominins used a wide variety of raw materials and selected these materials at some distance from their eventual discard locations. Early hominin behavior may have incorporated an understanding of raw material source distributions across a more extensive landscape than has been previously documented. This supports the growing perspective that Oldowan technology represents a more complex behavioral pattern than is usually associated with the beginnings of hominin tool use.

We test the performance of two models that use mammalian communities to reconstruct multivariate palaeoenvironments. While both models exploit the correlation between mammal communities (defined in terms of functional groups) and arboreal heterogeneity, the first uses a multiple multivariate regression of community structure and arboreal heterogeneity, while the second uses a linear regression of the principal components of each ecospace. The success of these methods means the palaeoenvironment of a particular locality can be reconstructed in terms of the proportions of heavy, moderate, light, and absent tree canopy cover. The linear regression is less biased, and more precisely and accurately reconstructs heavy tree canopy cover than the multiple multivariate model. However, the multiple multivariate model performs better than the linear regression for all other canopy cover categories. Both models consistently perform better than randomly generated reconstructions. We apply both models to the palaeocommunity of the Upper Laetolil Beds, Tanzania. Our reconstructions indicate that there was very little heavy tree cover at this site (likely less than 10%), with the palaeo-landscape instead comprising a mixture of light and absent tree cover. These reconstructions help resolve the previous conflicting palaeoecological reconstructions made for this site.

This paper presents the initial results of excavations at Kanjera South, located on the Homa Peninsula in Western Kenya. Since 1995, our exploration of this locality has yielded a combination of artefacts and well preserved faunal remains in a sedimentary context that also allows for environmental reconstruction. Here we examine the history of exploration of Kanjera and its significance in the development of palaeoanthropological research in East Africa. We also summarise our findings from the recently discovered Oldowan site. Taphonomic analyses suggest that the archaeological layers were formed at least partially by hominin activity. Artefacts made from a wide variety of raw materials are abundant, as are animal bones. Results of our first analyses confirm that Oldowan hominins had considerable behavioural flexibility and occupied a range of habitats.

Kolpochoerus heseloni is known from the later Pliocene into the middle Pleistocene of Africa. It is widely distributed in time and space, and it is known from many hominin palaeontological and archaeological sites in Africa. We use three methods to investigate the diet and habitat preferences of this species. Dental microwear analysis and carbon stable isotope analysis are used to examine diet, and limb bone ecomorphological analysis is used to reconstruct habitat preference. Results suggest that there is synchronic variability and change through time in the diet and habit preferences of K. heseloni. The results also reinforce how different this taxon is from extant pig species.

F aunal change at the Early-Middle Pleistocene boundary in Europe has long been a topic for discussion. However, analyses of large mammal turnover at this time in Africa have been lacking, largely because of the low number of sites dated to this interval. Recent work, particularly in the last 10 years, has resulted in a much larger published sample of sites and we synthesize these data in this paper. In our multivariate (TWINSPAN) analyses of African and Levantine large mammal faunas we found that localities were subdivided by geographic regions, not by age. There were some small-scale changes with the appearance or extinction of particular taxa, but there was no large-scale turnover such as that seen in Europe. The Levant was included as a possible route for faunal interchange with east Africa, but no similarities were found between these areas. It therefore appears that the modern zoogeographic separation of the Levant and north Africa into the Palaearctic region and sub-Saharan Africa into the African region can be traced back to at least the Early-Middle Pleistocene boundary.

