Paleoneurology of an "early" Neandertal: endocranial size, shape, and features of Saccopastore 1

The Saccopastore 1 cranium was found near Rome in 1929, and its most probable age is about 120 ka (OIS 5e). The Neandertal morphology of the specimen was recognized just after the discovery by the Italian anthropologist S. Sergi, and subsequently confirmed by several authors. The present paper provides a complete description and analysis of the endocranial shape and features of this specimen, considering anatomical traits, metrics, and landmark data. The main endocranial diameters and the vascular traces resemble the morphology displayed by Middle Pleistocene humans, although lacking some traits described in the European samples referred to as ante-Neandertals. Nevertheless, proportions and endocranial shape support a definite Neandertal morphology, mostly taking into account the lateral development of the frontal lobes and the shape of the parietal areas. Therefore, it may be hypothesized that the Neandertal neurocranial architecture was present since at least OIS 5, as already suggested on the basis of ectocranial morphology

Midsagittal Cranial Shape Variation in the Genus Homo by Geometric Morphometrics

Midsagittal profiles of crania referred to different taxa of the genus Homo have been analyzed by geometric morphometric techniques. Comparisons between single specimens using the thin-plate-spline function suggest a generalized reduction of the lower face, associated with antero-posterior development of the braincase occurring (possibly in parallel evolution) along distinct human lineages. Furthermore, Neandertals display a projection of the midface, and modern humans show a derived globularity of the vault associated with midsagittal parietal bulging. Principal Component Analysis demonstrates a bimodal pattern of variation, which describes an »archaic« pole (rather heterogeneous in terms of taxonomy) clearly distinguishable from the modern one. The first two principal components – that explain together 80% of the total variance in shape – involve respectively fronto-parietal expansion and midfacial prognathism. These results contribute to identify different structural patterns in human evolution, supporting discontinuity rather than continuity of cranial shape among different taxa of the genus Homo, especially when considering the differences between Neandertals and early modern humans

La motivación a cooperar en las organizaciones y su relación con la frontera informal identificadora de los grupos humanos

En la presente tesis teórica se muestran las características que otras disciplinas ajenas a la Economía, principalmente la Antropología física y la Psicología evolucionista, han determinado como identificadoras del contexto en el que la motivación a cooperar surgió como rasgo adaptativo en los seres humanos, denominado a lo largo del texto Entorno Relacional de Homo sapiens (ERHs). Sobre estas bases, se propone un nuevo planteamiento teórico, la Frontera informal de los grupos humanos en las organizaciones, la estructura organizativa implícita a la que la predisposición conductual humana a cooperar se ha adaptado, y que sus integrantes determinan y evalúan constantemente, de manera no consciente. Cuando, en una organización, la totalidad de su estructura organizativa coincida con los caracteres de una Frontera informal, se favorecerán la aparición y el mantenimiento de conductas cooperativas entre sus miembros. Comparando los caracteres de la Frontera informal con las estructuras formales que generalmente gobiernan las organizaciones, será posible identificar aquellos aspectos en los que difieren, y en consecuencia, proponer cambios que faciliten la generalización de una motivación a cooperar.Cooperation among people is an adaptive trait, and as such, its motivation is innate; therefore, cooperate is a behavioural predisposition in humans. Different authors highlight that establishing an organizational context in line with the motivation to cooperate will make feasible for the interest of workers to side with the interest of their colleagues and the organization itself, as a mean for improving its functioning. This thesis is a theoretical work which explains the main characteristics identified by scientific disciplines not related with Economics, mainly Physical Anthropology and Evolutionary Psychology, as determining for the context in which the motivation to cooperate emerged as an adaptive trait in human beings, referred to in the text Relational Environment of Homo sapiens (REHs). According to the bases outlined in REHs, a new theoretical approach is proposed, the Informal boundary of human groups in organizations, that is the implicit organizational structure to which the human behavioural predisposition to cooperate has adapted, and which whose members determine and evaluate constantly in an unconscious way. When, in an organization, all its organizational structure fits in with the features of an Informal boundary, the emergence and maintenance of cooperative conducts among its members will be favoured. Comparing the features of the Informal boundary with the formal structures that usually govern organizations, it will be possible to identify those aspects in which they differ and, consequently, to propose changes that facilitate the generalization of a motivation to cooperate

