The Leakey Foundation

Whether the distribution of anatomically modem Homo sapiens was accomplished by a spread out of Africa late in time or by the continuous evolution of divergent regional lineages that interbred with each other is open to debate. Nowhere is this issue more contentious and less resolved than it is in East Asia. We know little about the appearance of the earliest anatomically modem humans in East Asia, and next to nothing about their pre-modem, “archaic” H. sapiens predecessors. The proposed research speaks to this problem in the most fundamental way, by furnishing a continuous archaeological and paleoenvironmental record from 120 – 40 kya, bridging the existing temporal gap between 100 and 40 kya. This is the logical first step to addressing the more difficult questions of behavior and biological identity during the proposed expansion of anatomically modem humans. The research is sited in the Western Loess Plateau of northwest China, which our previous research has shown contains a continuous and relatively fine-grained archaeological record dating back to about 120 kya. The region boasts deep stratigraphic exposures rich in Paleolithic remains datable by a combination of AMS radiocarbon and optically stimulated luminescence (OSL). With the continuous archaeological and paleoenvironmental sequence established by the proposed research, we can begin to address the potential for overlap, competition, or even admixture between the archaic occupants of East Asia and their modem successors.

Infraorbital morphology is commonly included in discussions of phylogenetic relationships within Homo, factoring prominently in debates regarding the evolutionary distinctiveness of H. sapiens and H. neanderthalensis (Trinkaus, 2006; Maddux and Franciscus, 2009), and cited as a key diagnostic feature of the controversial taxon H. antecessor (Bermúdez de Castro et al., 1997). However, the limited ability of traditional descriptive, qualitative and quantitative methods to accurately assess the complex morphology of the infraorbital region has led a number of researchers (e.g. Stringer, 2002; Rightmire, 2008) to question the reliability of infraorbital characters as phylogenetic indicators. Consequently, there is currently a need to more carefully evaluate the phylogenetic value of infraorbital morphology. Critical to this evaluation is the need to identify possible intercorrelations between infraorbital characters, and to determine whether these infraorbital characters scale allometrically. The proposed research will provide accurate quantification of infraorbital features (e.g. infraorbital surface topography, infraorbital orientation and zygomaticoalveolar crest curvature) in a large sample of Pleistocene and Holocene Homo, through the use of geometric morphometric methodologies specifically designed to quantify complex curvilinear structures. Once quantified, possible intercorrelations and allometric relationships will be determined, and the overall reliability of these infraorbital characters in phylogenetic analyses will be evaluated. This enhanced understanding of the phylogenetic relevance of infraorbital morphology will provide valuable contributions to the study of human origins, including elucidating the conceptual utility of “anatomical modernity” and the validity of H. antecessor as a hominin taxon.

Several cases of reciprocal services and transfers of goods among animals have been proposed as evidence for the occurrence of calculated reciprocity. Although unrelated animals may benefit from each other’s behavior, strong evidence about the mechanisms involved is still lacking. In this project, we aim at applying a comprehensive and comparative approach to test for some of the capacities that are required to perform reciprocal altruism. A first study will compare the ability of primates (from lemurs to chimpanzees) to delay gratification in a bartering task. The second study will explore the propensity of primates to exhibit risk-proneness or risk-aversion when bartering food item. Loss aversion and over-sensitivity to risk may indeed prevent to engage in bartering event. The last study will focus on the capacity of primates to reciprocate non edible item with a group member. Individuals will be given different tokens, one of them being exchangeable for food with a human experimenter, one being valuable for the partner, and one having no value. The trading of partner-valuable item will be analyzed in relation with social relationship between individuals. This research aims at understanding further how evolution may have shaped economic skills such as those observed in humans.

Unlike most other mammals humans cooperate in warfare, risking their lives in ways that benefit their social group at large. Using the theoretical literature on the evolution of cooperation in humans, I propose to examine the mechanisms that maintain cooperation among large numbers of unrelated individuals during warfare. I will address various hypotheses that have been proposed to explain cooperation in humans ranging from kin selection, misfiring of the kin psychology, costly-signaling, reputation and punishment, by examining warfare among the Turkana, a politically uncentralized subsistence pastoralist society in north-west Kenya. Large numbers of Turkana men, from various sub-sections of Turkana territory, are frequently mobilized for cattle-raiding and combat with neighboring pastoralist groups. I will use in-depth, semi-structured interviews with warriors, vignette studies and behavioral economic games to address these questions through multiple methods. Few empirical studies have focused on what stabilizes cooperation during warfare in small-scale societies. Such research can both help refine theoretical research on the evolution of large-scale cooperation, while also shedding new light on why humans engage in warfare at a scale that other mammalian species do not.

The earliest known stone artifacts are documented at Gona. The superior knapping skills, the high density of artifacts and the large number of 2.6 million year old (Ma) sites currently known at Gona is surprising for such an early age. The overall evidence points to hominid beginnings of the use of flaked-stones probably as early as 2.9 Ma, i.e. probably following the disappearance of A. afarensis. The lack of extensive fine-grained deposits between 2.9-2.6 Ma at Gona and elsewhere has left a major gap in the archaeological record. If hominids invented flaked-stones prior to 2.6 Ma, as already proposed by a number of researchers, such traces should be found at Gona. The research proposed here has a great potential to provide clues for the origins of hominid stone technology, which is among the primary goals of the Leakey Foundation. We plan to conduct systematic foot survey of some pockets of fine-grained sediments dated to 2.9-2.6 Ma at Gona to document possible archaeological traces to test if hominids used flaked-stones prior to 2.6 Ma. In addition, despite the large number of stone artifacts at 2.6 Ma, our knowledge of their function is limited to a few fragmentary bones recovered from Gona and Bouri. At Gona, the only complete cutmarked fossil dated to 2.6 Ma was found on the surface at OGS6, and excavations yielded a limited number of fossils. Thus far, OGS7 is the only site at Gona that has yielded 2.6 Ma associated artifacts and fossilized fauna (though fragmentary). Therefore, we propose to expand the excavation opened at OGS7 to recover artifacts and well-preserved associated fossilized bones for detailed understanding of the function of the oldest stone artifacts.