One of the distinguishing features of Homo sapiens is its absolutely and relatively large brain. This feature is also seen in less extreme form in some fossil Homo species. However, are increases in brain size during the Plio-Pleistocene only seen in Homo, and is brain enlargement among Plio-Pleistocene primates confined to hominins? This study examines evidence for changes in brain size for species and lineage samples of three synchronic East African fossil primate groups, the two hominin genera Homo and Paranthropus, and the cercopithecoid genus Theropithecus. Hominin endocranial capacity data were taken from the literature, but it was necessary to develop an indirect method for estimating the endocranial volume of Theropithecus. Bivariate and multivariate regression equations relating measured endocranial volume to three external cranial dimensions were developed from a large (ca. 340) sample of modern African cercopithecoids. These equations were used to estimate the endocranial volumes of 20 Theropithecus specimens from the African Plio-Pleistocene. Spearman's rho and the Hubert nonparametric test were used to search for evidence of temporal trends in both the hominin and Theropithecus data. Endocranial volume apparently increased over time in both Homo and Paranthropus boisei, but there was no evidence for temporal trends in the endocranial volume of Theropithecus. Thus, hypotheses which suggest a mix of environmental, social, dietary, or other factors as catalysts for increasing brain in Plio-Pleistocene primates must accommodate evidence of brain enlargement in both Homo and Paranthropus, and explain why this phenomenon appears to be restricted to hominins.

The late Pliocene is notable for the appearance of two new hominid genera as well as the first archaeological sites, generally attributed to the Oldowan Industrial Complex. However, the behavioral ecology of Oldowan hominids has been little explored, particularly at sites older than 2.0 Ma. Moreover, debates on Oldowan hominid foraging ecology and behavior have centered on data from only two regions, and often from single site levels. Here we describe the preliminary results of our investigation of Oldowan occurrences at Kanjera South. These occurrences preserve the oldest known traces of hominid activity in southwestern Kenya, and unlike most of the Oldowan sites in the 2.0-2.5 Ma time interval, artefacts are found in spatial association with a well-preserved fauna. In 1996 and 1997, this project initiated the first excavation program for Kanjera South. Magneto- and biostratigraphy indicate that deposition began approximately 2.2 Ma, substantially earlier than previously thought. At Excavation 1, artefacts were found in spatial association with a taxonomically diverse faunal assemblage in Beds KS-1 and KS-2. Excavation 2 yielded a partial hippopotamus axial skeleton with artefacts in KS-3. Cores from both sites were incidentally flaked and represent a Mode I lithic technology indistinguishable from the Oldowan. Approximately 15% of the artefacts were manufactured from non-local raw materials, indicating a flow of resources into the area. Stable isotopic analysis of KS-1 and KS-2 pedogenic carbonates suggests that the Excavation 1 assemblages formed in a relatively open (>75% C4 grass) habitat. The Excavation 1 and 2 faunas contain a high proportion of equids relative to Oldowan accumulations from Bed I Olduvai Gorge, Tanzania. Beds KS-1 and KS-2 thus preserve traces of Oldowan hominid activities in a more open setting than has been previously documented.

The late Pliocene and Pleistocene sediments of the Homa Peninsula in southwestern Kenya are richly fossiliferous, preserve Early Stone Age archaeological traces and provide one of the few paleoanthropological data sets for the region between the branches of the East African Rift Valley. This paper presents preliminary results of our ongoing investigation of late Pliocene and Pleistocene deposits at the localities of Rawi, Kanam East, Kanam Central and Kanjera. While fossils have been collected from the peninsula since 1911, little systematic effort has been made to place them into a broader litho- and chronostratigraphic framework. This project has conclusively demonstrated that fossils occur in good stratigraphic context at all of the study localities and that claims of sediment slumping (Boswell, 1935) have been greatly overstated (Behrensmeyeret al., 1995; Plummer & Potts, 1989). A provisional chronostratigraphic framework based on magneto- and biostratigraphy is presented here. We have revised the Plio-Pleistocene stratigraphy of the Rawi and Kanam gullies to include three formations: the Rawi, Abundu and Kasibos Formations. Based on magneto- and biostratigraphy, these formations are dated between approximately three and one m.y.a. (Gauss Chron–Jaramillo Subchron) (Cande & Kent, 1995). The Apoko Formation unconformably overlies the others and may be middle to late Pleistocene in age. All formations contain rich patches of fossils, and Acheulean artifacts have been surface collected from the Abundu and Kasibos Formations. Deposition of the fossil- and artefact-bearing sediments at Kanjera North began in the early Pleistocene and continued into the middle Pleistocene. Deposition at Kanjera South began over one million years earlier than previously thought, at approximately 2·2 m.y.a., and continued into the Olduvai Subchron (1·770–1·950 m.y.a.; Cande & Kent, 1995). Excavations have recovered Oldowan artefacts in association with well-preserved fossil fauna near the base of the sequence, the oldest archaeological traces yet known from southwestern Kenya.

