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Taxonomic classification is important for understanding the natural world, yet current methods for species assessment often focus on craniodental morphology rather than the entire skeleton. Moreover, it is currently unknown how much variation could, or should, exist intragenerically. Here, we tested whether taxonomy can be accurately predicted based on patterns of morphological variation in macaques (H 1 ) and whether postcranial bones reflect subgeneric macaque taxonomy similarly, or better, than the cranium (H 2 ). Data included 3D scans of cranial and postcranial bones for eight macaque species (Macaca arctoides, Macaca fascicularis, Macaca fuscata, Macaca mulatta, Macaca nemestrina, Macaca nigra, Macaca radiata, and Macaca sylvanus). Fixed anatomical and semilandmarks were applied to scans of eight skeletal elements (crania = 45; mandible = 31; scapula = 66; humerus = 38; radius = 33; os coxa = 28; femur = 40; tibia = 40). For each skeletal element, regression analyses were performed to minimize the effects of sexual dimorphism. Between-groups principal components analysis was used to visualize the major patterns of among-species morphological variation, while the strength of correct taxon classification was measured with discriminant function analysis. Results suggested accepting the alternate hypothesis that different macaque species can be distinguished morphologically. Both cranial and many postcranial elements appeared to possess a taxonomic signal, and the limb bones-especially the upper limb-are reported to be more useful for taxonomic assessment than previously realized. Theoretically, certain behaviors and/or ecogeographical factors, as well as phylogeny, influenced skeletal morphology in macaques, likely contributing to taxonomic distinctions among different species., (© 2023 The Authors. The Anatomical Record published by Wiley Periodicals LLC on behalf of American Association for Anatomy.)

The question of how complex morphologies evolve, given constraints imposed by genetic, developmental and functional factors, has been a topic of inquiry for many decades. In the mid-twentieth century the study of morphological trait covariation, and the implications of this for evolutionary diversification, was developed under the general concept of "morphological integration". Given the polygenic inheritance model underlying quantitative skeletal traits, and the existence of differential pleiotropic effects, it is assumed that variation in the genotype to phenotype map will lead to the emergence of semi-autonomous "modules" that share relatively stronger covariance (integration) among traits within them. Understanding these potential patterns of modularity in the primate skeleton is important for clarifying the seeming inconsistencies presented by "mosaic" morphologies found in fossil taxa, as well as providing hypothetical units of morphological evolution that can be compared across the primate order. A review of the primate skeletal integration and modularity literature was conducted with the aim of assessing (i) the general nature of primate skeletal integration patterns, and (ii) the extent to which any identified modularity patterns are ubiquitous across primates. The vast literature on cranial integration reveals some consistency in suggesting that the face and the neurocranium (and in some cases, the basicranium and vault) form distinct modules, but the intensity of this modular pattern varies across taxa. The much more modest postcranial integration literature suggests that apes show overall reduced covariation among skeletal regions compared with other anthropoid taxa, but the extent to which any identified modularity patterns hold true across primates is still very unclear. While much has been learned about primate skeletal integration in the past two decades, we still need more studies that establish benchmarks as to what constitutes an integrated modular structure, and that empirically test these potential modules across a wider range of primate taxa.

Previous research has found that hominoids have stronger modularity between limb elements than other anthropoids, suggesting that there is less constraint on morphological diversification (e.g., limb proportions) in hominoids in terms of evolutionary independence. However, degrees of modularity in the axial skeleton have not been investigated across a broad range of anthropoid taxa. Thus, it is unknown whether hominoids also have stronger modularity in the axial skeleton than other anthropoids, which has implications for the evolution of diverse torso morphologies in Miocene apes as well as the evolution of novel characteristics in the skull and vertebrae of fossil hominins. In this study, 12 anthropoid genera were sampled to examine degrees of modularity between axial skeletal elements (i.e., cranium, mandible, vertebrae, and sacrum). Covariance ratio coefficients were calculated using variance/covariance matrices of interlandmark distances for each axial skeletal element to evaluate degrees of modularity. The results showed that Alouatta, Hylobates, Gorilla, Pan, and Homo showed generally stronger modularity than other anthropoid taxa when considering all axial skeletal elements. When only considering the vertebral elements (i.e., vertebrae and sacrum), Alouatta, Hylobates, Gorilla, and Pan showed generally stronger modularity than other anthropoid taxa. Humans showed stronger modularity between the skull and vertebrae than other hominoids. Thus, the evolution of novel characteristics in the skull and vertebral column may have been less constrained in fossil hominins due to the dissociation of trait covariation between axial skeletal elements in hominoid ancestors, thus fostering more evolutionary independence between the skull and vertebral column., Competing Interests: Declaration of competing interest None., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Previous research has suggested that magnitudes of integration may be distinct in the postcranium of hominoids when compared to other primate species. To test this hypothesis, we estimated and compared magnitudes of integration of eight postcranial bones from three-dimensional surface scans for 57 Hylobates lar, 58 Gorilla gorilla, 60 Pan troglodytes, 60 Homo sapiens, 60 Chlorocebus pygerythrus, and 60 Macaca fascicularis. We tested the hypotheses that 1) magnitudes of integration would be distinct in the postcranium of hominoids compared to cercopithecoids, with the explicit prediction that magnitudes of integration would be lower in hominoids than in cercopithecoids, and 2) girdle elements (scapula, os coxa) would have lower magnitudes of integration across all taxa. Integration was quantified using the integration coefficient of variation from interlandmark distances reflecting anatomical and developmental modules defined according to a priori criteria. A resampling protocol was employed to generate distributions of integration values that were then compared statistically using Mann-Whitney U tests with Bonferroni adjustment. Support for hypothesis 1 was mixed: with the exception of Gorilla, hominoid taxa were less integrated than the cercopithecoids for all anatomical modules. However, Homo, Gorilla, and, to a lesser extent, Pan showed higher integration than Hylobates and the cercopithecoids for homologous limb elements, with magnitudes of integration for both modules being lowest for Hylobates. These results generally support the hypothesis of distinct patterns of magnitudes of integration in the hominoid postcranium. The high integration of Gorilla may be explained by the effects of overall body size. The results supported the predictions of the second hypothesis. Regardless of taxon, the os coxa and scapula were generally the least integrated skeletal elements, while the femur and radius were the most integrated. The lower integration of the girdle elements suggests that the geometric complexities of particular elements may significantly influence study outcomes., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Human culture, biology, and health were shaped dramatically by the onset of agriculture ∼12,000 y B.P. This shift is hypothesized to have resulted in increased individual fitness and population growth as evidenced by archaeological and population genomic data alongside a decline in physiological health as inferred from skeletal remains. Here, we consider osteological and ancient DNA data from the same prehistoric individuals to study human stature variation as a proxy for health across a transition to agriculture. Specifically, we compared “predicted” genetic contributions to height from paleogenomic data and “achieved” adult osteological height estimated from long bone measurements for 167 individuals across Europe spanning the Upper Paleolithic to Iron Age (∼38,000 to 2,400 B.P.). We found that individuals from the Neolithic were shorter than expected (given their individual polygenic height scores) by an average of −3.82 cm relative to individuals from the Upper Paleolithic and Mesolithic (P = 0.040) and −2.21 cm shorter relative to post-Neolithic individuals (P = 0.068), with osteological vs. expected stature steadily increasing across the Copper (+1.95 cm relative to the Neolithic), Bronze (+2.70 cm), and Iron (+3.27 cm) Ages. These results were attenuated when we additionally accounted for genome-wide genetic ancestry variation: for example, with Neolithic individuals −2.82 cm shorter than expected on average relative to pre-Neolithic individuals (P = 0.120). We also incorporated observations of paleopathological indicators of nonspecific stress that can persist from childhood to adulthood in skeletal remains into our model. Overall, our work highlights the potential of integrating disparate datasets to explore proxies of health in prehistory.

