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Modern humans have populated Europe for more than 45,000 years1,2. Our knowledge of the genetic relatedness and structure of ancient hunter-gatherers is however limited, owing to the scarceness and poor molecular preservation of human remains from that period3. Here we analyse 356 ancient hunter-gatherer genomes, including new genomic data for 116 individuals from 14 countries in western and central Eurasia, spanning between 35,000 and 5,000 years ago. We identify a genetic ancestry profile in individuals associated with Upper Palaeolithic Gravettian assemblages from western Europe that is distinct from contemporaneous groups related to this archaeological culture in central and southern Europe4, but resembles that of preceding individuals associated with the Aurignacian culture. This ancestry profile survived during the Last Glacial Maximum (25,000 to 19,000 years ago) in human populations from southwestern Europe associated with the Solutrean culture, and with the following Magdalenian culture that re-expanded northeastward after the Last Glacial Maximum. Conversely, we reveal a genetic turnover in southern Europe suggesting a local replacement of human groups around the time of the Last Glacial Maximum, accompanied by a north-to-south dispersal of populations associated with the Epigravettian culture. From at least 14,000 years ago, an ancestry related to this culture spread from the south across the rest of Europe, largely replacing the Magdalenian-associated gene pool. After a period of limited admixture that spanned the beginning of the Mesolithic, we find genetic interactions between western and eastern European hunter-gatherers, who were also characterized by marked differences in phenotypically relevant variants. Ancient DNA data generation Before the LGM LGM in southwestern and western Europe Post-LGM in the Italian peninsula Post-LGM in western and central Europe Post-14 ka to Neolithic Phenotypically relevant variants Discussion and conclusions Methods

The primate talus is known to have a shape that varies according to differences in locomotion and substrate use. While the human (Homo sapiens) talus is morphologically specialized for bipedal walking, relatively little is known how its morphology varies in relation to cultural and behavioral differences across time3. Here, we investigate differences in external and internal structure of 142 tali belonging to modern human populations with different levels of mobility (e.g., sedentary vs. nomadic), shoes (e.g., unshod/minimally shod vs. stiff footwear) and substrate use (e.g., asphalt vs. rough terrain). External talar morphology was investigated through 3D landmark-based geometric morphometric methods. Individuals were Procrustes superimposed (GPA) and then Procrustes coordinates were subject to Principal Component Analysis based on the group mean covariance. ANOVA Post Hoc test was carried out to identify group differences while Procrustes ANOVA was performed to assess effects of shape variation due to footwear, substrate and levels of mobility. Moreover, a subsample was selected for whole bone trabecular analysis for evaluating bone volume fraction (BV/TV), degree of anisotropy (DA) and elastic modulus (E). Our results show significant differences in both external and internal talar morphology between more sedentary groups (farmers and post-industrial individuals) and highly mobile hunter-gatherers. Morphological traits suggest that hunter-gatherers exhibit a more “flexible” talar shape providing broad range of joint motion while walking barefoot, or wearing minimalistic footwear, along uneven ground. Contrary, post-industrial people/farmers show a more “stable” profile reducing extensive foot motion by remaining constricted by the shoe. Differences in trabecular density and elastic modulus reflect a gracilization in sedentary people likely due to a decrease in daily physical activity, while talar robusticity in hunter-gatherers reflect highly mobility and distances travelled. This study points out that the modern human talus varies according to differences in mobility strategy.