A review of the middle Pleistocene vertebrate faunas of Africa is presented. After a summary of the climate and conditions prevalent during the middle Pleistocene, a regional approach is taken to the evidence, focusing in turn on northern Africa, eastern Africa, and southern Africa. Western Africa is not discussed due to the lack of faunal remains from the region. The changes in geographic range of some species and the composition of the evolving African fauna are emphasized, and modern African terrestrial faunas are shown to be archaic in comparison with those of Eurasia and the Americas.

Les AA etudient la variabilite du comportement des hominides africains durant le Pleistocene moyen

We examine the relationship between mesowear variables and carbon and nitrogen isotopes in 16 species of African antelope (Mammalia: Bovidae). We show significant differences in carbon and nitrogen isotope values between individuals exhibiting sharp versus round cusps, and high versus low occlusal relief. We show significant correlations between mesowear variables and both carbon and nitrogen isotopes. We find significant correlations between mesowear score and nitrogen, but not carbon isotopes. Finally, we find no significant correlations between hypsodonty index and either isotope examined. Our results provide strong support for the use of mesowear variables in palaeodietary reconstructions of antelopes. Our results further suggest that for the antelopes examined here, mesowear signals are a direct result of diet, while hyposodonty may be the result of phylogenetic legacy.

General ecological theories have paid scant attention to the information preserved in the fossil record. However, in order for an ecological theory to be truly general, it must hold in any ecosystem at any point in time. Here, we make the case that all modern ecological theories should be tested in geological time. We explore some of the limitations of the fossil record when examined in light of modern ecology. While there are fundamental differences between the way modern ecosystems and fossil ones are studied, we demonstrate that comparisons between the two are not impossible. We present three major research areas where fossil information has been successfully used to inform modern ecological thought; namely community ecology, biogeography and extinction studies. These examples also serve to highlight ecological issues that could not have been conceived purely on the basis of modern data. We advocate a much stronger interaction between modern ecologists and paleontologists in addressing present and future ecological questions.

Bed I Olduvai Gorge, Tanzania has provided abundant fauna in both paleontological and archeological contexts. These have been used to reconstruct the general paleoecological setting of the sites as well as provide more specific inferences on hominid habitat use. Previous paleoecological studies utilizing the Olduvai fauna have been taxon-based, substituting the habitat preferences of modern taxa for those of their extinct relatives. Here we investigate the relationship between bovid metapodial functional anatomy and habitat preference using taxon-free discriminant function analyses. We develop discriminant function models linking metapodial morphology to three broadly-defined habitat categories (open, intermediate, closed) using modern bovids of known ecology. The models developed for complete, proximal and distal metapodials are then applied to metapodials from four Bed I archeological localities: DK I, FLK NN I, FLK I and FLK N I. Results support the presence of the drying trend previously noted from middle to upper Bed I. They contradict taxon-based studies of the Olduvai bovids, suggesting a higher proportion of intermediate and closed habitats. The results of this study do not support theories of hominid foraging based on the exploitation of a single habitat type. The bovids from each locality exhibit a range of morphologies, suggesting that hominids at Olduvai were utilizing habitats ranging from open to closed, perhaps the full range available in the lake margin zone.