The evolution of novel vertebral morphologies observed in humans and other extant hominoids may be related to changes in the magnitudes and/or patterns of covariation among traits. To examine this, we tested magnitudes of integration in the vertebral column of cercopithecoids and hominoids, including humans. Three-dimensional surface scans of 14 vertebral elements from 30 Cercopithecus, 32 Chlorocebus, 39 Macaca, 45 Hylobates, 31 Pan, and 86 Homo specimens were used. A resampling method was used to generate distributions of integration coefficient of variation scores for vertebral elements individually using interlandmark distances. Interspecific comparisons of mean integration coefficient of variation were conducted using Mann-Whitney U tests with Bonferroni adjustment. The results showed that hominoids generally had lower mean integration coefficient of variation than cercopithecoids. In addition, humans showed lower mean integration coefficient of variation than other hominoids in their last thoracic and lumbar vertebrae. Cercopithecoids and Hylobates showed relatively lower mean integration coefficient of variation in cervical vertebrae than in thoracolumbar vertebrae. Pan and Homo showed relatively lower mean integration coefficient of variation in the last thoracic and lumbar vertebrae in the thoracolumbar region, except for the L1 of Pan. The results suggest fewer integration-mediated constraints on the evolution of vertebral morphology in hominoids when compared with cercopithecoids. The weaker magnitudes of integration in lumbar vertebrae in humans when compared with chimpanzees likewise suggest fewer constraints on the evolution of novel lumbar vertebrae morphology in humans., Competing Interests: Declaration of competing interest None., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objectives: Magnitudes of morphological integration may constrain or facilitate craniofacial shape variation. The aim of this study was to analyze how the magnitude of integration in the skull of Macaca fascicularis changes throughout ontogeny in relation to developmental and/or functional modules., Materials and Methods: Geometric morphometric methods were used to analyze the magnitude of integration in the macaque cranium and mandible in 80 juvenile and 40 adult M. fascicularis specimens. Integration scores in skull modules were calculated using integration coefficient of variation (ICV) of eigenvalues based on a resampling procedure. Resultant ICV scores between the skull as a whole, and developmental and/or functional modules were compared using Mann-Whitney U tests., Results: Results showed that most skull modules were more tightly integrated than the skull as a whole, with the exception of the chondrocranium in juveniles without canines, the chondrocranium/face complex and the mandibular corpus in adults, and the mandibular ramus in all juveniles. The chondrocranium/face and face/mandibular corpus complexes were more tightly integrated in juveniles than adults, possibly reflecting the influences of early brain growth/development, and the changing functional demands of infant suckling and later masticatory loading. This is also supported by the much higher integration of the mandibular ramus in adults compared with juveniles., Discussion: Magnitudes of integration in skull modules reflect developmental/functional mechanisms in M. fascicularis. However, the relationship between "evolutionary flexibility" and developmental/functional mechanisms was not direct or simple, likely because of the complex morphology, multifunctionality, and various ossification origins of the skull., (© 2020 Wiley Periodicals LLC.)

Objectives: The cranium is generally considered more reliable than the postcranium for assessing primate taxonomy, although recent research suggests that pelvic shape may be equally reliable. However, little research has focused on intrageneric taxonomic discrimination. Here, we test the relative taxonomic efficacy of the cranium and os coxa for differentiating two macaque species, with and without considering sexual dimorphism., Materials and Methods: Geometric morphometric analyses were performed on cranial and os coxa landmarks for 119 adult Macaca fascicularis, M. mulatta, and Chlorocebus pygerythrus. Among-group shape variation was examined using canonical variates analyses. Cross-validated discriminant function analysis provided rates of correct group classification. Additionally, average morphological distances were compared with neutral genetic distances., Results: Macaque species were clearly differentiated, both cranially and pelvically, when sex was not considered. Males were more often correctly classified based on the os coxa, while female classification rates were high for both morphologies. Female crania and male os coxa were differentiated approximately the same as genetic distance, while male crania were more similar (convergent), and female os coxa were more divergent than expected based on genetic distance., Discussion: The hypothesis that cranial and os coxal shape can be used to discriminate among macaque species was supported. The cranium was better at differentiating females, while the os coxa was better at differentiating male macaques. Hence, there is no a priori reason for preferring the cranium when assessing intragenetic taxonomic relationships, but the effects of high levels of sexual dimorphism must be corrected for to accurately assess taxonomic signatures., (© 2020 Wiley Periodicals LLC.)

Objectives: Written accounts, as well as a previous craniometric study, indicate that migrations of non-Europeans and conversions of Europeans to Islam define Ottoman communities in Early Modern Europe. What is less clear are the roles of migration and admixture in generating intra-communal variation. This study combines craniometric with strontium isotope data to compare the cranial affinities of locally born and immigrant individuals. We predict that locally born individuals are more likely than non-locals to show evidence of admixture., Materials and Methods: Radiogenic strontium isotope data for 21 Ottomans were compared against archaeological faunal values. Sixteen individuals with intact crania were also measured and compared against two comparative source populations from Anatolia and Europe. Discriminant function analysis assigned unclassified Ottoans to either comparative group based on typicality probabilities, with potential admixture established via intermediate morphology between the two source populations., Results: Strontium isotope values revealed relatively high proportions of non-locals, consistent with high mobility documented historically. The sexes differed, with more males classifying as "typically Anatolian" than females. Locals and non-locals also had different cranial affinity patterns, with most classifying either as "typically Anatolian" or "typically European." Contrary to expectation, none of the locals were identified as intermediate, suggesting admixture rates were relatively low., Conclusions: Consistent with historical records, the results revealed high levels of extra-regional migration, with most individuals identifiable as either typically Anatolian or European. Moreover, locals and non-locals differed craniometrically, with no signs of admixture between Anatolian migrants and European converts in locals. This suggests intra-communal divisions were maintained., (© 2020 Wiley Periodicals, Inc.)

