Late Pleistocene human genome suggests a local origin for the first farmers of central Anatolia

Anatolia was home to some of the earliest farming communities. It has been long debated whether a migration of farming groups introduced agriculture to central Anatolia. Here, we report the first genome-wide data from a 15,000-year-old Anatolian hunter-gatherer and from seven Anatolian and Levantine early farmers. We find high genetic continuity (~80–90%) between the hunter-gatherers and early farmers of Anatolia and detect two distinct incoming ancestries: an early Iranian/Caucasus related one and a later one linked to the ancient Levant. Finally, we observe a genetic link between southern Europe and the Near East predating 15,000 years ago. Our results suggest a limited role of human migration in the emergence of agriculture in central Anatolia

Evolutionary roots of the risk of hip fracture in humans

The transition to bipedal locomotion was a fundamental milestone in human evolution. Consequently, the human skeleton underwent substantial morphological adaptations. These adaptations are responsible for many of today’s common physical impairments, including hip fractures. This study aims to reveal the morphological changes in the proximal femur, which increase the risk of intracapsular hip fractures in present-day populations. Our sample includes chimpanzees, early hominins, early Homo Neanderthals, as well as prehistoric and recent humans. Using Geometric Morphometric methods, we demonstrate differences in the proximal femur shape between hominids and populations that practiced different lifestyles. We show that the proximal femur morphology is a risk factor for intracapsular hip fracture independent of osteoporosis. Changes in the proximal femur, such as the shortening of the femoral neck and an increased anterolateral expansion of the greater trochanter, are associated with an increased risk for intracapsular hip fractures. We conclude that intracapsular hip fractures are a trade-off for efficient bipedal walking in humans, and their risk is exacerbated by reduced physical activity

Changes in human calcaneal morphology throughout the Pleistocene-Holocene Levant

The calcaneal morphology changed considerably during human evolution to enable efficient bipedal locomotion. However, little information exists regarding its adaptation to changes in habitual activities following the transition to a sedentary lifestyle. We aimed to examine changes in calcaneal morphology during the Pleistocene-Holocene Levant in light of sexual dimorphism. We studied three archaic Homo sapiens calcanei dated to the Middle and Upper Paleolithic, 23 Natufian hunter-gatherers, 12 Pre-Pottery Neolithic early farmers, and 31 Chalcolithic farmers. The calcanei were scanned via a surface scanner and measured, and bone proportions were calculated. Measurements included the height, length, and width of various calcaneal elements. The sex of each individual was determined using methods based on calcaneal morphology. The validity of these methods was tested in those individuals who had the pelvis (92.3% agreement rate). Accordingly, the sample included 59.4% males and 40.6% females. Most calcaneal indices were sex-independent, except for the relative width, relative anterior length, and the cuboid index. Temporal trends between the Natufian and Chalcolithic periods were more pronounced among males than females. While in the proximal calcaneus, the temporal trend was similar between males and females, it differed in the distal part and articular facets. The calcanei of archaic H. sapiens exceeded the average of the Natufian hunter-gatherer for most variables, though the trend varied. To conclude, males and females were affected differently by the changing environment. The calcanei of archaic H. sapiens were better adapted for activity involving high mobility, independent of sex. During the transition to a sedentary way of life, different factors probably designed the male and female calcaneus. These could include factors related to the sexual division of labor, adaptation to lengthy standing, and changes in footwear

Frontal sinuses and human evolution

The frontal sinuses are cavities inside the frontal bone located at the junction between the face and the cranial vault and close to the brain. Despite a long history of study, understanding of their origin and variation through evolution is limited. This work compares most hominin species’ holotypes and other key individuals with extant hominids. It provides a unique and valuable perspective of the variation in sinuses position, shape, and dimensions based on a simple and reproducible methodology. We also observed a covariation between the size and shape of the sinuses and the underlying frontal lobes in hominin species from at least the appearance of Homo erectus. Our results additionally undermine hypotheses stating that hominin frontal sinuses were directly affected by biomechanical constraints resulting from either chewing or adaptation to climate. Last, we demonstrate their substantial potential for discussions of the evolutionary relationships between hominin species

Suggested case of Langerhans Cell Histiocytosis in a Cretaceous dinosaur

Susceptibility to diseases is common to humans and dinosaurs. Since much of the biological history of every living creature is shaped by its diseases, recognizing them in fossilized bone can furnish us with important information on dinosaurs' physiology and anatomy, as well as on their daily activities and surrounding environment. In the present study, we examined the vertebrae of two humans from skeletal collections with Langerhans Cell Histiocytosis (LCH), a benign osteolytic tumor-like disorder involving mainly the skeleton; they were diagnosed in life, along with two hadrosaur vertebrae with an apparent lesion. Macroscopic and microscopic analyses of the hadrosaur vertebrae were compared to human LCH and to other pathologies observed via an extensive pathological survey of a human skeletal collection, as well as a three-dimensional reconstruction of the lesion and its associated blood vessels from a µCT scan. The hadrosaur pathology findings were indistinguishable from those of humans with LCH, supporting that diagnosis. This report suggests that hadrosaurids had suffered from larger variety of pathologies than previously reported. Furthermore, it seems that LCH may be independent of phylogeny