Methods for age estimation in juvenile osteological samples are highly accurate compared to those of adults, but little is known about the variation of the foot bones during growth. This study explores the age-related morphological changes of the calcaneus, which is often well preserved even in the case of multiple or damaged burials, using Geometric Morphometric Methods. A sample of 33 modern human juvenile calcanei (known age/sex= 22; unknown sex/age= 11) was 3D scanned using an Artec3D Space Scanner. 5 age categories (0-15 years) were defined; unknown sex/age specimens were classified as ND. A template of 15 landmarks and 209 semi-landmarks was applied to the digital models. The (semi)landmark configurations were superimposed by Generalized Procrustes Analysis. A form space Principal Component Analysis (PCA) was computed using the known sample to explore variation during growth, while ND specimens were projected within it. The analysis shows that PC1 (ca. 93%) is highly correlated with size and accounts for ontogenetic allometry. Negative scores (youngest individuals) are characterized by a compact morphology while positive scores (oldest individuals) show both a greater definition of the sustentaculum talii and sinus tarsii and more pronounced edges for the talar and cuboid articular facets. The projected sample follows the trajectory of the known sample, which means that our ND specimens can be aged in the 5 categories after being projected. Our results suggest that age-related morphological changes of the calcaneus during growth may be used to estimate the general age of juvenile skeletal remains.

Age estimation is a fundamental aspect in juvenile osteological studies and, as such, there are many methods that rely on ontogenetic-related changes to bone morphology. The talus, being a small and compact bone, is generally well preserved in archaeological contexts, but little is known about its morphological trajectory during growth. To better nderstand this we apply a (semi)landmark-based approach to an ontogenetic sample of 26 modern human juvenile tali (known age/sex = 12; unknown age/sex = 14), grouped by 5 age categories ranging from 0 to 15 years. A template of 11 landmarks and 205 semilandmarks were applied to 26 microCT-based digital models of the juvenile tali. These were superimposed by Generalized Procrustes Analysis with the semilandmarks freely sliding against recursive updates of the Procrustes consensus. Finally, individuals of unknown age/sex were projected into the form-space determined from a Principal Component Analysis of the known sample. Our results show that most of the morphometric variation is explained by PC1 (⁓91%), which is highly correlated with size and accounts for ontogenetic allometry. Negative scores (i.e., youngest) are related to a small and globular morphology. The positive scores (i.e., oldest) account for an elongation of the talar body, which is mainly related to the development of the neck and growth of the lateral malleolar facet. Overall, our preliminary results suggest that age-related morphological variations of the talus may be used to determine the general age of juvenile skeletal remains, which could be valuable to many archaeological and forensic researchers.

This paper summarizes the current state of knowledge about the millennial scale climate variability characterizing Marine Isotope Stage 3 (MIS 3) in S-Europe and the Mediterranean area and its effects on terrestrial ecosystems. The sequence of Dansgaard-Oeschger events, as recorded by Greenland ice cores and recognizable in isotope profiles from speleothems and high-resolution palaeoecological records, led to dramatic variations in glacier extent and sea level configuration with major impacts on the physiography and vegetation patterns, both latitudinally and altitudinally. The recurrent succession of (open) woodlands, including temperate taxa, and grasslands with xerophytic elements, have been tentatively correlated to GIs in Greenland ice cores. Concerning colder phases, the Greenland Stadials (GSs) related to Heinrich events (HEs) appear to have a more pronounced effect than other GSs on woodland withdrawal and xerophytes expansion. Notably, GS 9-HE4 phase corresponds to the most severe reduction of tree cover in a number of Mediterranean records. On a long-term scale, a reduction/opening of forests throughout MIS 3 started from Greenland Interstadials (GIs) 14/13 (ca. 55–48 ka), which show a maximum in woodland density. At that time, natural environments were favourable for Anatomically Modern Humans (AMHs) to migrate from Africa into Europe as documented by industries associated with modern hominin remains in the Levant. Afterwards, a variety of early Upper Palaeolithic cultures emerged (e.g., Uluzzian and Proto-Aurignacian). In this chronostratigraphic framework, attention is paid to the Campanian Ignimbrite tephra marker, as a pivotal tool for deciphering and correlating several temporal-spatial issues crucial for understanding the interaction between AMHs and Neandertals at the time of the Middle to Upper Palaeolithic transition.

