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OBJECTIVES: The statistical analysis of fossil remains is essential to understand the evolution of the genus Homo. Unfortunately, the human fossil record is straight away scarce and plagued with severe loss of information caused by taphonomic processes. The recently developed field of Virtual Anthropology helps to ameliorate this situation by using digital techniques to restore damaged and incomplete fossils. MATERIALS AND METHODS: We present the package Arothron, an R software suite meant to process and analyze digital models of skeletal elements. Arothron includes tools to digitally extract virtual cavities such as cranial endocasts, to statistically align disarticulated or broken bony elements, and to visualize local variations between surface meshes and landmark configurations. RESULTS: We describe the main functionalities of Arothron and illustrate their usage through reproducible case studies. We describe a tool for segmentation of skeletal cavities by showing its application on a malleus bone, a Neanderthal tooth, and a modern human cranium, reproducing their shape and calculating their volume. We illustrate how to digitally align a disarticulated model of a modern human cranium, and how to combine piecemeal shape information on individual specimens into one. In addition, we present useful visualization tools by comparing the morphological differences between the right hemisphere of the Neanderthal and the modern human brain. CONCLUSIONS: The Arothron R package is designed to study digital models of fossil specimens. By using Arothron, scientists can handle digital models with ease, investigate the inner morphology of 3D skeletal models, gain a full representation of the original shapes of damaged specimens, and compare shapes across specimens.

Table S1. Procrustes ANOVA test for the significance of the species, life stage effects and their interaction on shape differences; Table S2. Test for a common multivariate allometric trajectory. (PDF 17 kb)

 Supplementary methods and results. (DOCX 316 kb)

International audience; The locality of Pietraroia (Lower Albian, southern Apennines, Italy) has provided two fully articulated crocodylomorphs, exposed in ventral and in dorsal aspect, which are described here as representing a new species of a new genus, Pietraroiasuchus ormezzanoi gen. nov, sp. nov. The new taxon is found to be the sister taxon of Pachycheilosuchus trinquei from the Albian of the Glen Rose Formation, Texas. Pietraroiasuchus ormezzanoi resolves the phylogenetic position of the controversial P. trinquei, and is crucial in enabling an extensive understanding of the family Hylaeochampsidae. Phylogenetic analysis places Hylaeochampsa vectiana as a sister group of Iharkutosuchus makadii plus Pachycheilosuchus and Pietraroiasuchus. The phylogenetic result reveals the presence of an evolutionary mosaicism within non-crocodylian eusuchians. Mosaic features in Pietraroiasuchus are denoted by the combination of primitive character states, such as the position of the choana with its anterior margin formed by an inverted V-shaped palatine processeses, and the presumed presence of a tiny antorbital fossa, in conjunction with derived states involving the slight vertebral procoelia, the presence of tetraserial segmented dermal armour with an accessory lateral row, and isolated nuchal osteoderms. The disjoint occurrence between Pachycheilosuchus and Pietraroiasuchus species suggests that Pietraroia was a refuge island inhabited by endemic forms.