The human settlement of the Americas has been a topic of intense debate for centuries, and there is still no consensus on the tempo and mode of early human dispersion across the continent. When trying to explain the biological diversity of early groups across North, Central and South America, studies have defended a wide range of dispersion models that tend to oversimplify the diversity observed across the continent. In this study, we aim to contribute to this debate by exploring the cranial morphological affinities of four late Pleistocene/early Holocene specimens recovered from the caves of Quintana Roo, Mexico. The four specimens are among the earliest human remains known in the continent and permit the contextualization of biological diversity present during the initial millennia of human presence in the Americas. The specimens were compared to worldwide reference series through geometric morphometric analyses of 3D anatomical landmarks. Morphological data were analyzed through exploratory visual multivariate analyses and multivariate classification based on Mahalanobis distances. The results show very different patterns of morphological association for each Quintana Roo specimen, suggesting that the early populations of the region already shared a high degree of morphological diversity. This contrasts with previous studies of South American remains and opens the possibility that the initial populations of North America already had a high level of morphological diversity, which was reduced as populations dispersed into the southern continent. As such, the study of these rare remains illustrates that we are probably still underestimating the biological diversity of early Americans., Competing Interests: The authors have declared that no competing interests exist.

Objectives: This study analyzes craniofacial shape variation in the Hehuang region of Northwest China within a population genetic framework, and takes a diachronic approach to explore the relationship betwee cultural discontinuity and biological continuity/discontinuity in the Hehuang region during the middle to late Holocene., Materials and Methods: The sample comprises 76 adult skulls from five archaeological sites, ranging from 4,500 to 1,530 BP. 3D geometric morphometrics, multivariate statistics, quantitative evolutionary genetic and biodistance analyses were performed to study the diachronic variation in craniofacial morphology. Analyses were performed on two cranial modules: the face and the cranial vault, across three major diachronic groups representing the late Neolithic (LNA), the Bronze Age (BA), and the Han-Jin dynasty (HD)., Results: Average regional F ST for both cranial modules was low, indicating relatively greater variation within diachronic groups than among them. While the LNA and BA groups did not show any significant differences in facial and vault shape, significant craniofacial shape changes were detected between the BA and HD groups., Discussion: The consistent craniofacial morphology during the LNA and the BA, and the shift in morphology between the BA and the HD indicates that cultural discontinuity does not always coincide with biological discontinuity. The Hehuang population evolved in situ with few changes, despite cultural and dietary changes, until the HD when migrations from the Central Plains are associated with extra-local gene flow to the area., (© 2019 Wiley Periodicals, Inc.)

Anthropologists are increasingly turning to explicit model-bound evolutionary approaches for understanding the morphological diversification of humans and other primate lineages. Such evolutionary morphological analyses rely on three interconnected conceptual frameworks; multivariate morphometrics for quantifying similarity and differences among taxa, quantitative genetics for modeling the inheritance and evolution of morphology, and neutral theory for assessing the likelihood that taxon diversification is due to stochastic processes such as genetic drift. Importantly, neutral theory provides a framework for testing more parsimonious explanations for observed morphological differences before considering more complex adaptive scenarios. However, the consistency with which these concepts are applied varies considerably, which mirrors some of the theoretical obstacles faced during the "modern synthesis" of classical population genetics in the early 20th century. Here, each framework is reviewed and some potential stumbling blocks to the full conceptual integration of multivariate morphometrics, quantitative genetics, and neutral theory are considered., (© 2019 Wiley Periodicals, Inc.)

The purpose of this study was to compare fluctuating asymmetry (FA) levels across cranial modules of normal and pathological cranial specimens. It was examined whether pathological specimens have significantly higher FA scores than normal specimens in cranial regions affected by a developmental disorder. For this study, a modern Thai skeletal sample from Chulalongkorn University was analyzed. Ninety-two cranial landmarks were digitized on 66 adult and eight sub-adult normal specimens and on five pathological specimens including two adults with abnormal palates, two sub-adults with craniosynostosis, and one sub-adult with natal absence of nasal bones. In sub-adults, FA scores of specimens with developmental disorders were significantly higher than normal specimens in the entire cranium (p = 0.041) and vault (p = 0.025). However, comparisons excluding specimen with coronal craniosynostosis were not statistically significant. In adult specimens, comparisons of FA scores in each separate cranial module were also not statistically significant. These results suggest that elevated cranial FA may not be confined to the specific cranial region with the developmental disorder., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Objectives: Integration and modularity reflect the coordinated action of past evolutionary processes and, in turn, constrain or facilitate phenotypic evolvability. Here, we analyze magnitudes of integration in the macaque postcranium to test whether 20 a priori defined modules are (1) more tightly integrated than random sets of postcranial traits, and (2) are differentiated based on mode of definition, with developmental modules expected to be more integrated than functional or anatomical modules., Materials and Methods: The 3D morphometric data collected for eight limb and girdle bones for 60 macaques were collated into anatomical, developmental, and functional modules. A resampling technique was used to create random samples of integration values for each module for statistical comparison., Results: Our results found that not all a priori defined modules were more strongly integrated than random samples of postcranial traits and that specific types of modules did not present consistent patterns of integration. Rather, girdle and joint modules were consistently less integrated than limb modules, and forelimb elements were less integrated than hindlimbs., Discussion: The results suggest that morphometrically complex modules tend to be less integrated than simple limb bones, irrespective of the number of available traits. However, differences in integration of the fore- and hindlimb more likely reflects the multitude of locomotory, feeding, and social functions involved. It remains to be tested whether patterns of integration identified here are primate universals, and to what extent they vary depending on phylogenetic or functional factors., (© 2018 Wiley Periodicals, Inc.)

In the study of cultural evolution, observed among-group affinity patterns reflect the effects of processes such as mutation (e.g. innovation and copying error), between-group interaction (culture flow), drift and selection. As in biology, cultural affinity patterns are often spatially correlated, making it difficult to distinguish between the opposing geographically mediated forces of divergence and interaction, which cause groups to become more distinct or similar over time, respectively. Analogous difficulties are faced by evolutionary biologists examining the relationship between biological affinity and geography, particularly at lower taxonomic levels where the potential for gene flow between lineages is greatest. Tree models are generally used to assess the fit between affinity patterns and models of historical divergence. However, factors driving lineage divergence are often spatially mediated, resulting in tree models that are themselves geographically structured. Here, we showcase a simple method drawn from evolutionary ecology for assessing the relative impact of both geographically mediated processes simultaneously. We illustrate the method using global human craniometric diversity and material culture from the northern coast of New Guinea as example case studies. This method can be employed to quantify the relative importance of history (divergence) and geographically mediated between-group interaction (culture flow) in explaining observed cultural affinity patterns.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'., (© 2018 The Author(s).)