Introduction to the Special Issue "Peopling dynamics in the Mediterranean area between 45 and 39 ky ago: state of art and new data", Quaternary International, 551, 1-6 pp. in the framework of the European Research Council, ERC CoG no. 724046 SUCCESS (awarded to S. Benazzi; website: http://www.erc-success.eu).

The human talus, being located between the lower limb and foot, plays an essential role in distributing the weight of the body during locomotion. One of its most important functions during this process is in allowing for foot movements while efficiently dividing weight between its anterior and posterior portions, where it articulates with the navicular and calcaneus, respectively [1]. As such, the talus plays a pivotal role in the different stages of human locomotion, from crawling, to initial bipedal acquisition, to full striding bipedalism at age 8 [1]. Unfortunately, little is known about the morphological changes of the talus during the first years of life, when infants acquire upright posture and gait maturation. Using a (semi)landmark based approach we analyse an ontogenetic sample of modern human tali with the aim of exploring the morphological variation of the talus during growth. From this we assess if the variation may then be related to the acquisition and transition to full bipedal locomotion, which might ultimately provide insight into the evolution of hominin bipedalism. The sample consists of 21 juvenile tali aged between 1.5 years and 11 years: 12 individuals from the Collection of Bologna, Italy (sex and age at death known) [2]; five from the archaeological sample of Roccapelago (Italy) [3]; four from the archaeological sample of Norris Farms #36 (Illinois, USA). All specimens were microCT scanned with a resolution of 20-40 µm. Avizo 9.3® (Visualization Sciences Group, SAS) was used to evaluate the quality of and pre-process the reconstructed scan data (e.g. crop or resample). Segmentation of the image data was performed using the MIA-clustering method [4] and then processed in Medtool 4.2 (Dr. Pahr Ingenieurs.e.U) to obtain 3D meshes of each talus. A template of 11 landmarks, 61 curve semilandmarks and 144 surface semilandmarks was created in Viewbox (dHAL Software) and applied to the 21 tali. The (semi)landmark configuration was superimposed by Generalized Procrustes Analysis, and semilandmarks were allowed to slide against recursive updates of the Procrustes consensus [5]. Finally, a form space Principal Component Analysis was carried out to explore talar shape variation during growth. Data were processed in R 3.4.3 (The R Foundation for Statistical Computing, 2017). The first three PCs explain 92.9% of the total variation. Most of the morphometric variation is explained by PC1 (89.8%), i.e. ontogenetic allometry, where negative scores account for small, sub-parallelepiped talar morphology (the youngest individuals), while positive scores account for an elongation of the entire body of the talus, due to the development of the neck, and a clear growth of the lateral malleolar facet, while the posterior side of the trochlear facet is not well defined yet. The anterior calcaneal facet is well developed since the youngest phases (negative scores), while the posterior calcaneal facet becomes larger, less triangular, and more concave towards PC1 positive. PC2 (1.7%) and PC3 (1.4%) describe only subtle morphological differences. Negative values of PC2 account for a longer lateral ridge, that shortens along positive values, due to the growth of the talar head, development of the neck, trochlea, and lateral malleolar facet, with a more concave aspect of the lateral side. It is also possible to discern a narrowing of the sulcus tali and a clear medial rotation of the talar head. PC3 negative scores show a more compact shape, that becomes higher along positive values with the development of the posterior calcaneal facet and head. This study is part of an ongoing project focusing on ontogenetic changes. Here we present preliminary results showing how external talar morphology varies during the early stages of human bipedalism. Future analyses will combine external morphological analyses with an assessment of trabecular bone architecture, thus providing a more holistic vision of these changes during development. Acknowledgements This project is funded by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 724046 - SUCCESS); website: http://www.erc-success.eu/. We are grateful to Dr Mirko Traversari for his willingness on the use of the Roccapelago sample. References: [1] Hellier, C.A., & Jeffery, N. 2006. Morphological plasticity in the juvenile talus. Foot and Ankle surgery, 12(3), 139-147. [2] Belcastro, M.G., Bonfiglioli, B., Pedrosi, M.E., Zuppello, M., Tanganelli, V., & Mariotti, V. 2017. The history and composition of the identified human skeletal collection of the Certosa Cemetery (Bologna, Italy, 19th‐20th century). International Journal of Osteoarchaeology. DOI: 10.1002/oa.2605 [3] Figus, C., Traversari M., Scalise L. M., Oxilia G., Vazzana A., Buti L., Sorrentino R., Gruppioni G., Benazzi, S. 2017. The study of commingled non-adult human remains: Insights from the 16th-18th centuries community of Roccapelago (Italy). Journal of Archaeological Science: Reports, 14:382-391 [4] Dunmore C.J., Wollny G., Skinner M.M. (2018) MIA-Clustering: a novel method for segmentation of paleontological material. PeerJ 6:e4374 [5] Rohlf, F.J., Slice, D. 1990. Extensions of the Procrustes method for the optimal superimposition of landmarks. Syst. Biol. 39, 40-59.