A taxonomic analysis of fossil birds excavated by the Olduvai Landscape Paleoanthropology Project (NISP = 2,200) and the available Leakey collections (NISP >800) from Bed I and Lower Bed II of Olduvai Gorge is proposed. It will be concurrent with the applicant’s ongoing taphonomic analysis of these fossils. Until now, the Olduvai birds have been greatly understudied, despite the extensive, long-term, interdisciplinary research focus at Olduvai and the intrinsic significance of this site to the study of human evolution. It is pertinent to the study of hominin paleoecology to understand the habitats in which hominins were active, and the faunal community with whom they interacted, yet currently the important avian component of the Oldowan faunal community at Olduvai is poorly known. Avian community composition can be linked to specific environmental parameters (e.g., water quality, vegetation cover, or prey species), such that knowledge of the taxonomic distribution of fossil bird occurrences across the paleolandscape can provide a unique and in-depth perspective on landscape heterogeneity and hominin land use at Olduvai. The taphonomic history of these assemblages must also be considered, since it can demonstrate potential bias in the composition and distribution of the fossil species. This work is strengthened by the applicant’s extensive neo-taphonomic and ecologic data on birds, derived from experimental and naturalistic studies in Tanzanian lake basins partially analogous to Olduvai during Bed I and Lower Bed II times. Data resulting from this coupling of taxonomic and taphonomic analysis will then be applied to current models of hominin land use and paleolandscape reconstructions at Olduvai, refining our understanding of Oldowan hominin paleoecology.

Primates possess highly varied color discrimination abilities. While some primate groups have evolved trichromatic color vision (catarrhines, platyrrhines, and some lemurs), others have lost color vision entirely (owl monkeys and lorisiforms). Furthermore, humans differ from other hominoids in the spectral sensitivity of their blue cones and have a higher frequency of color blindness relative to other primates. While many ecological factors have been examined in relation to the evolution of primate color vision, the role of variation in ambient light has only tentatively been explored. The intensity and spectral quality of ambient light differ dramatically between closed forests and more open habitats. The goal of this project is to test how variation in ambient light between habitats has influenced the evolution of primate color vision, using nocturnal lemurs as a model system. Ambient light will be measured over the lunar cycle (44 nights) in two lemur habitats in Madagascar: Ranomafana National Park (humid rainforest) and Kirindy Mitea National Park (dry deciduous forest). Genetic tests will be used to examine the history of selection acting on the S-opsin gene (coding for the blue cone) in 112 individuals from five nocturnal lemur genera endemic to these habitat types. By combining genetic and ecological approaches, this project will directly test how ambient light variation has influenced selection for color vision in primates. As such, this project has important implications for understanding the evolutionary context of primate and human visual systems. In particular, by testing the role of habitat variation in ambient light as a selective factor in visual evolution, this project will provide a framework of habitat transition for interpreting the unique features of human color vision.

Funding is requested for paleontological field work at Tabarin, a 4.42 Ma early hominin site in the Tugen Hills, Kenya. Recovered vertebrate fossils will be used in paleocommunity analyses to indicate the paleoenvironmental context(s) of early Pliocene hominins in the Tugen Hills. Microstratigraphic and sedimentologic studies will be used to help contextualize paleoenvironmental interpretations and identify taphonomic agents potentially affecting the assemblage. A “total collection” approach to fossil recovery will be utilized to minimize collector bias. The results of this study will be compared and contrasted with paleoenvironmental interpretations from penecontemporaneous Ethiopian hominin sites, ultimately providing a better understanding of variation (or lack thereof) in early hominin paleoenvironments.

This study will address the question of why the lateral toes in humans are so short compared to other primates. Short pedal phalanges are usually associated with cursoriality in digitigrades mammals, where they are thought to improve the mechanical advantage of the digital flexor muscles that support the body and generate propulsive forces at the end of stance. This study will test the hypothesis that shorter lateral toes in humans similarly improve locomotor performance by minimizing force, power and work outputs of the digital flexors at the metatarsophalangeal joints during bipedal locomotion. We will also test the alternative hypothesis that short lateral toes minimize the vertical motion of the leg required for foot clearance during the swing phase in walking. Using kinematic, force and plantar pressure data from a sample of humans representing normal variation in toe length, we will compare hindlimb kinematics and force, power and work outputs of the digital flexors during barefoot walking and running in individuals with short, average and long toes for their body mass. Results will provide important new information on the selective pressures that may have led to the derived forefoot morphology of humans. The study will also be the first to test whether short lateral toes were selected in the genus Homo to improve locomotor performance during endurance running. Finally, this study will create a normative dataset of plantar pressure in human locomotion, which will be useful for modelling forefoot function during locomotion in extinct hominins, and interpreting fossil footprints.