Objectives: Debate persists regarding the biological makeup of European Ottoman communities settled during the expansion of the Ottoman Empire during the 16th and 17th centuries, and the roles of conversion and migration in shaping demography and population history. The aim of this study was to perform an assessment of the biological affinities of three European Ottoman series based on craniometric data., Materials and Methods: Craniometric data collected from three Ottoman series from Hungary and Romania were compared to European and Anatolian comparative series, selected to represent biological affinity representative of historically recorded migration and conversion influences. Sex-separated samples were analyzed using D 2 -matrices, along with principal coordinates and PERMANOVA analyses to investigate biological affinities. Discriminant function analysis was employed to assign Ottoman individuals to two potential classes: European or Anatolian., Results: Affinity analyses show larger than expected biological differences between males and females within each of the Ottoman communities. Discriminant function analyses show that the majority of Ottoman individuals could be classified as either European or Anatolian with a high probability. Moreover, location within Europe proved influential, as the Ottomans from a location of more geopolitical importance (Budapest) diverged from more hinterland communities in terms of biological affinity patterns., Discussion: The results suggest that male and female Ottomans may possess distinct population histories, with males and females divergent from each other in terms of their biological affinities. The Ottoman communities appear diverse in terms of constituting a mix of peoples from different biological backgrounds. The greater distances between sexes from the same community, and the differences between communities, may be evidence that the processes of migration and conversion impacted individual people and groups diversely., (© 2017 Wiley Periodicals, Inc.)

Hominoid cranial evolution is characterized by substantial phenotypic diversity, yet the cause of this variability has rarely been explored. Quantitative genetic techniques for investigating evolutionary processes underlying morphological divergence are dependent on the availability of good ancestral models, a problem in hominoids where the fossil record is fragmentary and poorly understood. Here, we use a maximum likelihood approach based on a Brownian motion model of evolutionary change to estimate nested hypothetical ancestral forms from 15 extant hominoid taxa. These ancestors were then used to calculate rates of evolution along each branch of a phylogenetic tree using Lande's generalized genetic distance. Our results show that hominoid cranial evolution is characterized by strong stabilizing selection. Only two instances of directional selection were detected; the divergence of Homo from its last common ancestor with Pan, and the divergence of the lesser apes from their last common ancestor with the great apes. In these two cases, selection gradients reconstructed to identify the specific traits undergoing selection indicated that selection on basicranial flexion, cranial vault expansion, and facial retraction characterizes the divergence of Homo, whereas the divergence of the lesser apes was defined by selection on neurocranial size reduction., (© 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.)

Competing Interests: The author declares no conflict of interest.

The nature and timing of the peopling of the Americas is a subject of intense debate. In particular, it is unclear whether high levels of between-group craniometric diversity in South America result from multiple migrations or from local diversification processes. Previous attempts to explain this diversity have largely focused on testing alternative dispersal or gene flow models, reaching conflicting or inconclusive results. Here, a novel analytical framework is applied to three-dimensional geometric morphometric data to partition the effects of population divergence from geographically mediated gene flow to understand the ancestry of the early South Americans in the context of global human history. The results show that Paleoamericans share a last common ancestor with contemporary Native American groups outside, rather than inside, the Americas. Therefore, and in accordance with some recent genomic studies, craniometric data suggest that the New World was populated by multiple waves of dispersion from northeast Asia throughout the late Pleistocene and early Holocene.

Objectives: Estimation of the variance-covariance (V/CV) structure of fragmentary bioarchaeological populations requires the use of proxy extant V/CV parameters. However, it is currently unclear whether extant human populations exhibit equivalent V/CV structures., Materials and Methods: Random skewers (RS) and hierarchical analyses of common principal components (CPC) were applied to a modern human cranial dataset. Cranial V/CV similarity was assessed globally for samples of individual populations (jackknifed method) and for pairwise population sample contrasts. The results were examined in light of potential explanatory factors for covariance difference, such as geographic region, among-group distance, and sample size., Results: RS analyses showed that population samples exhibited highly correlated multivariate responses to selection, and that differences in RS results were primarily a consequence of differences in sample size. The CPC method yielded mixed results, depending upon the statistical criterion used to evaluate the hierarchy. The hypothesis-testing (step-up) approach was deemed problematic due to sensitivity to low statistical power and elevated Type I errors. In contrast, the model-fitting (lowest AIC) approach suggested that V/CV matrices were proportional and/or shared a large number of CPCs. Pairwise population sample CPC results were correlated with cranial distance, suggesting that population history explains some of the variability in V/CV structure among groups., Discussion: The results indicate that patterns of covariance in human craniometric samples are broadly similar but not identical. These findings have important implications for choosing extant covariance matrices to use as proxy V/CV parameters in evolutionary analyses of past populations., (© 2016 Wiley Periodicals, Inc.)

The transmission of genes and culture between human populations has major implications for understanding potential correlations between history, biological, and cultural variation. Understanding such dynamics in 19th century, post-contact Native Americans on the western Great Plains is especially challenging given passage of time, complexity of known dynamics, and difficulties of determining genetic patterns in historical populations for whom, even today, genetic data for their descendants are rare. Here, biometric data collected under the direction of Franz Boas from communities penecontemporaneous with the classic bison-hunting societies, were used as a proxy for genetic variation and analyzed together with cultural data. We show that both gene flow and "culture flow" among populations on the High Plains were mediated by geography, fitting a model of isolation-by-distance. Moreover, demographic and cultural exchange among these communities largely overrode the visible signal of the prior millennia of cultural and genetic histories of these populations.

The transition to agriculture was a key event in human history. The extent to which this transition is associated with biological changes in different world regions remains debated. Cultural and osteological records in Lower Nubia throughout the Holocene have been interpreted as a result of in situ differentiation or alternatively as migratory events and possible admixture with surrounding populations. Here we investigated the patterns of craniofacial and mandibular variation from Mesolithic hunting-gathering to late farming, a period spanning 11,000 years. We analyzed 102 adult specimens spanning five cultural horizons: Mesolithic, A-group, C-group, Pharaonic and Meroitic, by means of 3D geometric morphometric methods, in order to assess shape variation and diachronic patterns at the transition to farming and in subsequent periods. Our results highlight a strong morphometric distinction between Mesolithic hunter-gatherers and farmers as well as differences between transitional and intensive farmers in mandibular variation which is consistent with differential impact of selective pressures on different regions of the skull. This study corroborates a major biological change during the transition from hunting to farming, supporting the masticatory-functional hypothesis for the mandible and suggesting population continuity among farming populations throughout the Holocene based on the overall shape of the cranium.

