Objectives: In subsistence populations, high physical activity is typically maintained throughout pregnancy. Market integration shifts activity patterns to resemble industrialized populations, with more time allocated to sedentary behavior. Daasanach semi-nomadic pastoralists living in northern Kenya face lifestyle heterogeneity due to the emergence of a market center.
View Article and Find Full Text PDFClimate change is triggering environmental mobility through chronic water problems and punctuated events. Thinking about moving locations, or "mobility ideation", is the precursor to migration intentionality and actual migration. Drawing on the embodiment construct, this study examines how the worst drought in recent history in the Horn of Africa affected water-related mobility ideation and, in turn, fingernail cortisol concentration (FCC), a chronic stress biomarker, among Daasanach semi-nomadic pastoralists in northern Kenya.
View Article and Find Full Text PDFThe histories of African crops remain poorly understood despite their contemporary importance. Integration of crops from western, eastern and northern Africa probably first occurred in the Great Lakes Region of eastern Africa; however, little is known about when and how these agricultural systems coalesced. This article presents archaeobotanical analyses from an approximately 9000-year archaeological sequence at Kakapel Rockshelter in western Kenya, comprising the largest and most extensively dated archaeobotanical record from the interior of equatorial eastern Africa.
View Article and Find Full Text PDFBackground: Pastoralists live in challenging environments, which may be accompanied by unique activity, energy, and water requirements.
Aim: Few studies have examined whether the demands of pastoralism contribute to differences in total energy expenditure (TEE) and water turnover (WT) compared to other lifestyles.
Subjects And Methods: Accelerometer-derived physical activity, doubly labelled water-derived TEE and WT, and anthropometric data were collected for 34 semi-nomadic Daasanach adults from three northern Kenyan communities with different levels of pastoralist activity.
Background And Objectives: Non-communicable disease risk and the epidemic of cardiometabolic diseases continue to grow across the expanding industrialized world. Probing the relationships between evolved human physiology and modern socioecological conditions is central to understanding this health crisis. Therefore, we investigated the relationships between increased market access, shifting subsistence patterns and cardiometabolic health indicators within Daasanach semi-nomadic pastoralists who vary in their engagement in traditional lifestyle and emerging market behaviors.
View Article and Find Full Text PDFThe urban peoples of the Swahili coast traded across eastern Africa and the Indian Ocean and were among the first practitioners of Islam among sub-Saharan people. The extent to which these early interactions between Africans and non-Africans were accompanied by genetic exchange remains unknown. Here we report ancient DNA data for 80 individuals from 6 medieval and early modern (AD 1250-1800) coastal towns and an inland town after AD 1650.
View Article and Find Full Text PDFThis article quantifies Daasanach water insecurity experiences in Northern Kenya, examines how water insecurity is associated with water borrowing and psychosocial stress, and evaluates if water borrowing mitigates the stress from water insecurity. Of 133 households interviewed in 7 communities, 94% were water insecure and 74.4% borrowed water three or more times in the prior month.
View Article and Find Full Text PDFObjectives: Investigations of early childhood growth among small-scale populations are essential for understanding human life history variation and enhancing the ability to serve such communities through global public health initiatives. This study characterizes early childhood growth trajectories and identifies differences in growth patterns relative to international references among Daasanach semi-nomadic pastoralist children living in a hot, arid region of northern Kenya.
Methods: A large sample of height and weight measures were collected from children (N = 1756; total observations = 4508; age = 0-5 years) between 2018 and 2020.
Unlabelled: Evaluating error that arises through the aggregation of data recorded by multiple observers is a key consideration in many metric and geometric morphometric analyses of stone tool shape. One of the most common approaches involves the convergence of observers for repeat trails on the same set of artefacts: however, this is logistically and financially challenging when collaborating internationally and/or at a large scale. We present and evaluate a unique alternative for testing inter-observer error, involving the development of 3D printed copies of a lithic reference collection for distribution among observers.
View Article and Find Full Text PDFObjective: Water plays a critical role in the production of food and preparation of nutritious meals, yet few studies have examined the relationship between water and food insecurity. The primary objective of this study, therefore, was to examine how experiences of household water insecurity (HWI) relate to experiences of household food insecurity (HFI) among a pastoralist population living in an arid, water-stressed region of northern Kenya.
Design: We implemented the twelve-item Household Water Insecurity Experiences (HWISE, range 0-36) Scale and the nine-item Household Food Insecurity Access Scale (HFIAS, range 0-27) in a cross-sectional survey to measure HWI and HFI, respectively.
Multiple lines of genetic and archaeological evidence suggest that there were major demographic changes in the terminal Late Pleistocene epoch and early Holocene epoch of sub-Saharan Africa. Inferences about this period are challenging to make because demographic shifts in the past 5,000 years have obscured the structures of more ancient populations. Here we present genome-wide ancient DNA data for six individuals from eastern and south-central Africa spanning the past approximately 18,000 years (doubling the time depth of sub-Saharan African ancient DNA), increase the data quality for 15 previously published ancient individuals and analyse these alongside data from 13 other published ancient individuals.