Objective: To assess the importance of color vision for primate frugivory. Research Questions: Are trichromatic monkeys more efficient than dichromatic monkeys at detecting the selecting fruit? Do foraging tasks or environmental conditions exist for which individuals of different phenotype are differentially suited? Can patterns of frugivory, alone or in conjunction with other foraging challenges, help explain the evolution and maintenance of polymorphic color vision in platyrrhine primates? What are the implications of this for the evolution of color vision and color vision deficiencies in human and non-human primates? Significance: Unlike other eutherian mammals, many primates have trichromatic vision. Interestingly, the expression of color vision is highly variable across the Order. While all catarrhine primates possess routine trichromacy, humans are unique among them in their high occurrence of color vision deficiencies. Further, most platyrrhine and some strepsirhine primates possess polymorphic color vision but routine trichromacy and monochromacy are also found in these primates. Since vision is a key sense to primates, understanding the adaptiveness of color vision provides insight into origins and evolution of humans and non-human primates. Methods: I will collect behavioral data on three groups of capuchins in Santa Rose National Park via focal animal sampling. The genotypes of each monkey will be determined via sequencing of fecal DNA. I will record three phenology measures and collect fruit and leaf samples for quantification of color and ripeness. Finally, I will use a spectrometer to measure the reflectance of food and background items as well as the irradiance of ambient light under different ecological conditions.

Due to a scarcity of fossil remains, mainland Southeast Asia has played a marginal role in models of human evolution and adaptation, despite its geographically-intermediate location. The goal of this research is to contribute to the paleoanthropological history of mainland Southeast Asia by initiating field work at Tam Hang, a cave site in northern Laos, that has previously yielded both Middle and Late Pleistocene fossils. The specific goals of this research project are to resume excavation of Late Pleistocene levels at Tam Hang; to create detailed mapping and survey of the study area to provide geological and geographical provenience of all fossil discoveries; and to survey the surrounding region for additional sites of interest for future field work. Most current models of Pleistocene hominin evolution suggest that Homo erectus is a late-surviving species in Asia. However because of the paucity of fossil material available from the majority of the Southeast Asian mainland, the marginal role of Asia in these models is based exclusively on the fossil evidence from China and Indonesia. Similarly, until recently, models of late Pleistocene human adaptation have been based solely on central and western Europe, despite the unique climate and landmass changes occurring in peninsular Southeast Asia. The proposed research will ultimately contribute fossil material from this under-represented region to test hypotheses about human evolution in Southeast Asia. A 28-day field season will include extensive survey, profile examinations and small scale excavation. We will begin with the Late Pleistocene layers of Tam Hang. In future excavations, we will continue to work at this site to uncover additional Middle Pleistocene layers.

Although dominance relations are known to be important among wild chimpanzees, they have never been shown to be related to food. intake. The objective of the present study is to quantify the effect of social dominance on diet quality and feeding behaviours among male chimpanzees in Kanyawara, Kibale National Park, Uganda. It is based on my recent discovery during my doctoral fieidwork that fruit density, fruit biomass, flesh density and flesh quality all vary vertically within individual trees as a function of light availability (Houle, 2003). I will test a new hypothesis, that variation in fruit micropatch quality explains the feeding advantages of dominance in wild chimpanzees.

In each observation-tree exploited by chimpanzees, I will first quantify the vertical stratification of light. Then, I will evaluate patch quality both within the whole tree crown and within micropatches, which will be predetermined vertical layers. Patch and micropatch quality will be assessed through the following variables: mass of individual fruit, individual fruit density, fruit pulp density, and biochemical analyses. Diet quality will be determined through the feeding rate (number of fruit put in the mouth per minute), the feeding cost (mean distance moved for one fruit put in the mouth), the relative feeding height (index varying from 0, the very bottom of a tree crown, to 1, the very top), and nutritional analyses. The inter-patch foraging cost the distance walked S between the patches- will also be measured (GIS). Finally, I will test the role of alliance on diet quality. Trees will be climbed after a modified version of the Single Rope Technique (Houle, 2002).

From the perspective of human origin and evolution, a sound evolutionary ecology of chimpanzee social organization is critical to understanding the evolution of human social organization from a chimpanzee-like ancestor.

The need to establish the chronological boundary between the demise of the Neanderthals, the makers of the Mousterian industries, and the first coloniZing Modern humans, in the Caucasus region was achieved in only one site. Here we proposed to continue the excavations of Dzudzuana cave in order to establish the dates for the late Middle Palaeolithic and early Upper Paleolithic in this region. The latest Neanderthals within their Eurasian territory survived specially in mountainous areas such as Gibraltar, Croatia, Crimea and the Caucasus. A recent joint project focused on the excavations of two sites: Dzudzuana Cave and Ortvale Klde rock shelter. The latter site provided a sequence of late Middle Paleolithic capped by Upper Paleolithic tool assemblage. The disappearance of the Neanderthals from Ortvale is well-dated to ca. 35/34 ka B.P. (uncalibrated). The first Upper Paleolithic in Dzudzuana are dates to ca. 32 Ka B.P.

However, Middle Paleolithic layers were not reached. Apparently, due to erosion they are missing from the frontal part of the cave.As all past excavations of caves in the region produced such Mousterian deposits, we believe that they are present inside the cave as indicated by a few artifacts. The difference in the hunted game between the two sites, which lie 5 km apart is reflected by the Caucasian tur that dominates the Ortvale Klde sequence while steppe bison, aurochs and Caucasian tur are the major prey species throughout the Upper Palaeolithic of Dzudzuana. Here we propose to excavate inside Dzudzuana cave, where we can obtain a large sample of animal bones, stone artifacts and sound dates and test the dates regarding the arrival of Modern humans in the Caucasus region.