Suggested case of Langerhans Cell Histiocytosis in a Cretaceous dinosaur

Susceptibility to diseases is common to humans and dinosaurs. Since much of the biological history of every living creature is shaped by its diseases, recognizing them in fossilized bone can furnish us with important information on dinosaurs' physiology and anatomy, as well as on their daily activities and surrounding environment. In the present study, we examined the vertebrae of two humans from skeletal collections with Langerhans Cell Histiocytosis (LCH), a benign osteolytic tumor-like disorder involving mainly the skeleton; they were diagnosed in life, along with two hadrosaur vertebrae with an apparent lesion. Macroscopic and microscopic analyses of the hadrosaur vertebrae were compared to human LCH and to other pathologies observed via an extensive pathological survey of a human skeletal collection, as well as a three-dimensional reconstruction of the lesion and its associated blood vessels from a µCT scan. The hadrosaur pathology findings were indistinguishable from those of humans with LCH, supporting that diagnosis. This report suggests that hadrosaurids had suffered from larger variety of pathologies than previously reported. Furthermore, it seems that LCH may be independent of phylogeny

Classical Taxonomy as the Foundation for Automating Fossil Identification: Using virtual paleontology and geometric morphometrics to identify Jurassic Nerineoidea gastropods

Accurate identification of fossils forms the foundation for many aspects of geological research, including biostratigraphy and paleoecology. Yet, many taxa are identified qualitatively based on their morphology, which requires extensive expertise in specific taxonomic groups. The often-subjective identification of specimens is difficult to verify and can cause misinterpretation and inaccuracies. Thus, finding new ways to objectively identify fossils will be of great value. A prime example of the ‘taxonomic impediment’ in the fossil record is exhibited in the Nerineoidea, a group of extinct gastropods that form a major component of Mesozoic shallow marine environments. Taxonomically diverse and numerically abundant assemblages of Nerineoidea are found across a wide range of paleo-latitudes, and used for biostratigraphy and paleoecology. The group is distinctly recognized by the presence of internal spiral folds that developed inside the internal cavity of the shell during ontogeny. The number and position of folds is constant within a species, and form the basis of their classification. Their paleoecological and biostratigraphical importance is represented by vast scientific literature and abundant fossil collections worldwide. However, identification and uniform classification of this group is lacking due to two major factors: inconsistent systematic position and subdivision, and the classification procedure is largely based on polished cross-sections of specimens that reveal the important internal structure and destroy whole specimens, thus preventing any further verification. Therefore, identification of specimens is largely based on expert judgment and difficult to replicate. Micro-computed tomography (micro-CT) is revolutionizing species identification by modeling the internal anatomy of fossils in 3D, and allowing the study of structures that would previously have been impossible to visualize. We present the first automated taxonomic identification method of Nerineoidea fossils, by combining modern non-destructive imaging techniques with classic identification methods. Fifty-eight Jurassic Nerineoidea specimens were examined from Europe, Arabia, and Africa. Images of polished cross-sections of specimens were compiled from online databases, literature, and fossil collections. Three successive longitudinal whorl cross-sections showing the internal folds were analyzed for each specimen. The shape of each whorl was captured using thirty evenly spaced semi-landmarks. In addition, twenty eight specimens from the Geological Survey of Israel and the Natural History Museum (UK) were scanned using micro-CT. Optimal longitudinal slices were selected from the 3D reconstructions for each specimen using Amira (v. 6.3), and their whorl outlines were captured as described above. Canonical variate analysis shows that whorl outlines significantly differentiate between Nerineoidea, independent of the data source or the location of the whorl in the spire. The Jackknife estimate of future identification is high (73.25%), and suggests that the method can be applied to accurately assign the taxonomic family of future specimens reliably and effectively. Moreover, the high variation in whorl outlines between genera can be used to identify specimens to the species level with a high level of certainty. We demonstrate that shape analysis of the whorl outlines is an objective and quantitative method for identifying different taxa of Nerineoidea. The advantages of the method include its application to mass accumulation of specimens, as well as to two-dimensional images from various sources. This will enable future quantitative study of polished cross-sections of specimens from museum collections, scientific publications and online databases. The quantitative and objective taxonomic identification of Nerineoidea fossils could revolutionize their classification and improve the paleoecological reconstruction of Mesozoic carbonate platforms. This will enhance interpretations of faunal biogeographic response to changing environmental conditions along shelf ecosystems

Three-Dimensional Surface Texture Analysis of Fluoride’s Effect on Enamel Erosion

Enamel erosion has become a common clinical finding that often impairs dental esthetics and function. In the current study, we aimed to implement the three-dimensional surface texture analysis (3DST) method to explore the protective effect of fluoride on surface texture prior to erosive conditions. For each of the 50 teeth used in this study, the polished buccal enamel surface was divided into three separate areas: the first area was untouched polished enamel, the two other surfaces were immersed in 0.3% citric acid for 30 s. One was treated with high-concentration (19,000 ppm) sodium fluoride (NaF) solution prior to acid attack, and the other had no treatment prior to acid exposure. Enamel surface texture and step height measurements were obtained using a high-resolution disk scanning confocal microscope, and SEM images were also acquired. Surfaces treated with fluoride showed fewer variations in 3-D surface texture parameters than the eroded surface compared to the control group (p = 0.001). This was in accordance with the SEM descriptive images. The findings indicate that pre-fluoridated enamel areas were less affected by the acid and showed similar features to the untouched enamel. Moreover, a protective effect of the fluoride treatment against irreversible enamel damage was noted as the surface loss (step-height) was significantly reduced (p = 0.03). The study showed that 3DST analysis is a valuable methodology for detecting and quantifying subtle differences between the surfaces. When exploring the combination of all surface texture parameters, it was revealed that the pre-fluoridated eroded enamel surfaces showed considerable similarity to the untouched enamel