We examined the fossil remains of antelope (Mammalia: Bovidae) postcrania recovered from the Upper Laetolil Beds and the overlying Upper Ndolanya Beds in northern Tanzania. We used analyses of the ecomorphology of extinct antelopes to determine their habitat preferences. The most common postcranial elements - the phalanges, astragali, and distal radii - were examined. A total sample of 446 specimens was analyzed. Changes in the relative proportion of habitat preferences through time are suggestive of temporal fluctuations in habitat availability. As has been noted elsewhere, the mammals from Laetoli do not show the expected distribution of body sizes, so this paper also examined how such size biases, assumed to be taphonomic in origin, might have affected the reconstructions proposed here. We conclude that, on the basis of habitat preferences of the antelopes recovered from Laetoli, there is evidence for the continuous regional presence of woodland and forest throughout deposition of the Upper Laetolil Beds. Antelopes preferring forest and heavy cover habitats dominate the assemblage. Antelopes that locomoted principally in open and light cover habitats are largely in the minority, with a combined frequency never exceeding around 25% of the total in each stratigraphic unit of the Upper Laetolil Beds. The relative proportions of heavy cover and forest preferring antelopes in particular are likely affected by body size biases caused by taphonomic processes active during the deposition of the Upper Laetolil Beds, which favoured the preservation of the postcrania of smaller antelopes. During the formation of the Upper Ndolanya Beds, the proportion of antelopes preferring more open habitats is greatly increased, although forest-preferring antelopes are still present. The conclusion that forest and woodland were always present throughout the sequence is robust.

The manufacture of stone tools and their use to access animal tissues by Pliocene hominins marks the origin of a key adaptation in human evolutionary history. Here we report an in situ archaeological assemblage from the Koobi Fora Formation in northern Kenya that provides a unique combination of faunal remains, some with direct evidence of butchery, and Oldowan artifacts, which are well dated to 1.95 Ma. This site provides the oldest in situ evidence that hominins, predating Homo erectus , enjoyed access to carcasses of terrestrial and aquatic animals that they butchered in a well-watered habitat. It also provides the earliest definitive evidence of the incorporation into the hominin diet of various aquatic animals including turtles, crocodiles, and fish, which are rich sources of specific nutrients needed in human brain growth. The evidence here shows that these critical brain-growth compounds were part of the diets of hominins before the appearance of Homo ergaster/erectus and could have played an important role in the evolution of larger brains in the early history of our lineage.

BACKGROUND: Major biological and cultural innovations in late Pliocene hominin evolution are frequently linked to the spread or fluctuating presence of C(4) grass in African ecosystems. Whereas the deep sea record of global climatic change provides indirect evidence for an increase in C(4) vegetation with a shift towards a cooler, drier and more variable global climatic regime beginning approximately 3 million years ago (Ma), evidence for grassland-dominated ecosystems in continental Africa and hominin activities within such ecosystems have been lacking. METHODOLOGY/PRINCIPAL FINDINGS: We report stable isotopic analyses of pedogenic carbonates and ungulate enamel, as well as faunal data from approximately 2.0 Ma archeological occurrences at Kanjera South, Kenya. These document repeated hominin activities within a grassland-dominated ecosystem. CONCLUSIONS/SIGNIFICANCE: These data demonstrate what hitherto had been speculated based on indirect evidence: that grassland-dominated ecosystems did in fact exist during the Plio-Pleistocene, and that early Homo was active in open settings. Comparison with other Oldowan occurrences indicates that by 2.0 Ma hominins, almost certainly of the genus Homo, used a broad spectrum of habitats in East Africa, from open grassland to riparian forest. This strongly contrasts with the habitat usage of Australopithecus, and may signal an important shift in hominin landscape usage.

Advances in the study of Oldowan research have suggested that the earliest tool-makers had the technological capabilities usually suggested in later time periods. Work in West Turkana and Gona research areas suggests that Pliocene hominins had a concise understanding of stone fracture mechanics and had a clear conception of how to reduce cores in a manner that maintained flaking surfaces. Here we investigate if these same patterns existed at the Pliocene site of Kanjera South in Western Kenya. Technological analyses suggest that although many of the technological capabilities described for other Oldowan sites are present in the Kanjera South assemblage, specific aspects of the context of the site (raw material variability) produced a different expression of these behaviors. The most obvious difference between the Kanjera South site and other Oldowan sites is that as reduction continues several different reduction patterns can be seen. This suggests that a reduction sequence or core reduction mode is not an immutable formula and can change depending on its context.

The earliest archaeological traces and two new hominin genera (Homo and Paranthropus) appear in the late Pliocene of Africa. These first appearances may reflect novel hominin adaptive responses to shifting resource bases over geological time and/or an increasingly seasonal distribution of food over the annual cycle. Whereas regional environmental change has been documented during the Plio-Pleistocene of East Africa, it is difficult to resolve relative proportions of specific habitats at a given place and time, how these may have changed over time, and the explicit nature of particular habitats. Detailed reconstructions of paleohabitats based on paleontological, geological and geochemical evidence are necessary in order to better understand the interplay between environmental change and hominin biological and behavioral evolution.