Given the former rarity of Late Oligocene sites in Africa, evolutionary relationships among primates and other mammalian groups at that critical time have remained unclear. The description of two Late Oligocene faunas from Kenya (Losodok and Nakwai) in 2006 and the paleontological reconnaissance undertaken at these sites during June 2007 with funds awarded by the L.S.B. Leakey Foundation helped us to reformulate some long standing questions in African paleoanthropology. We recovered new, well preserved specimens of the ape-like catarrhine Kamoyapithecus hamiltoni, and remains of another anthropoid primate, similar to Propliopithecus from the Fayum. Several other mammalian groups were collected in 2007, increasing the sample size for already represented taxa, and adding new taxa. These sites offer the opportunity to fill in an important gap in our understanding of faunal dynamics in Africa during the middle part of the Tertiary, and provide an environmental context for the earliest ape-like catarrhine primates of East Africa. The fact that this fauna, the youngest Late Oligocene fauna of Africa, bears the stamp of archaic faunas and contains Kamoyapithecus makes it extremely relevant for the study of the origin and evolution of apes. This request appeals for funds that will allow me to assess taxonomic and ecomorphological changes during this critical interval by: 1) visiting relevant museums to collect data on diet, locomotion, and body mass, 2) conduct, as my doctoral dissertation project, the comparative analyses between this fauna and other African primate bearing localities of Early Oligocene and Early Miocene age, and 3) use these tools to understand the context in which hirge-bodied catarrhines evolved.

The external morphology of the hindfoot bones (distal tibia, talus, and calcaneus) have long been held as key indicators of habitual posture and locomotion in hominids. However, previous morphometric studies of some important fossil hindfoot bones reveal unique mosaics of ape-like and human-like features that complicate locomotor reconstruction of extinct hominins. This study will investigate whether the internal morphology of these bones (subchondral and trabecular bone) hold a diagnostic locomotor signal that may help to further characterize the nature of this mosaicism. From micro-computed tomography (µCT) images of associated hominid hindfoot bones this

study will quantify and concurrently examine subchondral and trabecular bone structural properties, both of which have been hypothesized to reflect the habitual compressive joint loads incurred during locomotion. To test these hypotheses, this study will first compare the pattern of these bone properties in modern human talocrural and subtalar joints to the contact area and articular pressure patterns that have been quantified in these joints from studies of simulated bipedal gait. Two archaeological human populations associated with different terrains (mountainous Machu Picchu, Peru and coastal Ancon, Peru) will also be examined to characterize intraspecific differences in these bone properties. Secondly, this study will assess whether these bone properties are consistent with current hypotheses of habitual hindfoot loads in hominids and can distinguish among species with different habitual locomotor behaviors. In doing so, this study will serve to mutually validate the use of subchondral and trabecular bone structural properties as tools to infer locomotor behavior from isolated skeletal elements. Finally, relevant to the mission of the Leakey Foundation, this study will provide a comparative sample with which to interpret the subchondral bone thickness and trabecular bone structure of fossil hominin hindfoot bones once µCT images are available, particularly those of AL 288-1, OH 8, Stw 573 and LB 1 whose functional morphologies are critical to our understanding of human evolution.

Do non-human primates provide care for physically disabled individuals? What are the implications for the evolution of conspecific care in humans? Recent debate about the inference of conspecific care in ancestral hominid relies on evidence from extant primates, yet little is known about conspecific care and physical disability in primates. A group of free-ranging Japanese macaques (Macaca fuscata) at the Awajishima Monkey Center (AMC) in Japan, presents a unique opportunity to investigate the relationships among physical impairment, behavior and physiology, in the context of congenital limb malformation in adult non-human primates. Specifically, I will collect data on

social and individual behavior, reproductive condition, infant care, and baseline fecal cortisol levels to examine their relationships to conspecific care and disability. I will collect behavioral and physiological data on disabled and nondisabled adult female Japanese macaques during three consecutive birth seasons (May-August 2005, 2006, and 2007) at the AMC, conducting behavioral data collection on 24 focal animals using 30-minutes continuous time samples. Fecal samples will be collected opportunistically and analyzed using enzyme immunoassay to assess cortisol concentrations. By combining physiological and behavioral measures, this study will contribute to understanding the consequences of physical impairment for free-ranging nonhuman primates and the origins of conspecific care in humans.

Cross-sectional properties are used extensively by paleoanthropologists to test hypotheses and make inferences about the mechanical loading history of hominin long bones. It is well-documented that long bone diaphyses respond adaptively to the loads imposed on them. However, genetics are also an important determinant of diaphyseal structural development, and genotype-specific patterns of bone growth should have predictable consequences for how sensitive a bone is to mechanical stimuli. If a particular genome contains information which instructs the cells to produce a stronger bone, that bone should be better designed to resist strains without triggering an osteogenic response. The magnitude of the functional signal in the diaphyses of individuals with identical activity patterns could therefore vary depending on their specific genetic background. If such an interaction between patterns of bone growth and mechanosensitivity exists, the use of cross sectional data for making intra- and intertaxonomic comparisons of hominin activity patterns may need to be reassessed. Indeed, there are indications. particularly from juvenile skeletal remains, that diaphyseal growth patterns varied widely among our hominin ancestors. The goal of this project is to use femoral cross-sectional data from three strains of inbred mice treated with voluntary exercise as a model system to test the null hypothesis that mechanically stimulated osteogenesis is independent of genotype-specific patterns of bone development. The diaphyseal growth patterns of these strains are unique and well-documented. A greater understanding of the relationship between genotype-specific patterns of bone growth and mechanosensitivity will then permit an assessment of reconstructions of ancient hominin activity patterns based on long bone cross-sectional data.

