Social and Behavioral Sciences Commons^™

A Nearly Complete Foot From Dikika, Ethiopia And Its Implications For The Ontogeny And Function Of Australopithecus Afarensis, Jeremy Desilva, Corey M. Gill, Thomas C. Prang, Miriam A. Bredella, Zeresenay Alemseged

Dartmouth Scholarship

The functional and evolutionary implications of primitive retentions in early hominin feet have been under debate since the discovery of Australopithecus afarensis. Ontogeny can provide insight into adult phenotypes, but juvenile early hominin foot fossils are exceptionally rare. We analyze a nearly complete, 3.32-million-year-old juvenile foot of A. afarensis (DIK-1-1f). We show that juvenile A. afarensis individuals already had many of the bipedal features found in adult specimens. However, they also had medial cuneiform traits associated with increased hallucal mobility and a more gracile calcaneal tuber, which is unexpected on the basis of known adult morphologies. Selection for traits …

A Nearly Complete Foot From Dikika, Ethiopia And Its Implications For The Ontogeny And Function Of Australopithecus Afarensis, Jeremy M. Desilva, Corey M. Gill, Thomas C. Prang, Miriam A. Bredella, Zeresenay Alemseged

Dartmouth Scholarship

The functional and evolutionary implications of primitive retentions in early hominin feet have been under debate since the discovery of Australopithecus afarensis. Ontogeny can provide insight into adult phenotypes, but juvenile early hominin foot fossils are exceptionally rare. We analyze a nearly complete, 3.32-million-year-old juvenile foot of A. afarensis (DIK-1-1f). We show that juvenile A. afarensis individuals already had many of the bipedal features found in adult specimens. However, they also had medial cuneiform traits associated with increased hallucal mobility and a more gracile calcaneal tuber, which is unexpected on the basis of known adult morphologies. Selection for traits …

Satellite Imagery-Based Monitoring Of Archaeological Site Damage In The Syrian Civil War, Jesse Casana, Elise Jakoby Laugier

Dartmouth Scholarship

Since the start of the Syrian civil war in 2011, the rich archaeological heritage of Syria and northern Iraq has faced severe threats, including looting, combat-related damage, and intentional demolition of monuments. However, the inaccessibility of the conflict zone to archaeologists or cultural heritage specialists has made it difficult to produce accurate damage assessments, impeding efforts to develop mitigation strategies and policies. This paper presents results of a project, undertaken in collaboration with the American Schools of Oriental Research (ASOR) and the US Department of State, to monitor damage to archaeological sites in Syria, northern Iraq, and southern Turkey using …

Hunter-Gatherer Residential Mobility And The Marginal Value Of Rainforest Patches, Vivek V. Venkataraman, Thomas S. Kraft, Nathaniel J. Dominy, Kirk M. Endicott

Dartmouth Scholarship

The residential mobility patterns of modern hunter-gatherers broadly reflect local resource availability, but the proximate ecological and social forces that determine the timing of camp movements are poorly known. We tested the hypothesis that the timing of such moves maximizes foraging efficiency as hunter-gatherers move across the landscape. The marginal value theorem predicts when a group should depart a camp and its associated foraging area and move to another based on declining marginal return rates. This influential model has yet to be directly applied in a population of hunter-gatherers, primarily because the shape of gain curves (cumulative resource acquisition through …

The Foot Of Homo Naledi, W. E.H Harcourt-Smith, Z. Throckmorton, K. A. Congdon, B. Zipfel, A. S. Deane, M. S.M. Drapeau, S. E. Churchill, L. R. Berger, J. M. Desilva

Dartmouth Scholarship

Modern humans are characterized by a highly specialized foot that reflects our obligate bipedalism. Our understanding of hominin foot evolution is, although, hindered by a paucity of well-associated remains. Here we describe the foot of Homo naledi from Dinaledi Chamber, South Africa, using 107 pedal elements, including one nearly-complete adult foot. The H. naledi foot is predominantly modern human-like in morphology and inferred function, with an adducted hallux, an elongated tarsus, and derived ankle and calcaneocuboid joints. In combination, these features indicate a foot well adapted for striding bipedalism. However, the H. naledi foot differs from modern humans in having …

Evidence For Patterns Of Selective Urban Migration In The Greater Indus Valley (2600-1900 Bc): A Lead And Strontium Isotope Mortuary Analysis, Benjamin Valentine, George D. Kamenov, Jonathan Mark Kenoyer, Vasant Shinde, Veena Mushrif-Tripathy, Erik Otarola-Castillo, John Krigbaum

Dartmouth Scholarship

Just as modern nation-states struggle to manage the cultural and economic impacts of migration, ancient civilizations dealt with similar external pressures and set policies to regulate people’s movements. In one of the earliest urban societies, the Indus Civilization, mechanisms linking city populations to hinterland groups remain enigmatic in the absence of written documents. However, isotopic data from human tooth enamel associated with Harappa Phase (2600-1900 BC) cemetery burials at Harappa (Pakistan) and Farmana (India) provide individual biogeochemical life histories of migration. Strontium and lead isotope ratios allow us to reinterpret the Indus tradition of cemetery inhumation as part of a …

Collapse Of An Ecological Network In Ancient Egypt, Justin Yeakel, Mathias Pires, Lars Rudolf, Nathaniel Dominy

Dartmouth Scholarship

The dynamics of ecosystem collapse are fundamental to determining how and why biological communities change through time, as well as the potential effects of extinctions on ecosystems. Here, we integrate depictions of mammals from Egyptian antiquity with direct lines of paleontological and archeological evidence to infer local extinctions and community dynamics over a 6,000-y span. The unprecedented temporal resolution of this dataset enables examination of how the tandem effects of human population growth and climate change can disrupt mammalian communities. We show that the extinctions of mammals in Egypt were nonrandom and that destabilizing changes in community composition coincided with …