The Rawi Gully, located on the Homa Peninsula in southwestern Kenya, has produced several fossil elements of a large cercopithecid from sediments approximately 2.5 million years old (Ma). Nearly all of these elements appear to represent a single adult male individual of the colobine species Cercopithecoides kimeui Leakey, 1982. Part of the face, mandible, dentition, and several small postcranial fragments were collected by the Homa Peninsula Paleoanthropological Project (HPPP) in 1994 and 1995. This individual also appears to be represented by material collected in two previous expeditions to the site, one led by David Pilbeam in the 1970s and an earlier expedition led by L.S.B. Leakey in 1933. This specimen may extend the first appearance of C. kimeui by approximately 500 Kyr, and provides the first evidence for much of the male facial morphology in this species. Furthermore, Rawi may represent a more wooded habitat than the other occurrences of C. kimeui at Olduvai Gorge, Tanzania, and Koobi Fora, Kenya, indicating that C. kimeui may have been relatively flexible in its habitat preferences.

Reconstructions of the paleoenvironments of early hominids offer a framework for understanding hominid ecological and behavioral adaptations. Habitat reconstructions typically rely upon various biological or physical habitat indicators, and here we present reconstructions of the Plio-Pleistocene paleohabitats of Koobi Fora and Olduvai Gorge as based on fossil bovids (Artiodactyla: Bovidae). Bovids are the most common faunal element at most Neogene hominid and hominoid fossil localities and have been widely studied. This study addresses the functional morphology of the bovid femur through discriminant function analysis and provides additional support for the observation that certain features of the femur demonstrate clear correlations with the amount of vegetative cover in different modern habitats. The reconstructions for both Koobi Fora and Olduvai Gorge suggest that the full range of environments inhabited by living bovids was present during the Plio-Pleistocene. Koobi Fora appears to have had a somewhat higher percentage of more closed habitats than the relatively more open habitats of Olduvai Gorge. These habitat reconstructions are in broad agreement with other reconstructions based on a purely taxonomic approach to the bovid remains. Grounding our reconstructions of paleoenvironments in studies of functional morphology can help to develop a richer idea of the habitats and resources available to early hominids.

This contribution discusses suid specimens from the Manonga Valley, Tanzania. The 1990, 1992, and 1994 expeditions to the Wembere-Manonga Valley recovered 65 suid specimens from ten sites (Table I). Fossils suids derive from horizons throughout the Wembere-Manonga Formation, although the majority were recovered from the Ibole Member (Harrison 1991, 1993, 1994; Harrison and Verniers, 1993; Harrison et al., 1993; Haileab and Harrison, 1993; Mbago et al., 1993; Verniers, this volume, Chapter 2). There were no differences between specimens from the different members so they are treated together here. All suid remains can be attributed to the Pliocene species Nyanzachoerus kanamensis.

The appearance of Oldowan sites c. 2.5 million years ago signals one of the most important adaptive shifts in human evolution. Large mammal u butchery, stone artefact manufacture and novel transport and discard behaviours led to the accumulation of the first recognized archaeological debris. Although the earliest instances of these behaviours are 2.5 million years ago, most of what we know about Oldowan palaeoecology and behaviour is derived from localities more than half a million years younger, particularly c. 1.8 million-year-old sites from Bed I Olduvai Gorge, Tanzania (Potts 1988). Sites from Kanjera South, Homa Peninsula, southwestern Kenya, yield dense concentrations of artefacts in association with the oldest (c. 2.2 million years) substantial sample of archaeological fauna known thus far from Africa. This study is the first to use a wide range of traditional and innovative techniques to investigate Oldowan hominin behaviour and site formation processes before 2 million years ago.