Midsagittal Cranial Shape Variation in the Genus Homo by Geometric Morphometrics

Midsagittal profiles of crania referred to different taxa of the genus Homo have been analyzed by geometric morphometric techniques. Comparisons between single specimens using the thin-plate-spline function suggest a generalized reduction of the lower face, associated with antero-posterior development of the braincase occurring (possibly in parallel evolution) along distinct human lineages. Furthermore, Neandertals display a projection of the midface, and modern humans show a derived globularity of the vault associated with midsagittal parietal bulging. Principal Component Analysis demonstrates a bimodal pattern of variation, which describes an »archaic« pole (rather heterogeneous in terms of taxonomy) clearly distinguishable from the modern one. The first two principal components – that explain together 80% of the total variance in shape – involve respectively fronto-parietal expansion and midfacial prognathism. These results contribute to identify different structural patterns in human evolution, supporting discontinuity rather than continuity of cranial shape among different taxa of the genus Homo, especially when considering the differences between Neandertals and early modern humans

An angio-tomographic approach to the study of the variation of the middle meningeal artery in humans

Introduction. The middle meningeal artery usually enters the endocranial cavity through the foramen spinosum, running within the dura mater and developing a vascular network on the frontal, parietal, and occipital surfaces of the brain. Little information is available on its morphogenesis and variation in human populations or within primates (Falk 1993). Its imprints on the endocranial walls can be recognised on fossil specimens, allowing inferences on the evolution of this vascular system. While extinct human species display a limited reticulation of this vessels, Homo sapiens shows a definite increase of its complexity (Bruner et al., 2005). Current hypotheses on the evolution of a complex meningeal vascularisation in our species include biomechanical protection and thermoregulation of the brain surface (Bruner et al., 2011). Taking into account the limited knowledge on the variation of this arterial network, this study is aimed at quantifying individual differences in the branching patterns, as well as at investigating the spatial relationships between middle meningeal arteries, cerebral arteries, and neurocranial bones. Methods. Angio-tomography and digital anatomy are used to reconstruct in vivo the meningeal vascular system in 37 individuals with age spanning from 20 to 85 years. Three-dimensional reconstructions of the cerebral and meningeal vascular systems have been computed by using Mimics 11.1 (Materialise Software). Variations in basic branching patterns have been described by standard anatomical approaches, as well as by using standard morphometrics. Complexity of the branching pattern has been quantified also by using fractal approaches (Zamir 1999). Results. Anatomical descriptions and metrics are reported for different age classes, sexes, and hemispheres, providing mean values and ranges of distribution accounting for the vascular patterns. Conclusions. Although the middle meningeal network shows a variable and complex geometry, its spatial organization can be quantified in terms of branching patterns and topological relationships with the neurocranial elements. This information allows to test evolutionary hypothesis by quantifying individual or between-groups differences. At the same time this information is helpful in biomedical and neurosurgical context, providing statistical values for the position and distribution of the vessels

Open data, Science and Society: launching Oasis, the flagship initiative of the Istituto Italiano di Antropologia

The Open Data philosophy has gained considerable momentum in recent years, both in society and the scientific community. The accessibility via web of open data from the public sector has remarkably increased in the last decade, although there are substantial differences among nations (http://datacatalogs.org/). The expectation of many citizens, organizations and pressure groups (the so called “open government” movement) is that the free release of data from public administrations may help increase government transparency and accountability

What do brain endocasts tell us? A comparative analysis of the accuracy of sulcal identification by experts and perspectives in palaeoanthropology

Palaeoneurology is a complex field as the object of study, the brain, does not fossilize. Studies rely therefore on the (brain) endocranial cast (often named endocast), the only available and reliable proxy for brain shape, size and details of surface. However, researchers debate whether or not specific marks found on endocasts correspond reliably to particular sulci and/or gyri of the brain that were imprinted in the braincase. The aim of this study is to measure the accuracy of sulcal identification through an experiment that reproduces the conditions that palaeoneurologists face when working with hominin endocasts. We asked 14 experts to manually identify well-known foldings in a proxy endocast that was obtained from an MRI of an actual in vivo Homo sapiens head. We observe clear differences in the results when comparing the non-corrected labels (the original labels proposed by each expert) with the corrected labels. This result illustrates that trying to reconstruct a sulcus following the very general known shape/position in the literature or from a mean specimen may induce a bias when looking at an endocast and trying to follow the marks observed there. We also observe that the identification of sulci appears to be better in the lower part of the endocast compared to the upper part. The results concerning specific anatomical traits have implications for highly debated topics in palaeoanthropology. Endocranial description of fossil specimens should in the future consider the variation in position and shape of sulci in addition to using models of mean brain shape. Moreover, it is clear from this study that researchers can perceive sulcal imprints with reasonably high accuracy, but their correct identification and labelling remains a challenge, particularly when dealing with extinct species for which we lack direct knowledge of the brain