Objectives: In recent years, several studies have shown that populations from cold, high-latitude regions tend to have relatively shorter limbs than populations from tropical regions, with most of the difference due to the relative length of the zeugopods (i.e., radius, ulna, tibia, fibula). This pattern has been explained either as the consequence of long-term climatic selection or of phenotypic plasticity, with temperature having a direct effect on bone growth during development. The aims of this study were to test whether this pattern of intra-limb proportions extended to the bones of the hands and feet, and to determine whether the pattern remained significant after taking into account the effects of neutral evolutionary processes related to population history., Materials and Methods: Measurements of the limb bones, including the first metatarsal and metacarpal, were collected for 393 individuals from 10 globally distributed human populations. The relationship between intra-limb indices and minimum temperature was tested using generalized least squares regression, correcting for spatial autocorrelation., Results: The results confirmed previous observations of a temperature-related gradient in intra-limb proportions, even accounting for population history. This pattern extends to the hands, with populations from cold regions displaying a relatively shorter and stockier first metacarpal; however, the first metatarsal appears to be wider but not shorter in cold-adapted populations., Discussion: The results suggest that climatic adaptation played a role in shaping variation in limb proportions between human populations. The different patterns shown by the hands and feet might be due to the presence of evolutionary constraints on the foot to maintain efficient bipedal locomotion., (© 2015 Wiley Periodicals, Inc.)

The reconstruction of phylogenetic relationships in the primate fossil record is dependent upon a thorough understanding of the phylogenetic utility of craniodental characters. Here, we test three previously proposed hypotheses for the propensity of primate craniomandibular data to exhibit homoplasy, using a study design based on the relative congruence between cranial distance matrices and a consensus genetic distance matrix ("genetic congruence") for papionin taxa: 1) matrices based on cranial regions subjected to less masticatory strain are more genetically congruent than high-strain cranial matrices; 2) matrices based on cranial regions developing earlier in ontogeny are more genetically congruent than matrices based on regions that develop later; and 3) matrices based on cranial regions with greater anatomical/functional complexity are more genetically congruent than matrices based on anatomically simpler regions. Morphological distance matrices based on the shape of 15 different cranial regions, delineated on the basis of previous catarrhine studies, were statistically compared to a matrix of known genetic distances in papionins. Since sexual dimorphism and allometry are known to characterize this clade, several analytical iterations were conducted: 1) mixed-sex, male-only, and female-only analyses and 2) with and without an allometric scaling adjustment. Across all datasets, the chondrocranium matrix was the most consistently correlated with genetic distances, which is also consistent with previous studies of cercopithecoid taxa; however, there was no support for the internal predictions of the three hypotheses tested. Allometric scaling corrections had the largest impact on the genetic congruence of facial shape matrices, a result consistent with previous studies that have described facial homoplasy in papionin taxa. These findings differ from patterns described for hominoid taxa, suggesting that no single predictive criterion can explain phylogenetic utility of cranial datasets across catarrhine primate taxa. Many of the differences in morphological-genetic matrix correlations could result from different levels of phenotypic integration and evolvability in cercopithecoids and hominoids, suggesting that further study of these phenomena in extant primates is warranted., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

While it has been suggested that malocclusion is linked with urbanisation, it remains unclear as to whether its high prevalence began 8,000 years earlier concomitant with the transition to agriculture. Here we investigate the extent to which patterns of affinity (i.e., among-population distances), based on mandibular form and dental dimensions, respectively, match across Epipalaeolithic, Mesolithic, and Neolithic samples from the Near East/Anatolia and Europe. Analyses were conducted using morphological distance matrices reflecting dental and mandibular form for the same 292 individuals across 21 archaeological populations. Thereafter, statistical analyses were undertaken on four sample aggregates defined on the basis of their subsistence strategy, geography, and chronology to test for potential differences in dental and mandibular form across and within groups. Results show a clear separation based on mandibular morphology between European hunter-gatherers, European farmers, and Near Eastern transitional farmers and semi-sedentary hunter-gatherers. In contrast, the dental dimensions show no such pattern and no clear association between the position of samples and their temporal or geographic attributes. Although later farming groups have, on average, smaller teeth and mandibles, shape analyses show that the mandibles of farmers are not simply size-reduced versions of earlier hunter-gatherer mandibles. Instead, it appears that mandibular form underwent a complex series of shape changes commensurate with the transition to agriculture that are not reflected in affinity patterns based on dental dimensions. In the case of hunter-gatherers there is a correlation between inter-individual mandibular and dental distances, suggesting an equilibrium between these two closely associated morphological units. However, in the case of semi-sedentary hunter-gatherers and farming groups, no such correlation was found, suggesting that the incongruity between dental and mandibular form began with the shift towards sedentism and agricultural subsistence practices in the core region of the Near East and Anatolia.

Inferring the evolutionary history of the hominins is necessarily reliant on comparative analyses of fossilized skeletal anatomy. However, the reliability of different primate skeletal regions for recovering phylogenetic relationships is currently poorly understood. Historically, postcranial variation has largely been conceived of as reflecting locomotory and postural adaptation. The shape of the os coxae is central to such discussions given the divergent morphology displayed by the bipedal hominin pelvis relative to other primate taxa. While previous cladistic studies have suggested that postcranial and cranial datasets do not differ in terms of their propensity for homoplasy, methodological issues such as the numbers of characters and their quantification make it difficult to evaluate these findings. Here, we circumvent these problems by constructing morphological distance matrices based on cranial, mandibular and os coxae three-dimensional shape. Statistical comparisons of these morphological distance matrices against a single genetic distance matrix for 11 catarrhine taxa show that cranial and os coxae shape reflect genetic relationships better than the mandible when humans are included, and that the cranium and os coxae do not differ statistically in terms of their genetic correlations. When humans were excluded from the analyses, all three anatomical regions were equally strongly correlated with genetic distance. Moreover, a second analysis focusing solely on os coxae variation of 16 taxa demonstrated that os coxae shape correctly recovers catarrhine taxonomic relationships at the sub-family level, even when humans are included. Taken together, our results suggest that there is no a priori reason to favor cranial shape data over os coxae morphology when inferring the genetic relationships of extant or extinct primate taxa. Morphological similarities between humans and other primates differ depending on the skeletal element, suggesting that combining skeletal elements into a single analysis may provide more accurate reconstructions of genetic relationships., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Differences in the breadth of the pelvis among modern human populations and among extinct hominin species have often been interpreted in the light of thermoregulatory adaptation, whereby a larger pelvic girdle would help preserve body temperature in cold environments while a narrower pelvis would help dissipate heat in tropical climates. There is, however, a theoretical problem in interpreting a pattern of variation as evidence of selection without first accounting for the effects of neutral evolutionary processes (i.e., mutation, genetic drift and migration). Here, we analyse 3D configurations of 27 landmarks on the os coxae of 1494 modern human individuals representing 30 male and 23 female populations from five continents and a range of climatic conditions. We test for the effects of climate on the size and shape of the pelvic bone, while explicitly accounting for population history (i.e., geographically-mediated gene flow and genetic drift). We find that neutral processes account for a substantial proportion of shape variance in the human os coxae in both sexes. Beyond the neutral pattern due to population history, temperature is a significant predictor of shape and size variation in the os coxae, at least in males. The effect of climate on the shape of the pelvic bone, however, is comparatively limited, explaining only a small percentage of shape variation in males and females. In accordance with previous hypotheses, the size of the os coxae tends to increase with decreasing temperature, although the significance of the association is reduced when population history is taken into account. In conclusion, the shape and size of the human os coxae reflect both neutral evolutionary processes and climatically-driven adaptive changes. Neutral processes have a substantial effect on pelvic variation, suggesting such factors will need to be taken into account in future studies of human and fossil hominin coxal variation., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Context: Reconstructing the evolutionary history of fossil human taxa is heavily reliant on the ability to extract phylogenetic information from patterns of morphological variability. However, attempts to reconstruct phylogenetic relationships from craniodental data in extant primates have yielded inconsistent and inconclusive results., Objective: To critically evaluate a recent body of research, conducted within an explicitly quantitative genetics framework, which investigates the extent to which human cranial variation reflects past population history. Possible ways in which to extrapolate these human-specific insights to higher taxonomic levels will also be assessed., Results: A consensus is emerging confirming a largely neutral model for the human cranium, although specific instances of climatic and dietary adaptation have also been uncovered. Also, specific regions of the cranium, delineated according to particular criteria, differ in their relative genetic congruence. However, the genetic congruence patterns identified in modern humans are not replicated in other extant primates, calling their generality into question., Conclusions: Developing a clearer understanding of the evolution of morphological diversity in extinct taxa requires a different inference approach that focuses on assessing the evolutionary forces that shape these patterns, rather than the identification of particular morphological regions that correlate with genetic relatedness across all primates.