International audience; In this work, we explored the isotopic composition of faunal (rodents, rhinoceros and bison) and human skeletal remains from the Middle Pleistocene layers of Isernia la Pineta (Molise, Italy). We particularly focused on high spatial resolution isotope analyses of tooth enamel by laser ablation MC-ICP-MS for strontium isotopes and by micro-drilling sampling for oxygen isotopes. Results from bone specimens were compared with the isotope variability of modern plants collected in the area surrounding the site, in a radius of about 30 km. While the human group seems local, macro-mammals show a higher degree of mobility.

Archaeological information and paleoanthropological analysis align both teeth to Neanderthal. These results point out that the Broion and Roccia San Sebastiano teeth represent, along with the deciduous tooth Cavallo D (from the final Mousterian deposit of Grotta del Cavallo) [5], the most recent Neanderthal remains in Italy currently known.

This case report examines the differential diagnosis of an unusually fused chest belonging to a perinatal human remain retrieved in the crypt of Roccapelago (Italy). This specimen, which dated back to the final 18th century, showed a severe synostosis of the costovertebral articulations and posterior arches. The specimen was examined macroscopically and radiologically for the purpose of identify differences in mineral density. It also underwent computed tomography scan in order to create a 3D digital model and virtually reposition in anatomical position. The radiological trophism, size, and osteological maturity of the specimen are compatible with a perinate. The chest structure shows a characteristic crab like morphology, with the costovertebral articulations and some posterior arches completely fused. Accordingly, a diagnosis of Jarcho-Levin Syndrome has been suggested. This case appears to be the first report, to the knowledge of the authors, of a probable Jarcho-Levin syndrome, which dated before Jarcho and Levin codified this pathology in the scientific literature.

We obtained high-resolution elemental maps (pixel size ranging between 10 and 20 ?m) of the dental crown. - The two Roman teeth showed clear Pb variation through the crown, highly correlated with enamel growth trajectories, likely linked to lead environmental exposure during the individual's lifetime. - Individual SCR313: Pb peak at ~410 days, visible in both dentine and enamel. - Individual SCR249: low pre-natal Pb levels, that increase post-natally; a Pb peak coincides with the neonatal line. - We identified several areas in both enamel and dentine affected by post-depositional processes.

During the Upper Palaeolithic animal teeth were consistently used by Anatomically Modern Humans as ornamental and symbolic objects used to facilitate individual and group-level interaction. Two key Northeastern Italian sites, "Grotta di Fumane" (VR) and "Grotta del Broion" (VI) show that Cervus elaphus teeth were often used for this purpose. While Grotta di Fumane yielded evidence of red deer incisors with groovings on the root, Grotta del Broion testifies to the use of deer canines and a completely different techonological approach based on preparatory scraping and perforation by rotation. An in-detail description of these processes thanks to stereomicroscope and 3D digital microscope allowed us to uncover a pattern of regional variabiliy in tooth choice and alteration practices that may be linked to the adaptive strategies of Aurignacian and Gravettian hunter-gatherers of Northern Italy as well as to the emergence of a symbolic behaviour which is deeply rooteed in human culture.