View Article and Find Full Text PDFObjectives: Thirst is an evolved central homeostatic feedback system that helps regulate body water for survival. Little research has examined how early development and exposure to extreme environments and water availability affect thirst perception, particularly outside Western settings. Therefore, we compared two indicators of perceived thirst (current thirst and pleasantness of drinking water) using visual scales among Tsimane' forager-horticulturalists in the hot-humid Bolivian Amazon and Daasanach agro-pastoralists in hot-arid Northern Kenya.
View Article and Find Full Text PDFThe antiquity and nature of coastal resource procurement is central to understanding human evolution and adaptations to complex environments. It has become increasingly apparent in global archaeological studies that the timing, characteristics, and trajectories of coastal resource use are highly variable. Within Africa, discussions of these issues have largely been based on the archaeological record from the south and northeast of the continent, with little evidence from eastern coastal areas leaving significant spatial and temporal gaps in our knowledge.
View Article and Find Full Text PDFAssessing past foodways, subsistence strategies, and environments depends on the accurate identification of animals in the archaeological record. The high rates of fragmentation and often poor preservation of animal bones at many archaeological sites across sub-Saharan Africa have rendered archaeofaunal specimens unidentifiable beyond broad categories, such as "large mammal" or "medium bovid". Identification of archaeofaunal specimens through Zooarchaeology by Mass Spectrometry (ZooMS), or peptide mass fingerprinting of bone collagen, offers an avenue for identification of morphologically ambiguous or unidentifiable bone fragments from such assemblages.
View Article and Find Full Text PDFThe origin and evolution of hominin mortuary practices are topics of intense interest and debate. Human burials dated to the Middle Stone Age (MSA) are exceedingly rare in Africa and unknown in East Africa. Here we describe the partial skeleton of a roughly 2.
View Article and Find Full Text PDFIn the 12,000 years preceding the Industrial Revolution, human activities led to significant changes in land cover, plant and animal distributions, surface hydrology, and biochemical cycles. Earth system models suggest that this anthropogenic land cover change influenced regional and global climate. However, the representation of past land use in earth system models is currently oversimplified.
View Article and Find Full Text PDFThe KNM-ER 2598 occipital is among the oldest fossils attributed to Homo erectus but questions have been raised about whether it may derive from a younger horizon. Here we report on efforts to relocate the KNM-ER 2598 locality and investigate its paleontological and geological context. Although located in a different East Turkana collection area (Area 13) than initially reported, the locality is stratigraphically positioned below the KBS Tuff and the outcrops show no evidence of deflation of a younger unit, supporting an age of >1.
View Article and Find Full Text PDFThe Middle to Later Stone Age transition is a critical period of human behavioral change that has been variously argued to pertain to the emergence of modern cognition, substantial population growth, and major dispersals of Homo sapiens within and beyond Africa. However, there is little consensus about when the transition occurred, the geographic patterning of its emergence, or even how it is manifested in the stone tool technology that is used to define it. Here, we examine a long sequence of lithic technological change at the cave site of Panga ya Saidi, Kenya, that spans the Middle and Later Stone Age and includes human occupations in each of the last five Marine Isotope Stages.
View Article and Find Full Text PDFObjectives: The Late Pleistocene and early Holocene in eastern Africa are associated with complex evolutionary and demographic processes that contributed to the population variability observed in the region today. However, there are relatively few human skeletal remains from this time period. Here we describe six individuals from the Kisese II rockshelter in Tanzania that were excavated in 1956, present a radiocarbon date for one of the individuals, and compare craniodental morphological diversity among eastern African populations.
View Article and Find Full Text PDFWater salinity is a growing global environmental health concern. However, little is known about the relation between water salinity and chronic health outcomes in non-coastal, lean populations. Daasanach pastoralists living in northern Kenya traditionally rely on milk, yet are experiencing socioecological changes and have expressed concerns about the saltiness of their drinking water.
View Article and Find Full Text PDFConsuming the milk of other species is a unique adaptation of Homo sapiens, with implications for health, birth spacing and evolution. Key questions nonetheless remain regarding the origins of dairying and its relationship to the genetically-determined ability to drink milk into adulthood through lactase persistence (LP). As a major centre of LP diversity, Africa is of significant interest to the evolution of dairying.
View Article and Find Full Text PDFObjectives: This study compared the prevalence of concentrated urine (urine specific gravity ≥1.021), an indicator of hypohydration, across Tsimane' hunter-forager-horticulturalists living in hot-humid lowland Bolivia and Daasanach agropastoralists living in hot-arid Northern Kenya. It tested the hypotheses that household water and food insecurity would be associated with higher odds of hypohydration.
View Article and Find Full Text PDFAfrican Middle Stone Age (MSA) populations used pigments, manufactured and wore personal ornaments, made abstract engravings, and produced fully shaped bone tools. However, ongoing research across Africa reveals variability in the emergence of cultural innovations in the MSA and their subsequent development through the Later Stone Age (LSA). When present, it appears that cultural innovations manifest regional variability, suggestive of distinct cultural traditions.
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