Vocal communication is a crucial social-cognitive component of primate behavior that is used to coordinate interactions among individuals cooperating and competing within social groups. The overall goal of this study is to explore comparatively how gorillas use vocal communication to socially adapt to their environment. Gorillas are particularly suitable for this investigation because they inhabit a diversity of habitats; however, everything we currently know about their vocal communication comes from a small population of mountain gorillas in the Virunga Volcanoes that is not a representation of the entire gorilla genus. The vocal behavior of Virunga mountain gorillas is characterized by the prevalent use of quiet vocalizations in unspecific contexts. Previous research suggested a number of hypotheses concerning their function, but these and additional hypotheses still need to be tested in other populations. This study will compare the vocal behavior of mountain gorillas (Gorilla beringei beringei) of Bwindi Impenetrable National Park, Uganda and Western gorillas (Gorilla gorilla gorilla) of Dzangha-Ndoki National Park, Central African Republic. This study is the first to describe the vocal repertoire of these gorilla populations and to test hypotheses concerning the function of particular vocalizations (double-grunts and “singing”). At both study sites I will compile a dataset on vocal behavior and related behavior with at least 30 hours of focal animal sampling per adult individual. During focal animal sampling, I will audio record vocal behavior as well as the context and behavioral consequences of the vocalizations. Understanding how primates use vocal communication to maintain their social relationships under different environmental conditions will contribute to our understanding of the evolution of language and sociality in primates and humans.

The origins of modem humans in Europe and the fate of the Neandertals are among the most hotly debated topics in paleoanthropology today. One view holds that Neandertals were somehow out-competed and replaced by anatomically modem humans moving into Europe between 40 and 30 thousand years ago (kya). In this scenario, Neandertals contribute little or nothing to the modem human gene pool or behavioral repertoire. The second argument supports a gradual transition with Neandertals and modem humans undergoing gene flow and acculturation. The early Upper Paleolithic of Europe is associated with the appearance of blade/bladelet technology (e.g. Aurignacian), including a wider range of fonnal tool types than seen in the Middle Paleolithic. Greater diversity in tool types is often interpreted as specialized tools created for specific tasks. This, in turn, is said to reflect dramatic behavioral shifts between Neandertals and modem humans. In order to test previous interpretations, one must understand early Upper Paleolithic stone tool function. Some of the earliest Upper Paleolithic sites in Europe, dating between 35-40,000 years ago, are in the Swabian Jura of southwestern Germany. To investigate stone tool function, microscopic residue and use-wear analyses (magnifications from 50-1000x) will be undertaken Aurignacian stone tools from the sites of Vogelherd, Hohle Fels and GeiBenlösterle in southwest Germany. Preliminary results from research conducted on these same sites in 2005 shows that residue preservation is excellent. An increased understanding of stone tool use will help elucidate the degree

of specialization and standardization of stone tool types in the Upper Paleolithic and can test hypotheses about behavioral differences between Neandertals and modem humans.

This project would improve the stratigraphic and geochronologic control for OlduvaiGorge Bed II, Tanzania, using tuffs. Bed II is poorly dated and correlation between sites is often uncertain. The relation between the Advanced Oldowan Band Acheulean technologies is particularly uncertain, as the former is found in the Olduvai “Junction” and the latter to the east and west. This could be explained by (a) differences in.raw material and tool function in different areas, (b) two separate, coexisting technologies, perhaps used by different species, or (c) a correlation problem between the Junction and outlying areas. I intend to sample Bed II tuffs from archaeological sites in east and west Olduvai for comparison to better-known Junction exposures. I will also sample tuffs at Peninj, a contemporaneous site 80 km north with better-dated tuffs. Tuffs are often used to establish stratigraphic frameworks and correlate between archaeological sites, however the conventional approach (composition of glass) is only applicable where tuffs are well preserved. Olduvai Bed II contains many tuffs, but most are altered, reworked, and, unevenly preserved. Using glass (where available) and phenocryst composition, I will identify geochemical fingerprints for each tuff and correlate between sites. In this study, I propose to (1) develop fingerprints for all Bed II and III tuffs, (2) create a detailed stratigraphic framework for Beds II and III by applying these fingerprints throughoutOlduvai, (3), place Developed Oldowan and Acheulean sites within this framework to determine their relative stratigraphic placement, (4), expand the geographic range of OLAPP’s time slice by identifying Tuff IIA over a broader area, and (5) determine ages for Bed II and III through 40Ar-39Ar dating of hornblende and correlation to dated tuffs at Peninj.

Among humans and other group-living taxa, competition among groups is shaped by similar pressures: limited access to food, mates, and other critical resources. There is a great deal of variation in the intergroup interactions (I GI s) of different species and sometimes even between populations, yet explanations for this diversity are locking. Although poorly understood, IGls affect individual reproductive success and possibly within-group social relationships; consequently, a thorough grasp of the factors underpinning IGI diversity will yield deeper insight into the relationships between ecology and social behavior. These insights are applicable to both extant and extinet taxa and will further our understanding of the evolutionary changes that occurred among the Homininae. Thus the objective of this study is to field test a novel model of intergroup conflict for group-living primates. The model predicts specific patterns of sex-specific participation in IGls based on the economic defendability of particular resources, and leads to different predictions for sympatric grey-cheeked mangabeys (Lophocebus albigena) and redtail monkeys (Cercopithecus ascanius). These predictions will be compared with the IGI regime of each species, which will be determined through behavioral observations and playback experiments of groups at the Ngogo research station in Kibale National Park, Uganda. The intergroup relationships of these two species are incompletely known due to a lack of research on redtails and because previous research on mangabeys focused on a very low-density population in which groups did not appear to experience resource limitation. Additionally, the defendability of food resources will be evaluated through quantification of spatial and temporal patterns of availability.