A series of eight replication experiments tests the proposition that human trampling of stone flakes can produce edge damage that mimics deliberate retouch. Retouchlike edge damage, breakage, and other forms of macroscopic mechanical damage were observed on large numbers of pieces in all trampled sets. Experiments measured the relative contributions of three variables-raw material, artifact density, and substrate-in generating damage. Results indicate that while all three factors contribute to some degree, substrate plays the most decisive role, and that artifacts are more likely to exhibit damage if trampled on an impenetrable substrate. It was further found that trampling transforms flakes into pseudo-tools that can be classified as formal tools using a standard typology. Many of these are notched and denticulate pieces, indicating that special caution is needed in behavioral interpretations based on these tool types, and that the European Paleolithic Denticulate Mousterian industry requires critical reassessment.

Evidence of Oldowan tools by w2.6 million years ago (Ma) may signal a major adaptive shift in hominin \ud evolution. While tool-dependent butchery of large mammals was important by at least 2.0 Ma, the use of \ud artifacts for tasks other than faunal processing has been difficult to diagnose. Here we report on use-wear \ud analysis ofw2.0 Ma quartz and quartzite artifacts from Kanjera South, Kenya. A use-wear framework that \ud links processing of specific materials and tool motions to their resultant use-wear patterns was developed. \ud A blind test was then carried out to assess and improve the efficacy of this experimental use-wear \ud framework, which was then applied to the analysis of 62 Oldowan artifacts from Kanjera South. Usewear \ud on a total of 23 artifact edges was attributed to the processing of specific materials. Use-wear on \ud seven edges (30%) was attributed to animal tissue processing,corroborating zooarchaeological evidence \ud for butchery at the site. Use-wear on 16 edges (70%)was attributed to the processing of plant tissues, \ud including wood, grit-covered plant tissues that we interpret asunderground storage organs (USOs), and \ud stems of grass or sedges. These results expand our knowledge of the suite of behaviours carried out in the \ud vicinity of Kanjera South to include the processing of materials that would be ‘invisible’ using standard \ud archaeological methods. Wood cutting and scraping may represent the production and/or maintenance \ud of wooden tools. Use-wear related to USO processing extends the archaeological evidence for hominin acquisition and consumption of this resource by over 1.5 Ma. Cutting of grasses, sedges or reeds may be related to a subsistence task (e.g., grass seed harvesting, cutting out papyrus culm for consumption) and/or a non-subsistence related task (e.g., production of ‘twine,’ simple carrying devices, or bedding). These results highlight the adaptive significance of lithic technology for hominins at Kanjera.

The shift to increased meat consumption is one of the major adaptive changes in hominin dietary evolution. Although meat eating by Oldowan hominins is well evidenced at Pleistocene archaeological sites in eastern Africa by butchery marks on bones, the methods through which carcasses were acquired (i.e., hunting vs. scavenging) and extent of their completeness (fleshed vs. defleshed) is less certain. This study addresses these issues through a geographic information systems (GIS) comparative analysis of bone modification patterns created by hominins and carnivores observed in the ca. 2.0 Ma assemblage from Kanjera South, Kenya and those of several modern, experimentally modified bone assemblages. Comparison of GIS-generated models shows that the pattern of bone preservation at Kanjera South is similar to that found in experimental bone assemblages that were first butchered and hammerstone fractured by humans, and subsequently scavenged by carnivores. The distribution of bone modifications on the 2 Kanjera fauna also suggests hominins had early access to small bovids. Butchery marks appear almost exclusively in ‘hot zones’—areas where flesh does not typically survive lion consumption—further suggesting Kanjera hominins were not scavenging carnivore kills. Our findings support previous claims that the Kanjera assemblage offers the earliest clear evidence of repeated butchery of antelope carcasses by Early Stone Age ( Oldowan) hominins and perhaps the earliest evidence for hunting. Kanjera carnivore damage frequencies are lower than those reported for the slightly younger site of FLK Zinj (Olduvai Gorge, Tanzania), suggesting differing competitive regimes at the two sites.