The Last Glacial Maximum (LGM) represents the most significant climatic event since the emergence of anatomically modern humans (AMH). In Europe, the LGM may have played a role in changing morphological features as a result of adaptive and stochastic processes. We use craniometric data to examine morphological diversity in pre- and post-LGM specimens. Craniometric variation is assessed across four periods--pre-LGM, late glacial, Early Holocene and Middle Holocene--using a large, well-dated, data set. Our results show significant differences across the four periods, using a MANOVA on size-adjusted cranial measurements. A discriminant function analysis shows separation between pre-LGM and later groups. Analyses repeated on a subsample, controlled for time and location, yield similar results. The results are largely influenced by facial measurements and are most consistent with neutral demographic processes. These findings suggest that the LGM had a major impact on AMH populations in Europe prior to the Neolithic., Competing Interests: Competing financial interests: The authors declare no competing financial interests.

The study of cranial variation has a long, and somewhat difficult, history within anthropology. Much of this difficulty is rooted in the historical use of craniometric data to justify essentialist typological racial classification schemes. In the post-war era of the "New Physical Anthropology" (sensu Washburn, 1951), anthropologists began to analyse human variation in an explicitly populationist and evolutionary philosophical and analytical framework. However, even within recent decades, substantially different approaches have been employed; some advocate a focus on the analysis of individual traits or clines, while others are explicitly adaptationist, with a focus on natural selection as the preeminent force of phenotypic diversification. In recent years, a series of studies have analysed craniometric data in an explicitly quantitative genetic framework, which emphasises the importance of neutral forces such as migration, gene flow and genetic drift in creating global patterns of phenotypic diversity. This approach has revealed that global patterns of cranial variation can largely be explained on the basis of neutral theory. Therefore, human cranial data can be productively employed as a proxy for neutral genetic data in archaeological contexts. Moreover, there is a growing recognition that regions of the cranium differ in the extent to which they fit a neutral model of microevolutionary expectation, allowing for a more detailed assessment of patterns of adaptation and phenotypic plasticity within the human skull. Taking an historical perspective, the current state of knowledge regarding patterns of cranial adaptation in response to climatic and dietary effects is reviewed. Further insights will be gained by better incorporating the study of cranial and postcranial variation, as well as understanding the impact of neutral versus non-neutral evolution in creating among-species diversity patterns in primates more generally. However, this will most effectively be achieved when comparative anatomy studies are situated within an explicitly quantitative genetic evolutionary framework.

The Neolithic transition in Europe was a complex mosaic spatio-temporal process, involving both demic diffusion from the Near East and the cultural adoption of farming practices by indigenous hunter-gatherers. Previous analyses of Mesolithic hunter-gatherers and Early Neolithic farmers suggest that cranial shape variation preserves the population history signature of the Neolithic transition. However, the extent to which these same demographic processes are discernible in the postcranium is poorly understood. Here, for the first time, crania and postcranial elements from the same 11 prehistoric populations are analysed together in an internally consistent theoretical and methodological framework. Results show that while cranial shape reflects the population history differences between Mesolithic and Neolithic lineages, relative limb dimensions exhibit significant congruence with environmental variables such as latitude and temperature, even after controlling for geography and time. Also, overall limb size is found to be consistently larger in hunter-gatherers than farmers, suggesting a reduction in size related to factors other than thermoregulatory adaptation. Therefore, our results suggest that relative limb dimensions are not tracking the same demographic population history as the cranium, and point to the strong influence of climatic, dietary and behavioural factors in determining limb morphology, irrespective of underlying neutral demographic processes.

Comparative studies of catarrhine pelvic morphology in an evolutionary framework play an important role in paleoanthropology, especially since this is the context from which human bipedalism eventually arose. Given the abundance of potentially confounding evolutionary and mechanical factors influencing pelvic form, it is important to tease apart the effects of shape and size in the major component of the primate pelvis, the os coxae. However, os coxae form is difficult to assess via traditional morphometric methods. Here, we adopt a 3D geometric morphometric approach to landmark data. Our analyses included data from 30 extant catarrhine taxa. Data were transformed and registered using Procrustes analysis and analyzed via examination of principal components. Two analyses were performed: one excluding Homo sapiens, and a second including them. Results of the first analysis demonstrate that the total diversity of os coxae morphology is significantly greater in hominoids than it is in cercopithecoids. This appears to be driven by the greater effects of size diversity (i.e., allometric effects) in the case of the hominoids. This analysis also revealed a clear taxonomic/phylogenetic distinction between hominoids and cercopithecoids in terms of os coxae shape. The second analysis showed that Procrustes distances in shape space are significantly greater between extant Pan and Homo than they are between any two non-human catarrhine taxa. This analysis thus quantifies, on a comparative basis, the dramatic effect that the course of hominin evolution had upon the morphology of the human pelvis, within what is - even by catarrhine standards--a relatively short span of evolutionary time., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Recent applications of population genetic models to human craniodental traits have revealed a strong neutral component to patterns of global variation. However, little work has been undertaken to determine whether neutral processes might also be influencing the postcranium, perhaps due to substantial evidence for selection and plastic environmental responses in these regions. Recent work has provided evidence for neutral effects in the pelvis, but has been limited in regard to shape data (small numbers of linear measurements) and restricted only to males. Here, we use geometric morphometric methods to examine population variation in the human os coxae (pelvic bone) in both males and females. Neutrality is examined via apportionment of variance patterns and fit to an Out-of-Africa serial founder effect model, which is known to structure neutral genetic patterns. Moreover, we compare males and females directly, and the true versus false pelvis, in order to examine potential obstetrical effects. Our results indicate evidence for substantial neutral population history effects on pelvic shape variation. They also reveal evidence for the effect of obstetrical constraints, but these affect males and females to equivalent extents. Our results do not deny an important role for selection in regard to specific aspects of human pelvic variation, especially in terms of features associated with body size and proportions. However, our analyses demonstrate that at a global level, the shape of the os coxae reveals substantial evidence for neutral variation. Our analyses thus indicate that population variation in the human pelvis might be used to address important questions concerning population history, just as the human cranium has done.