The dispersal of the genus Homo out of Africa approximately 1.8 million years ago (Ma) has been understood within the context of changes in diet, behavior, and bipedal locomotor efficiency. While various morphological characteristics of the knee and ankle joints are considered part of a suite of traits indicative of, and functionally related to, habitual bipedal walking, the timing and phylogenetic details of these morphological changes remain unclear. To evaluate the timing of knee and ankle joint evolution, we apply geometric morphometric methods to three-dimensional digital models of the proximal and distal tibiae of fossil hominins, Holocene Homo sapiens, and extant great apes. Two sets of landmarks and curve semilandmarks were defined on each specimen. Because some fossils were incomplete, digital reconstructions were carried out independently to estimate missing landmarks and semilandmarks. Group shape variation was evaluated through shape–and form-space principal component analysis and fossil specimens were projected to assess variation in the morphological space computed from the extant comparative sample. We show that a derived proximal tibia (knee) similar to that seen in living H. sapiens evolved with early Homo at ∼2 Ma. In contrast, derived characteristics in the distal tibia appear later, probably with the arrival of Homo erectus. These results suggest a dissociation of the morphologies of the proximal and distal tibia, perhaps indicative of divergent functional demands and, consequently, selective pressures at these joints. It appears that longer distance dispersals that delivered the Dmanisi hominins to Georgia by 1.8 Ma and H. erectus to east–southeast Asia by 1.6 Ma were facilitated by the evolution of a morphologically derived knee complex comparable to that of recent humans and an ankle that was morphologically primitive. This research sets the foundation for additional paleontological, developmental, and functional research to better understand the mechanisms underlying the evolution of bipedalism.

Fossil evidence points to an African origin of Homo sapiens from a group called either H. heidelbergensis or H. rhodesiensis. However, the exact place and time of emergence of H. sapiens remain obscure because the fossil record is scarce and the chronological age of many key specimens remains uncertain. In particular, it is unclear whether the present day ‘modern’ morphology rapidly emerged approximately 200 thousand years ago (ka) among earlier representatives of H. sapiens1 or evolved gradually over the last 400 thousand years2. Here we report newly discovered human fossils from Jebel Irhoud, Morocco, and interpret the affinities of the hominins from this site with other archaic and recent human groups. We identified a mosaic of features including facial, mandibular and dental morphology that aligns the Jebel Irhoud material with early or recent anatomically modern humans and more primitive neurocranial and endocranial morphology. In combination with an age of 315 ± 34 thousand years (as determined by thermoluminescence dating)3, this evidence makes Jebel Irhoud the oldest and richest African Middle Stone Age hominin site that documents early stages of the H. sapiens clade in which key features of modern morphology were established. Furthermore, it shows that the evolutionary processes behind the emergence of H. sapiens involved the whole African continent.

Over the last century, humans from industrialized societies have witnessed a radical increase in some dental diseases. A severe problem concerns the loss of dental materials (enamel and dentine) at the buccal cervical region of the tooth. This ‘‘modern-day’’ pathology, called non-carious cervical lesions (NCCLs), is ubiquitous and worldwide spread, but is very sporadic in modern humans from pre-industrialized societies. Scholars believe that several factors are involved, but the real dynamics behind this pathology are far from being understood. Here we use an engineering approach, finite element analysis (FEA), to suggest that the lack of dental wear, characteristic of industrialized societies, might be a major factor leading to NCCLs. Occlusal loads were applied to high resolution finite element models of lower second premolars (P2) to demonstrate that slightly worn P2s envisage high tensile stresses in the buccal cervical region, but when worn down artificially in the laboratory the pattern of stress distribution changes and the tensile stresses decrease, matching the results obtained in naturally worn P2s. In the modern industrialized world, individuals at advanced ages show very moderate dental wear when compared to past societies, and teeth are exposed to high tensile stresses at the buccal cervical region for decades longer. This is the most likely mechanism explaining enamel loss in the cervical region, and may favor the activity of other disruptive processes such as biocorrosion. Because of the lack of dental abrasion, our masticatory apparatus faces new challenges that can only be understood in an evolutionary perspective.