Bone morphology of the cats (Mammalia: Felidae) is influenced by many factors, including locomotor mode, body size, hunting methods, prey size and phylogeny. Here, we investigate the shape of the proximal and distal humeral epiphyses in extant species of the felids, based on two-dimensional landmark configurations. Geometric morphometric techniques were used to describe shape differences in the context of phylogeny, allometry and locomotion. The influence of these factors on epiphyseal shape was assessed using Principal Component Analysis, Linear Discriminant functions and multivariate regression. Phylogenetic Generalised Least Squares was used to examine the association between size or locomotion and humeral epiphyseal shape, after taking a phylogenetic error term into account. Results show marked differences in epiphyseal shape between felid lineages, with a relatively large phylogenetic influence. Additionally, the adaptive influences of size and locomotion are demonstrated, and their influence is independent of phylogeny in most, but not all, cases. Several features of epiphyseal shape are common to the largest terrestrial felids, including a relative reduction in the surface area of the humeral head and increased robusticity of structures that provide attachment for joint-stabilising muscles, including the medial epicondyle and the greater and lesser tubercles. This increased robusticity is a functional response to the increased loading forces placed on the joints due to large body mass.

The Shungura Formation in the lower Omo River Valley, southern Ethiopia, has yielded an important paleontological and archeological record from the Pliocene and Pleistocene of eastern Africa. Fossils are common throughout the sequence and provide evidence of paleoenvironments and environmental change through time. This study developed discriminant function ecomorphology models that linked astragalus morphology to broadly defined habitat categories (open, light cover, heavy cover, forest, and wetlands) using modern bovids of known ecology. These models used seven variables suitable for use on fragmentary fossils and had overall classification success rates of >82%. Four hundred and one fossils were analyzed from Shungura Formation members B through G (3.4-1.9 million years ago). Analysis by member documented the full range of ecomorph categories, demonstrating that a wide range of habitats existed along the axis of the paleo-Omo River. Heavy cover ecomorphs, reflecting habitats such as woodland and heavy bushland, were the most common in the fossil sample. The trend of increasing open cover habitats from Members C through F suggested by other paleoenvironmental proxies was documented by the increase in open habitat ecomorphs during this interval. However, finer grained analysis demonstrated considerable variability in ecomorph frequencies over time, suggesting that substantial short-term variability is masked when grouping samples by member. The hominin genera Australopithecus, Homo, and Paranthropus are associated with a range of ecomorphs, indicating that all three genera were living in temporally variable and heterogeneous landscapes. Australopithecus finds were predominantly associated with lower frequencies of open habitat ecomorphs, and high frequencies of heavy cover ecomorphs, perhaps indicating a more woodland focus for this genus.

The past 5 million years mark a global change from the warmer, more stable climate of the Pliocene to the initiation of glacial–interglacial cycles during the Pleistocene. Marine core sediment records located off the coast of southwestern Africa indicate aridification and intensified upwelling in the Benguela Current over the Pliocene and Pleistocene. However, few terrestrial records document environmental change in southwestern Africa over this time interval. Here we synthesize new and published carbon and oxygen isotope data of the teeth from large mammals (> 6 kg) at Langebaanweg (~ 5 million years ago, Ma), Elandsfontein (1.0–0.6 Ma), and Hoedjiespunt (0.35–0.20 Ma), to evaluate environmental change in southwestern Africa between the Pliocene and Pleistocene. The majority of browsing and grazing herbivores from these sites yield enamel δ13C values within the range expected for animals with a pure C3 diet, however some taxa have enamel δ13C values that suggest the presence of small amounts C4 grasses at times during the Pleistocene. Considering that significant amounts of C4 grasses require a warm growing season, these results indicate that the winter rainfall zone, characteristic of the region today, could have been in place for the past 5 million years. The average δ18O value of the herbivore teeth increases ~ 4.4‰ between Langebaanweg and Elandsfontein for all taxa except suids. This increase may solely be a function of a change in hydrology between the fluvial system at Langebaanweg and the spring-fed environments at Elandsfontein, or a combination of factors that include depositional context, regional circulation and global climate. However, an increase in regional aridity or global cooling between the early Pliocene and mid-Pleistocene cannot explain the entire increase in enamel δ18O values. Spring-fed environments like those at Elandsfontein may have provided critical resources for mammalian fauna in the mid-Pleistocene within an increasingly arid southwestern Africa ecosystem.