The extent to which past climate change has dictated the pattern and timing of the out-of-Africa expansion by anatomically modern humans is currently unclear [Stewart JR, Stringer CB (2012) Science 335:1317-1321]. In particular, the incompleteness of the fossil record makes it difficult to quantify the effect of climate. Here, we take a different approach to this problem; rather than relying on the appearance of fossils or archaeological evidence to determine arrival times in different parts of the world, we use patterns of genetic variation in modern human populations to determine the plausibility of past demographic parameters. We develop a spatially explicit model of the expansion of anatomically modern humans and use climate reconstructions over the past 120 ky based on the Hadley Centre global climate model HadCM3 to quantify the possible effects of climate on human demography. The combinations of demographic parameters compatible with the current genetic makeup of worldwide populations indicate a clear effect of climate on past population densities. Our estimates of this effect, based on population genetics, capture the observed relationship between current climate and population density in modern hunter-gatherers worldwide, providing supporting evidence for the realism of our approach. Furthermore, although we did not use any archaeological and anthropological data to inform the model, the arrival times in different continents predicted by our model are also broadly consistent with the fossil and archaeological records. Our framework provides the most accurate spatiotemporal reconstruction of human demographic history available at present and will allow for a greater integration of genetic and archaeological evidence.

Previous analyses of extant catarrhine craniodental morphology have often failed to recover their molecular relationships, casting doubt on the accuracy of hominin phylogenies based on anatomical data. However, on the basis of genetic, morphometric and environmental affinity patterns, a growing body of literature has demonstrated that particular aspects of cranial morphology are remarkably reliable proxies for neutral modern human population history. Hence, it is important to test whether these intra-specific patterns can be extrapolated to a broader primate taxon level such that inference rules for understanding the morphological evolution of the extinct hominins may be devised. Here, we use a matrix of molecular distances between 15 hominoid taxa to test the genetic congruence of 14 craniomandibular regions, defined and morphometrically delineated on the basis of previous modern human analyses. This methodology allowed us to test directly whether the cranial regions found to be reliable indicators of population history were also more reliable proxies for hominoid genetic relationships. Cranial regions were defined on the basis of three criteria: developmental-functional units, individual bones, and regions differentially affected by masticatory stress. The results found that all regions tested were significantly and strongly correlated with the molecular matrix. However, the modern human predictions regarding the relative congruence of particular regions did not hold true, as the face was statistically the most reliable indicator of hominoid genetic distances, as opposed to the vault or basicranium. Moreover, when modern humans were removed from the analysis, all cranial regions improved in their genetic congruence, suggesting that it is the inclusion of morphologically-derived humans that has the largest effect on incongruence between morphological and molecular estimates of hominoid relationships. Therefore, it may be necessary to focus on smaller intra-generic taxonomic levels to more fully understand the effects of neutral and selective evolutionary processes in generating morphological diversity patterns., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Debates surrounding the nature of the Neolithic demographic transition in Europe have historically centered on two opposing models: a "demic" diffusion model whereby incoming farmers from the Near East and Anatolia effectively replaced or completely assimilated indigenous Mesolithic foraging communities, and an "indigenist" model resting on the assumption that ideas relating to agriculture and animal domestication diffused from the Near East but with little or no gene flow. The extreme versions of these dichotomous models were heavily contested primarily on the basis of archeological and modern genetic data. However, in recent years a growing acceptance has arisen of the likelihood that both processes were ongoing throughout the Neolithic transition and that a more complex, regional approach is required to fully understand the change from a foraging to a primarily agricultural mode of subsistence in Europe. Craniometric data were particularly useful for testing these more complex scenarios, as they can reliably be employed as a proxy for the genetic relationships among Mesolithic and Neolithic populations. In contrast, modern genetic data assume that modern European populations accurately reflect the genetic structure of Europe at the time of the Neolithic transition, while ancient DNA data are still not geographically or temporally detailed enough to test continent-wide processes. Here, with particular emphasis on the role of craniometric analyses, we review the current state of knowledge regarding the cultural and biological nature of the Neolithic transition in Europe.

Alleged differences between Palaeolithic assemblages from eastern Asia and the west have been the focus of controversial discussion for over half a century, most famously in terms of the so-called 'Movius Line'. Recent discussion has centered on issues of comparability between handaxes from eastern Asian and 'Acheulean' examples from western portions of the Old World. Here, we present a multivariate morphometric analysis in order to more fully document how Mid-Pleistocene (i.e. ∼803 Kyr) handaxes from Bose Basin, China compare to examples from the west, as well as with additional (Mode 1) cores from across the Old World. Results show that handaxes from both the western Old World and Bose are significantly different from the Mode 1 cores, suggesting a gross comparability with regard to functionally-related form. Results also demonstrate overlap between the ranges of shape variation in Acheulean handaxes and those from Bose, demonstrating that neither raw material nor cognitive factors were an absolute impediment to Bose hominins in making comparable handaxe forms to their hominin kin west of the Movius Line. However, the shapes of western handaxes are different from the Bose examples to a statistically significant degree. Moreover, the handaxe assemblages from the western Old World are all more similar to each other than any individual assemblage is to the Bose handaxes. Variation in handaxe form is also comparatively high for the Bose material, consistent with suggestions that they represent an emergent, convergent instance of handaxe technology authored by Pleistocene hominins with cognitive capacities directly comparable to those of 'Acheulean' hominins.