Fibular metric variations have revealed their potential in distinguishing between males and females; however the fibula remains scarcely analyzed in studies of sexual dimorphism. This work aims at investigating sexually dimorphic features in fibular proximal and distal epiphyses through geometric morphometrics methods. A total of 136 left fibulae, from two Italian and one South African identified skeletal collections were virtually acquired through CT and laser scanning and analyzed using geometric morphometric methods. Statistical analyses were performed on shape, form, and size variables. Results show that fibular epiphyses are smaller with narrower articular surfaces in females than in males in both extremities. Relevant sexual differences emerge in fibular form and size for the two Italian samples but not for the South African one, likely for its small sample size. Discriminant analysis on form principal components (PCs) offers accuracy above 80% when the samples are pooled, and reaches accuracy of 80–93% when the Italian samples are considered separately. However, our method on form PCs was not successful for the South African sample (50–53% accuracy), possibly due to the small sample size. These results show relevant morphological variation in relation to fibular form and size, with a degree of accuracy that indicates the utility of the present method for sexing human fibulae in both forensic and bioarchaeological contexts for Italian samples.

Across Europe, the genetics of the Chalcolithic/Bronze Age transition is increasingly characterized in terms of an influx of Steppe-related ancestry. The effect of this major shift on the genetic structure of populations in the Italian Peninsula remains underexplored. Here, genome-wide shotgun data for 22 individuals from commingled cave and single burials in Northeastern and Central Italy dated between 3200 and 1500 BCE provide the first genomic characterization of Bronze Age individuals (n = 8; 0.001-1.2× coverage) from the central Italian Peninsula, filling a gap in the literature between 1950 and 1500 BCE. Our study confirms a diversity of ancestry components during the Chalcolithic and the arrival of Steppe-related ancestry in the central Italian Peninsula as early as 1600 BCE, with this ancestry component increasing through time. We detect close patrilineal kinship in the burial patterns of Chalcolithic commingled cave burials and a shift away from this in the Bronze Age (2200-900 BCE) along with lowered runs of homozygosity, which may reflect larger changes in population structure. Finally, we find no evidence that the arrival of Steppe-related ancestry in Central Italy directly led to changes in frequency of 115 phenotypes present in the dataset, rather that the post-Roman Imperial period had a stronger influence, particularly on the frequency of variants associated with protection against Hansen's disease (leprosy). Our study provides a closer look at local dynamics of demography and phenotypic shifts as they occurred as part of a broader phenomenon of widespread admixture during the Chalcolithic/Bronze Age transition. ispartof: CURRENT BIOLOGY vol:31 issue:12 pages:2576-+ ispartof: location:England status: published

Objectives Palate morphology is constantly changing throughout an individual's lifespan, yet its asymmetry during growth is still little understood. In this research, we focus on the study of palate morphology by using 3D geometric morphometric approaches to observe changes at different stages of life, and to quantify the impact of directional and fluctuating asymmetry on different areas at different growth stages. Materials and Methods The sample consists of 183 individuals (1–72 years) from two identified human skeletal collections of 19th and early 20th Century Italian contexts. A 3D‐template of 41 (semi)landmarks was applied on digital palate models to observe morphological variation during growth. Results Asymmetrical components of the morphological structure appears multidirectional on the entire palate surface in individuals, Directional and fluctuating asymmetry of human palate.

