Morphology of the inner structures of the facial skeleton in Homo neanderthalensis and the case-study of the Neanderthal from Altamura (Bari, Italy)

The PhD project has the aim to provide an accurate anatomical characterization of the facial regions (with a focus on the para-nasal areas) in the fossil human species Homo neanderthalensis, whose peculiar facial morphology is the topic of unresolved hypothesis on adaptation to climate and/or phylogenetic factors. Both can be at the origin of the variability of Neanderthals and can be taken into consideration, more in general, for the human populations from the Middle and Upper Pleistocene of Europe, thus from around 800 to 11 thousand years ago (ka). In this timespan, it can be seen a differential development of a set of cranial features which was resumed by J.J. Hublin and colleagues with the ‘accretion model’. In this scenario, a Neanderthal specimen from Italy, known as the ‘Altamura Man’ and discovered in 1993 in the Lamalunga karstic system in Apulia (southern Italy), represents a crucial subject of study, because its unique state of preservation and its antiquity, comprised between 172 and 130 ka. The nearly complete skeleton is still preserved in situ because of several factors, among which its exceptional completeness and thus has been the subject of a study of virtual paleoanthropology aimed at the reconstruction and observation of facial structures often damaged or completely absent in the fossil record

Visual analytics methods for shape analysis of biomedical images exemplified on rodent skull morphology

In morphometrics and its application fields like medicine and biology experts are interested in causal relations of variation in organismic shape to phylogenetic, ecological, geographical, epidemiological or disease factors - or put more succinctly by Fred L. Bookstein, morphometrics is "the study of covariances of biological form". In order to reveal causes for shape variability, targeted statistical analysis correlating shape features against external and internal factors is necessary but due to the complexity of the problem often not feasible in an automated way. Therefore, a visual analytics approach is proposed in this thesis that couples interactive visualizations with automated statistical analyses in order to stimulate generation and qualitative assessment of hypotheses on relevant shape features and their potentially affecting factors. To this end long established morphometric techniques are combined with recent shape modeling approaches from geometry processing and medical imaging, leading to novel visual analytics methods for shape analysis. When used in concert these methods facilitate targeted analysis of characteristic shape differences between groups, co-variation between different structures on the same anatomy and correlation of shape to extrinsic attributes. Here a special focus is put on accurate modeling and interactive rendering of image deformations at high spatial resolution, because that allows for faithful representation and communication of diminutive shape features, large shape differences and volumetric structures. The utility of the presented methods is demonstrated in case studies conducted together with a collaborating morphometrics expert. As exemplary model structure serves the rodent skull and its mandible that are assessed via computed tomography scans

Cranial form evolution and functional adaptations to diet among papionins : a comparative study combining quantitative genetics, geometric morphometrics, and finite element analysis

This thesis aims to study the evolution of cranial form and its biomechanical adaptation to the function of feeding in papionins, a group of primates with well-established phylogeny, large variations in cranial form, and well known ecologies and diets. The thesis firstly tests the hypothesis of evolutionary divergence of papionin cranial forms by random genetic drift with a quantitative genetic model (previously tested for acceptable type I error rates); if rejected, different cranial forms should reflect adaptations to the particular biomechanical demands of different diets. To study those adaptations, hypotheses about the cranial biomechanical performance under biting loads are then formulated in terms of the diet of each papionin species and tested using 3D finite element models and geometric morphometrics. Large scale deformations and cranial form are assessed using landmarks distributed over the cranium, and local strain distributions are assessed visually. Lastly, the association between cranial form, biomechanical parameters and diet among papionin species is tested using partial least squares. Results show that papionin cranial forms did not diverge by random genetic drift alone and thus adaptation must have occurred. When testing for biomechanical adaptation to biting, there are differences in cranial deformations between durophagous and graminivorous species, each with particular adaptations in the cranium that are thus apparent in cranial strains and deformations. Another striking result is that male and female crania of a single species (eating the same foods) deform similarly, albeit having different forms. The cranium of the phylogenetic outgroup Macaca deforms differently from all other papionins, but generally cranial deformations do not follow the phylogenetic relationship among papionins. Finally, a statistically significant association is found between cranial form and cranial deformations, and between diet and cranial form. Bite force and deformations show a less clear association with diet