Though many authors espouse either the adaptive or non-adaptive nature of human gender and gender socialization with equal vehemence, the evolutionary history of most human and primate sex-typical behaviors is completely unknown. This question can only be answered using a broad comparative dataset of non-human primate sex-typical behaviors and the socialization processes that contribute to their development, but such a dataset does not exist. Although it has been demonstrated that social environment influences the development of sex-typical social behavior in many non-human primates, the particular processes of socialization remain poorly understood. The objective of this study is to compare male and female social development both intra- and inter-specifically in order to identify socialization processes likely to be involved in the producti6n of adult sex-typical behavior in two different non-human primate social systems in the wild. Since primate sex-role socialization processes are poorly understood, this investigation will compare two species of the least socially complex, most primitive, and fastest-developing of the gregarious primates-Lemur catta and Eulemur fulvus rufus. Observational data will be collected on infants, juveniles, and adults from free-ranging populations in southwestern Madagascar and will be used to identify species typical sex differences in adult behavior as well as patterns of social interaction that may contribute to their development. This study will be the first to investigate socialization processes contributing to the development of sex-typical behavior in a comparative sample of nonhuman primates. It will increase scientific understanding of human evolution and behavior by making an important first contribution to the comparative dataset needed to make data-based inferences about fossil hominin sex roles and to illuminate evolutionary questions regarding modern human gender and gender socialization.

Facial morphology features prominently in species identification and phylogenetic reconstructions of the human fossil record. However, its use remains controversial, as the evolutionary significance of facial features is not well-understood. This study seeks to gain an improved knowledge of the development, integration and variation of the human face in order to assess the validity of facial morphology in defining Pleistocene hominin taxa and its usefulness in phylogenetic reconstructions. Questions that will be addressed include: Are there population specific changes in facial shape during modern human ontogeny? Are facial traits developmentally integrated in modern humans? How do particular facial traits vary ontogenetically between individuals and populations of modern humans, and among Pleistocene hominins? Is the mid-Pleistocene Homo (H. heidelbergensis s.l.) facial form more variable than that of modern humans? Is the same true for H. neanderthalensis? Is there a phased time-sequential development of Neanderthal-like facial traits among European Pleistocene hominins? Is there a similar trend in Africa?

To answer these questions, I will use a novel semilandmark geometric morphometric method involving analysis of facial surfaces rather than just landmarks to quantify subtle facial features frequently used to define Pleistocene taxa. Patterns of adult and ontogenetic variation and co-variation of these features will be established within recent human geographic samples and used as a framework for interpreting the human fossil record. This approach for the first time enables the rigorous quantitative analysis of facial morphology and the evaluation of its evolutionary significance. This work will have important implications for our use of facial morphology in assessing the human fossil record and will help elucidate the evolutionary processes of the later stages of human evolution and modern human origins.

The sites of Nadaouiyeh Ain Askar and Hummal are key sites for the Levant Palaeolithic chronology as they both have long stratigraphic sequences that span the Lower and Middle Palaeolithic. They are also both embedded in travertine spring deposits thus allowing the use of TIMS U-series dating, which is considered to be precise and reliable. A new Chronology based on TIMS U-series would depend on fewer assumptions than ESR or luminescence dating, and would contribute new data to the discussion about the somewhat contested lower part of the Levant chronology. However, ESR, luminescence, and palaeomagnetic methods will also be applied to the older parts of the sequences that are found to lie beyond the time range of TIMS U-series, and at certain key horizons. This multichronometric approach would yield a better new chronology, because it would be built on several independent dating methods. This approach should help to determine if the apparent younger ages for the Lower Palaeolithic industries in Syria (relative to the Israeli sequence) are 1) real differences 2) technical problems with previous dating attempts or 3) a result of their time-transgressive nature in the region. The dating work will also contribute to questions of human origins. The recent discoveries of two hominid fossils in Nadaouiyeh Ain Askar link the lithic assemblages (technocomplexes) of the Acheulian to Home erectus and the Yabroudian to Home sapiens. These dates would provide an age estimate for the antiquity of Homo erectus and Home sapiens in the Levant. Our research addresses questions of human origins and Pleistocene archaeology, thus it is clearly in line with the stated purpose of the Leakey Foundation.

Forty-seven years ago Louis and Mary Leakey invited colleagues to describe the newly discovered hominids from Beds I and II, Olduvai Gorge (Leakey 1960, 1961a,b). Tobias completed the description and analysis of the “Zinjanthropus boisei” (OH 5) skull and teeth in 1967 and those of the of Homo habilis in 1991. The Olduvai hominid postcrania, however, including the type and paratype of Homo habilis have never been described. As for the postcranials, debate continues as to which of the fossils represent H.habilis and which sample Paranthropus boisei (for example see Moya-Sola et al., 2008). The very question of how to define Homo versus Australopithecus(Wood, 1999) rests, in great measure, on whether we place the Bed I fossils in the genus Homo or in Australopithecus. In addition to those who would vacate the taxon H. habilis by assigning the type, OH 7, to Paranthropus there are others who suggest that H. habilis contains at least two species of early hominin.

The proposed research will provide the first in-depth descriptive and functional morphological accounts of the Olduvai postcrania including, among others, OH 7, OH 8, OH 10, OH 35, & OH 48. This work will address a number of questions, principal among them: 1) what constitutes the holotype of Homo habilis, 2) which fossils should be included in the type and, 3) what do the postcranial remains tell us about the functional morphology and behavior of early Homo versus contemporary australopithecines.