Direct radiocarbon dating of human remains is crucial for the accurate interpretation of prehistory. Yet given the scarcity of prehistoric human remains, direct dating is often too destructive for important fossils. The reduction of sample size necessary for dating bone is therefore of great interest to archaeologists, but the confounding factors of molecular preservation and contamination present great challenges to the radiocarbon dating community.This dissertation explores the reduction of sample size for radiocarbon dating Palaeolithic bone at the pretreatment and 14C measurement stages. Methodological tests were carried out on a selection of archaeological bones spanning the breadth of the radiocarbon method at varying levels of preservation. Our standard pretreatment protocol for ~500 mg bone was refined for

Roccia San Sebastiano is a tectonic-karstic cave located at the foot of the southern slope of Mt. Massico, in the territory of Mondragone (Caserta) in Campania (southern Italy). Systematic excavation has been carried out since 2001, leading to the partial exploration of an important Pleistocene deposit, extraordinarily rich in lithic and faunal remains. The aim of this paper is to (1) present the stratigraphic sequence of Roccia San Sebastiano, and (2) technologically describe the lithic materials of squares F14 t18, t19, t20; E16 t16, t17, t18 recently recognised as Uluzzian. The stratigraphic sequence is more than 3 m thick and dates from the Middle to the Upper Palaeolithic. It contains different techno-complexes: Gravettian, Aurignacian, Uluzzian and Mousterian. In the Uluzzian lithic assemblage mostly local pebbles of chert were used in order to produce small-sized objects. The concept of debitage mainly deals with unidirectional debitage with absent or fairly accurate management of the convexities and angles; the striking platforms are usually natural or made by one stroke. It is attested the use of both direct freehand percussion and bipolar technique on anvil in the same reduction sequence. Amongst the retouched tools the presence of two lunates is of note. This study of the Roccia San Sebastiano Uluzzian lithic complexes is significant for understanding the dynamics of the transition from Middle to Upper Palaeolithic in the Tyrrhenian margin of southern Italy.

In this work, osteological and paleopathological analyses are combined with liquid-chromatography mass\ud spectrometry to study life and death of 30 non-adult individuals from an Early Medieval Italian funerary context\ud (Valdaro, 7th-8th cent. AD). We estimated individual sex by exploiting sexual differences in enamel-bounded\ud peptides. Enamel proteins were extracted through an acid etching of the whole tooth crowns for 4 samples\ud and through a partial digestion of small enamel chunks for the remaining 26 samples. Both protocols were\ud informative on the sex of the individuals through the identification of amelogenin isoforms (AMELX and\ud AMELY). In addition, low-mineralized tooth germs were analysed and they provided reliable information on the\ud infants’ sex. We observed the presence of 13 males and 17 females among the non-adults of Valdaro, not\ud significantly different from a random sample with an equal frequency of males and females. Cribra cranii and\ud endocranial lesion occurrence showed an association with sex, with higher frequencies in male individuals.

The adoption of bipedalism is a key benchmark in human evolution that has impacted talar morphology. Here, we investigate talar morphological variability in extinct and extant hominins using a 3D geometric morphometric approach. The evolutionary timing and appearance of modern human-like features and their contributions to bipedal locomotion were evaluated on the talus as a whole, each articular facet separately, and multiple combinations of facets. Distinctive suites of features are consistently present in all fossil hominins, despite the presence of substantial interspecific variation, suggesting a potential connection of these suites to bipedal gait. A modern human-like condition evolved in navicular and lateral malleolar facets early in the hominin lineage compared with other facets, which demonstrate more complex morphological variation within Homininae. Interestingly, navicular facet morphology of Australopithecus afarensis is derived in the direction of Homo, whereas more recent hominin species such as Australopithecus africanus and Australopithecus sediba retain more primitive states in this facet. Combining the navicular facet with the trochlea and the posterior calcaneal facet as a functional suite, however, distinguishes Australopithecus from Homo in that the medial longitudinal arch had not fully developed in the former. Our results suggest that a more everted foot and stiffer medial midtarsal region are adaptations that coincide with the emergence of bipedalism, whereas a high medial longitudinal arch emerges later in time, within Homo. This study provides novel insights into the emergence of talar morphological traits linked to bipedalism and its transition from a facultative to an obligate condition.