The Impact Of Agricultural Emergence On The Genetic History Of African Rainforest Hunter-Gatherers And Agriculturalists, Etienne Patin, Katherine J. Siddle, Guillaume Laval, Hélène Quach, Christine Harmant, Noémie Becker, Alain Froment, Béatrice Régnault, Laure Lemée, Simon Gravel, Jean-Marie Hombert, Lolke Van Der Veen, Nathaniel J. Dominy, George H. Perry, Luis B. Barreiro, Paul Verdu, Evelyne Heyer, Lluís Quintana-Murci

Dartmouth Scholarship

The emergence of agriculture in West-Central Africa approximately 5,000 years ago, profoundly modified the cultural landscape and mode of subsistence of most sub-Saharan populations. How this major innovation has had an impact on the genetic history of rainforest hunter-gatherers—historically referred to as ‘pygmies’—and agriculturalists, however, remains poorly understood. Here we report genome-wide SNP data from these populations located west-to-east of the equatorial rainforest. We find that hunter-gathering populations present up to 50% of farmer genomic ancestry, and that substantial admixture began only within the last 1,000 years. Furthermore, we show that the historical population sizes characterizing these communities already differed …

Primate Energy Eexpenditure And Life History, Herman Pontzer, David A. Raichlen, Adam D. Gordon, Kara K. Schroepfer-Walker, Brian Hare, Matthew C. O’Neill, Kathleen M. Muldoon

Dartmouth Scholarship

Humans and other primates are distinct among placental mammals in having exceptionally slow rates of growth, reproduction, and aging. Primates’ slow life history schedules are generally thought to reflect an evolved strategy of allocating energy away from growth and reproduction and toward somatic investment, particularly to the development and maintenance of large brains. Here we examine an alternative explanation: that primates’ slow life histories reflect low total energy expenditure (TEE) (kilocalories per day) relative to other placental mammals. We compared doubly labeled water measurements of TEE among 17 primate species with similar measures for other placental mammals. We found that …

Colour And Odour Drive Fruit Selection And Seed Dispersal By Mouse Lemurs, Kim Valenta, Ryan J. Burke, Sarah A. Styler, Derek A. Jackson, Amanda D. Melin, Shawn M. Lehman

Dartmouth Scholarship

Animals and fruiting plants are involved in a complex set of interactions, with animals relying on fruiting trees as food resources, and fruiting trees relying on animals for seed dispersal. This interdependence shapes fruit signals such as colour and odour, to increase fruit detectability, and animal sensory systems, such as colour vision and olfaction to facilitate food identification and selection. Despite the ecological and evolutionary importance of plant-animal interactions for shaping animal sensory adaptations and plant characteristics, the details of the relationship are poorly understood. Here we examine the role of fruit chromaticity, luminance and odour on seed dispersal by …

Geographic Variation In Chin Shape Challenges The Universal Facial Attractiveness Hypothesis, Zaneta M. Thayer, Seth D. Dobson

Dartmouth Scholarship

The universal facial attractiveness (UFA) hypothesis proposes that some facial features are universally preferred because they are reliable signals of mate quality. The primary evidence for this hypothesis comes from cross-cultural studies of perceived attractiveness. However, these studies do not directly address patterns of morphological variation at the population level. An unanswered question is therefore: Are universally preferred facial phenotypes geographically invariant, as the UFA hypothesis implies? The purpose of our study is to evaluate this often overlooked aspect of the UFA hypothesis by examining patterns of geographic variation in chin shape. We collected symphyseal outlines from 180 recent human …

Tree Climbing And Human Evolution, Vivek V. Venkataraman, Thomas S. Kraft, Nathaniel J. Dominy

Dartmouth Scholarship

Paleoanthropologists have long argued—often contentiously—about the climbing abilities of early hominins and whether a foot adapted to terrestrial bipedalism constrained regular access to trees. However, some modern humans climb tall trees routinely in pursuit of honey, fruit, and game, often without the aid of tools or support systems. Mortality and morbidity associated with facultative arboreality is expected to favor behaviors and anatomies that facilitate safe and efficient climbing. Here we show that Twa hunter–gatherers use extraordinary ankle dorsiflexion (>45°) during climbing, similar to the degree observed in wild chimpanzees. Although we did not detect a skeletal signature of dorsiflexion …

The Climatic Niche Diversity Of Malagasy Primates: A Phylogenetic Perspective, Jason M. Kamilar, Kathleen M. Muldoon

Dartmouth Scholarship

Background:

Numerous researchers have posited that there should be a strong negative relationship between the evolutionary distance among species and their ecological similarity. Alternative evidence suggests that members of adaptive radiations should display no relationship between divergence time and ecological similarity because rapid evolution results in near-simultaneous speciation early in the clade's history. In this paper, we performed the first investigation of ecological diversity in a phylogenetic context using a mammalian adaptive radiation, the Malagasy primates.

Methodology/Principal Findings:

We collected data for 43 extant species including: 1) 1064 species by locality samples, 2) GIS climate data for each sampling locality, …

Evolutionism And Historical Particularism At The St. Petersburg Museum Of Anthropology And Ethnography, Sergei Kan

Dartmouth Scholarship

The paper describes the early 20th century debates between several leading Russian anthropologists, including Lev Shternberg, on the best way of displaying artifacts in the newly refurbished Museum of Anthropology and Ethnology in St. Petersburg. These debates revealed major tensions and contradictions between evolutionism and historical particularism, as well as universalism and nationalism within Russian anthropology of that era.