Variation in the masticatory behavior of hunter-gatherer and agricultural populations is hypothesized to be one of the major forces affecting the form of the human mandible. However, this has yet to be analyzed at a global level. Here, the relationship between global mandibular shape variation and subsistence economy is tested, while controlling for the potentially confounding effects of shared population history, geography, and climate. The results demonstrate that the mandible, in contrast to the cranium, significantly reflects subsistence strategy rather than neutral genetic patterns, with hunter-gatherers having consistently longer and narrower mandibles than agriculturalists. These results support notions that a decrease in masticatory stress among agriculturalists causes the mandible to grow and develop differently. This developmental argument also explains why there is often a mismatch between the size of the lower face and the dentition, which, in turn, leads to increased prevalence of dental crowding and malocclusions in modern postindustrial populations. Therefore, these results have important implications for our understanding of human masticatory adaptation.

The extent to which the transition to agriculture in Europe was the result of biological (demic) diffusion from the Near East or the adoption of farming practices by indigenous hunter-gatherers is subject to continuing debate. Thus far, archaeological study and the analysis of modern and ancient European DNA have yielded inconclusive results regarding these hypotheses. Here we test these ideas using an extensive craniometric dataset representing 30 hunter-gatherer and farming populations. Pairwise population craniometric distance was compared with temporally controlled geographical models representing evolutionary hypotheses of biological and cultural transmission. The results show that, following the physical dispersal of Near Eastern/Anatolian farmers into central Europe, two biological lineages were established with limited gene flow between them. Farming communities spread across Europe, while hunter-gatherer communities located in outlying geographical regions adopted some cultural elements from the farmers. Therefore, the transition to farming in Europe did not involve the complete replacement of indigenous hunter-gatherer populations despite significant gene flow from the Southwest Asia. This study suggests that a mosaic process of dispersal of farmers and their ideas was operating in outlying regions of Europe, thereby reconciling previously conflicting results obtained from genetic and archaeological studies.

This study tests the relative efficacy of human cranial modules, defined on the basis of developmental and functional criteria, for reconstructing neutral genetic population history. Specifically, two hypotheses were tested: 1) The "basicranial hypothesis" predicts that the endochondrally ossifying basicranium will be more reliable for reconstructing population history than intramembranously ossifying regions of the human cranium. This is based on the assumption that early ossification of the basicranium and its distinct functional constraints produce a cranial structure that is relatively immune to non-neutral evolutionary forces. 2) The "single function hypothesis" predicts that cranial regions associated with a single (sensory) function are less reliable indicators of neutral genetic history. Here the prediction is based on the logic that complex, multi-functional, integrated cranial regions are less likely toexhibit homoplasy and, therefore, provide a more accurate morphological proxy for genetic relationships. The congruence between craniometric affinity matrices and neutral genetic population matrices based on autosomal microsatellite and classical markers was assessed using a series of Mantel and Dow-Cheverud tests. The results did not support the predictions of the "basicranial hypothesis," as the endochondrally ossifying basicranium was not significantly more congruent with the genetic data than intramembraneously ossifying modules. Moreover, although the results provided some support for the "single function hypothesis," defining cranial modules on the basis of anatomical or functional complexity did not provide a consistent means of predicting their phylogenetic efficacy. These results have important implications for building an accurate inference model of cranial evolution in the human fossil record., (2011 Wiley-Liss, Inc.)

Osseous and dental nonmetric (discrete) traits have long been used to assess population variability and affinity in anthropological and archaeological contexts. However, the full extent to which nonmetric traits can reliably be used as a proxy for genetic data when assessing close or familial relationships is currently poorly understood. This study represents the unique opportunity to directly compare genetic and nonmetric data for the same individuals excavated from the Egyin Gol necropolis, Mongolia. These data were analyzed to consider the general efficacy of nonmetric traits for detecting familial groupings in the absence of available genetic data. The results showed that the Egyin Gol population is quite homogenous both metrically and genetically confirming a previous suggestion that the same people occupied the necropolis throughout the five centuries of its existence. Kinship analysis detected the presence of potential family burials in the necropolis. Moreover, individuals buried in one sector of the necropolis were differentiated from other sectors on the basis of nonmetric data. This separation is likely due to an outside Turkish influence in the paternal line, as indicated by the results of Y-chromosome analysis. Affinity matrices based on nonmetric and genetic data were correlated demonstrating the potential of nonmetric traits for detecting relationships in the absence of genetic data. However, the strengths of the correlations were relatively low, cautioning against the use of nonmetric traits when the resolution of the familial relationships is low., (© 2010 Wiley-Liss, Inc.)

Recent studies have demonstrated that the shape of the human temporal bone is particularly strongly correlated with neutral genetic expectation, when compared against other cranial regions, such as the vault, face, and basicranium. In turn, this has led to suggestions that the temporal bone is particularly reliable in analyses of primate phylogeny and human population history. While several reasons have been suggested to explain the temporal bone's strong fit with neutral expectation, the temporal bone has never systematically been compared against other individual cranial bones defined using the same biological criteria. Therefore, it is currently unknown whether the shapes of all cranial bones possess reliable information regarding neutral genetic evolution, or whether the temporal bone is unique in this respect. This study tests the hypothesis that the human temporal bone is more congruent with neutral expectation than six other individual cranial bones by correlating population affinity matrices generated using neutral genetic and 3D craniometric data. The results demonstrate that while the temporal bone shows the absolute strongest correlation with neutral genetic data compared with all other bones, it is not statistically differentiated from the sphenoid, frontal, and parietal bones in this regard. Potential reasons for the temporal bone's consistently strong fit with neutral expectation, such as its overall anatomical complexity and/or its contribution to the architecture of the basicranium, are examined. The results suggest that future phylogenetic and taxonomic studies would benefit from considering the shape of the entire cranium minus those regions that deviate most from neutrality.

Background: The spread of agriculture into Europe and the ancestry of the first European farmers have been subjects of debate and controversy among geneticists, archaeologists, linguists and anthropologists. Debates have centred on the extent to which the transition was associated with the active migration of people as opposed to the diffusion of cultural practices. Recent studies have shown that patterns of human cranial shape variation can be employed as a reliable proxy for the neutral genetic relationships of human populations., Methodology/principal Findings: Here, we employ measurements of Mesolithic (hunter-gatherers) and Neolithic (farmers) crania from Southwest Asia and Europe to test several alternative population dispersal and hunter-farmer gene-flow models. We base our alternative hypothetical models on a null evolutionary model of isolation-by-geographic and temporal distance. Partial Mantel tests were used to assess the congruence between craniometric distance and each of the geographic model matrices, while controlling for temporal distance. Our results demonstrate that the craniometric data fit a model of continuous dispersal of people (and their genes) from Southwest Asia to Europe significantly better than a null model of cultural diffusion., Conclusions/significance: Therefore, this study does not support the assertion that farming in Europe solely involved the adoption of technologies and ideas from Southwest Asia by indigenous Mesolithic hunter-gatherers. Moreover, the results highlight the utility of craniometric data for assessing patterns of past population dispersal and gene flow.