With this research project, I seek to examine the skeletal correlates of knuckle walking manifested in the digital elements of great apes. This research will have direct implications for understanding the evolution of locomotion in the hominoid lineage. A comparative analysis of the pressures experienced by different parts of the manus throughout a walking bout will be investigated for chimpanzees, gorillas, orangutans, and macaques. The resulting pressure distribution data will be tested for significance of differences within and across taxonomic and locomotor groups, and the implications of these differences for variation in the internal and external structure of the digits will be explored. A combination of JlCT scanning and caliper measurements will be used to assess trabecular bone orientation and subchondral bone density, and degree of curvature,· shaft robusticity, and articular surface dimensions, respectively, of the manual elements. Based on biomechanical assessments, it is predicted that the dorsum of the middle phalanges of knuckle walkers, which are under considerable compressive force, should possess relatively denser trabecular bone than those of palmigrade or suspensory taxa. Whether or not a locomotor signal can be seen within either the middle or proximal phalanges individually or within a comparative relationship between these elements will be explored. Pressure data will be collected using an RS Scan 0.5 x 0.4m pressure mat for a minimum of five individuals per taxon. The skeletal measurements will be collected on the manual proximal and middle phalanges of digits II-V. A minimum of five individuals per taxa will included in the µCT scan analysis, while a minimum of twenty individuals will be included in the external measures.

My objective is to examine proposed benefits associated with female philopatry in an egalitarian primate species Colobus vellerosus. The following questions will be investigated: 1) is the occurrence of female dispersal associated with low food abundance, high feeding competition, or absence of male kin? 2) do females show kin bias in affiliative behaviors? 3) are larger coalitions of female kin better at defending food resources? 4) what is the importance of female kinship in the evolution of social relationships and dispersal patterns in egalitarian primates? I will address these questions by conducting focal follows of females (n=50), surveying habitat quality, and collecting fecal samples in seven groups of C. vellerosus at Boabeng-Fiema, Ghana. One underlying assumption regarding the evolution of female philopatry in egalitarian primates is that larger coalitions of female kin should be more successful in between-group contests over food. This assumption has not yet been empirically tested, and C. vellerosus affords a unique opportunity to do so because females of this species show facultative dispersal that likely results in between-group variation in genetic structure. Studies investigating within-species variation in social structure are important for reconstructing the evolution of human social structure as foraging societies show a flexible residency pattern. C. vellerosus might also be a particularly well-suited species for comparative studies with humans due to behavioral similarities with women in foraging societies (e.g. egalitarian relationships, infant handling, and infrequent coalitionary aggression). Studies investigating nepotism and the adaptive value of female philopatry in egalitarian species are rare, and my research will therefore make a significant contribution to the empirical dataset needed to evaluate the current models of social structure in human and non-human primates

In primates, male reproductive tenure can be very short. While high turnover among males certainly affects male reproduction, it can also affect female reproduction. For example, evidence from wild geladas (Theropithecus gelada) suggests that infanticide following male takeovers may be a significant threat for females with dependent offspring. Reproductive counterstrategies reported for other species include (1) spontaneous abortions to curtail investment in otherwise “doomed” offspring and (2) deceptive sexual swellings to mimic the signs of fertility even if a female is pregnant or lactating. However, despite several anecdotal accounts, such female reproductive strategies have yet to be documented in geladas. I propose to investigate the underlying physiology and adaptive function of several reproductive strategies in female geladas to answer the question: does intersexual conflict exist in geladas? My first objective is to describe the normative patterns of gelada reproduction in terms of ovarian hormones, sexual swellings, and female reproductive behavior. My second objective is to investigate the functional significance behind the physiology and reproductive behavior of females, particularly during the immediate aftermath of a male takeover. Under this objective, first I will determine whether infanticide is indeed a threat to female geladas (using “stress” hormones, glucocorticoids) and then I will examine whether females have developed counterstrategies as a result. The specific counterstrategies I will focus on will be spontaneous abortion, accelerated weaning, and deceptive sexual swellings. Many medical studies treat miscarriage as a pathology rather than a possible adaptation based on external stimuli. If high rates of human miscarriage could be understood in evolutionary terms, particularly with respect to contributing social factors, a more appropriate model of human miscarriage could be developed.

The Dogon of Mali, West Africa, have been the subject of a 20 year, longitudinal study of human evolutionary biology that was initiated by a seed grant from the Leakey Foundation in 1985. The Dogon are ideal for studying human origins because they retain many features that have characterized humans over our evolutionary past, including the absence of contraception, mild polygyny, and kinship as the basis for social organization. During their menses, Dogon women visit a menstrual hut, a custom that facilitates research on the biology of menstruation and menopause. Here I propose to investigate the life histories of Dogon women to test the relative strength of the mother hypothesis versus the grandmother hypothesis for the maintenance of menopause in this population. Although no single population can be taken as a model for ancestral human populations at the time menopause evolved, the combined weight of multiple, carefully designed studies of contemporary populations can provide significant insights. Specifically, I will ask the following questions: (1) Does a woman’s age at death affect the number of her surviving grandoffspring?, (2) After controlling for differences in fertility and offspring survival between women, does the effect of a woman’s age at death on the survival of her grandoffspring still persist?, and (3) Does parental and grandparental survival affect children’s growth in middle childhood (ages 7 to 13 years)? The sample will include 400 women and 1300 children, the latter are part of a longitudinal study of child growth and development and have been followed since infancy. Field methods will emphasize demographic interviews facilitated by existing pedigrees and anthropometric measurements.

The objective of this research endeavor is to bring a diverse group of researchers together to conduct comparative study on the exceptionally well-preserved Australopithecus afarensis juvenile skeleton DIK-1-1 (or Selam). Ten paleoanthropologists, most of whom will be assessing the fossils for the first time, will convene at the National Museum of Ethiopia in Addis Ababa for 6 days to examine, describe and measure the different skeletal parts in order to integrate research results and achieve holistic interpretations of various aspects of the preserved elements. Each researcher will address questions related to a specific skeletal element, while the group will tackle issues related to ontogeny and its effects on our interpretation of function and behavior by comparing and contrasting signals that are driven from different parts of the skeleton. One of the most important questions we will address is whether functionally and behaviorally relevant features are maintained throughout ontogeny. The outcome of this research will aid our understanding of the ontogenetic context of many highly debated questions pertaining to human origins, including bipedalism, brain formation rate, stature and body plan in early hominins. The basic methods used in the proposed work are mainly morphological and metric comparisons on the original fossils, which will also form the basis of all subsequent work. Casts, and CT images of diverse fossils as well as the originals of other A. afarensis fossils currently housed in the National Museum of Ethiopia will also be used. One of the greatest strengths of the proposed work is that researchers will have the opportunity to work together, with fossils in hand, which will facilitate discussion during this project as well as future collaborative research.

This project was deferred from the Spring 2010 cycle. It has been resubmitted with new pilot data.

In July 2009 we explored the archaeological potential of the Knersvlakte of Namaqualand, South Africa, a previously archaeologically undocumented region with a unique environment 265km N of Cape Town. During this 3-week field season, we tested three rockshelters and collected data on numerous Middle Stone Age (MSA) artifact scatters. Two shelters preserved rich Later Stone Age sequences, probably extending back only a few thousand years. The third shelter, Varsche River (VR) 003, yielded >13,000 MSA stone artifacts (some potentially representing the Howeisons Poort and Still Bay), bones, and ostrich eggshell. In five days of excavation, we tested only the upper one-third of the slope with two test units each ~1m deep. However, the site could potentially reach 8m deep, so much remains to be explored. We are now seeking funds for a 4-week field season focused on VR003, plus support for analysis. To facilitate comparisons, we are following standard excavation practices established at other Paleolithic sites and are analyzing the assemblages within the frameworks currently applied to contemporaneous southern African assemblages.

Continuing excavation of VR003 has considerable potential to contribute to our knowledge of MSA behavioral variation and therefore modern human origins, and thereby directly furthers the goals of the Leakey Foundation. Most specialists agree that behavioral innovations in Africa allowed the descendants of African populations to spread throughout the world beginning ~50,000 years ago. However, disagreement continues about what caused these innovations and the significance of their temporal and spatial patterning. Resolving these issues requires a better understanding of MSA technological and ecological variation and data from more sites of appropriate antiquity in Africa, particularly those with faunal preservation. VR003 offers such an opportunity.

Regular monitoring of known mountain gorillas (Gorilla beringei beringei) inhabiting the Virunga mountains of Rwanda and neighboring countries has been conducted almost continuously since Dian Fossey established thc Karisoke Research Center in 1967. Our major objectives are to: (I) recover the skeletons of approximately 85 deceased mountain gorillas from Rwanda, many of whom are known individuals and buried, and help build local capacity for their curation, long-term preservation and management at the Musee d’Histoire Naturelle, Maison Kandt in Kigali; and (2) conduct the first comprehensive life history investigation of mineralized tissues in a known group of African apes, with an emphasis on discerning effects of environment, stress and individual life histories on bone and tooth development and microanatomy. Histological thin-sections will be prepared and CPL microscopy images acquired from midshafts of six bone elements and bucco-lingual sections of permanent teeth from hemi-mandibles in a pilot sample of 10 individuals from known habituated groups. Specific research aims include (I) providing important primary information concerning bone and tooth development in wild mountain gorillas; (2) determining the chronology of accentuated enamel striae and lines of arrested growth in bone, and their correspondence with environmental factors and individual life history events recorded in associated behavioral and veterinary records. Because intimate life details are known and veterinary records are available upon death, relationships between bone and tooth microanatomy, stress, environment and specific life history events will be examined with unparalleled discerning. Results will have significant implications for efforts to reconstruct the life histories and environmental contexts of great apes and humans in paleontological settings.

Kandis Fossil Site (KFS) is new Pliocene site recently discovered on outskirts of Nairobi about 40 minutes drive south- west of the capital.The site is located on margins of the Ngong escarpment on eastern margins of the Rift Valley at 01.39077S and 36.72365E with elevation of 1746 meters. The site was recently dated to 2.77+-0.01 Ma for the capping tuff on top of sequence but further dating is required for lower fossil bearing horizons which could be older.. Almost all the fossils remains derive from fluvial sediments below the capping tuff and could be older than the date obtained. Two excavations carried out in 2010 revealed abundant fauna totaling 800 individuals represented by various body elements. The large fauna represents 11 taxa. Preliminary faunal assessment from lower horizons reveal similarity to late Pliocene fauna from L. Turkana and the Lower Omo Valley and to some extend Hadar hence suggesting an age older than 3 Ma.(Geraad pers. Com.). If the suggested new dates are corroborated, the site has potential for illuminating the diversity of highland biodiversity in relation to episodes of major faunal turn over reported in the Turkana Basina and further illuminate highland palaeoenvironment in late Pliocene. The new site could also have potential for hominin evolutionary study. Any fossil hominin recovered would thus extend the range of early hominins to highland habitats. Further, the site’s close proximity to Nairobi would be important for practical demonstration of palaeontological excavation and recovery of fossils to high school and colleges within the city and around. Students will have an opportunity to witness actual fieldwork research that would include excavation, recovery and documentation of new fossils.