HYLAEOCHAMPSIDAE ANDREWS, 1913 Definition A node-based clade stemming from the most recent common ancestor of Hylaeochampsa vectiana Andrews, 1913, Iharkutosuchus makadii Ösi et al., 2007, Pachycheilosuchus trinquei Rogers, 2003, and Pietraroiasuchus ormezzanoi. Revised diagnosis of hylaeochampsidae: Small eusuchians with brevirostral skull and thickned cranial and postcranial bones. Premaxillary (unknown in Hylaeochampsa and in Pachycheilosuchus) and anterior maxillary alveolar series of subequal size, maxilla posteriorly extends in a process devoid of teeth, minimal sculpturing of maxillary surface, reduced number of maxillary teeth, prefrontal longer than lachrymal (differing in Pietraroiasuchus, whereby the prefrontal and lachrymal are the same size, and unknown in P. trinquei); extremely narrow suborbital fenestra (unambiguous synapomorphy for the clade); choana anteriorly set in pterygoid (unknown in P. trinquei), pterygoid flanges relatively short and not reaching laterally the level of the quadrate medial condyle (unknown in P. trinquei), extremely robust ectopterygoid with expanded jugal and maxilla sutures, protuberance in the ventral surface of the quadrate with prominent muscle scars (unambiguous synapomorphy for the clade); vertical ridge at the occipital surface (unambiguous synapomorphy for the clade, unknown in P. trinquei), reduced anteroposterior extension of the quadrate articular process that does not (but may almost) reach the level of the occipital condyle (unambiguous synapomorphy for the clade, unknown in P. trinquei), anterodorsal margin of surangular elevated and extended (unknown in Hylaeochampsa)., Published as part of Buscalioni, Angela D., Piras, Paolo, Vullo, Romain, Signore, Marco & Barbera, Carmela, 2011, Early eusuchia crocodylomorpha from the vertebrate-rich Plattenkalk of Pietraroia (Lower Albian, southern Apennines, Italy), pp. 644-645 in Zoological Journal of the Linnean Society 163 (5) on pages 644-645, DOI: 10.1111/j.1096-3642.2011.00718.x, http://zenodo.org/record/5441720, {"references":["Andrews CW. 1913. On the skull and part of the skeleton a crocodile from the Middle Purbeck of Swanage, with the description of a new species (Pholidosaurus laevis) and a note on the skull of Hylaeochampsa. Annals and Magazine of Natural History 8: 485 - 494.","Osi A, Clark J, Weishampel DB. 2007. First report on a new basal eusuchian crocodyliform with multicusped teeth from the Upper Cretaceous (Santonian) of Hungary. Neues Jarhbuch fur Geologie und Palaontologie-Abhandlungen 243: 169 - 177.","Rogers JVI. 2003. Pachycheilosuchus trinquei, a new procoelous crocodyliform from the Lower Cretaceous (Albian) Glen Rose Formation of Texas. Journal of Vertebrate Paleontology 23: 128 - 145."]}

Seventeen extant populations of Microtus (Terricola) savii have been investigated for correlations of first lower molar shape to climatic variables by means of geometric morphometrics, and controlling for phylogenetic inheritance. Comparative methods revealed that climatic variables and phylogeography provide a very similar contribution to variation in first lower molars morphology, whereas tooth size does not appear to be affected by climatic conditions. Climate-related changes have been recognized in the anteroconid portion of the tooth. This indicates that molar tooth variation is strongly influenced by climatic conditions, although in a complex way. Calabrian populations, often ascribed to Microtus (Terricola) brachycercus, form a distinct cluster, in agreement with the most recent genetic analyses.

Modern shape analysis allows the fine comparison of shape changes occurring between different objects. Very often the classic machineries of generalized Procrustes analysis and principal component analysis are used in order to contrast the shape change occurring among configurations represented by homologous landmarks. However, if size and shape data are structured in different groups thus constituting different morphological trajectories, a data centering is needed if one wants to compare solely the deformation representing the trajectories. To do that, inter-individual variation must be filtered out. This maneuver is rarely applied in studies using simulated or real data. A geometrical procedure named parallel transport, that can be based on various connection types, is necessary to perform such kind of data centering. Usually, the Levi Civita connection is used for interpolation of curves in a Riemannian space. It can also be used to transport a deformation. We demonstrate that this procedure does not preserve some important characters of the deformation, even in the affine case. We propose a novel procedure called ‘TPS Direct Transport’ which is able to perfectly transport deformation in the affine case and to better approximate non affine deformation in comparison to existing tools. We recommend to center shape data using the methods described here when the differences in deformation rather than in shape are under study.

Background Understanding the mechanisms promoting or constraining morphological diversification within clades is a central topic in evolutionary biology. Ecological transitions are of particular interest because of their influence upon the selective forces and factors involved in phenotypic evolution. Here we focused on the humerus and mandibles of talpid moles to test whether the transition to the subterranean lifestyle impacted morphological disparity and phenotypic traits covariation between these two structures. Results Our results indicate non-subterranean species occupy a significantly larger portion of the talpid moles morphospace. However, there is no difference between subterranean and non-subterranean moles in terms of the strength and direction of phenotypic integration. Conclusions Our study shows that the transition to a subterranean lifestyle significantly reduced morphological variability in talpid moles. However, this reduced disparity was not accompanied by changes in the pattern of traits covariation between the humerus and the mandible, suggesting the presence of strong phylogenetic conservatism within this pattern.

The analysis of full Left Atrium (LA) deformation and whole LA deformational trajectory in time has been poorly investigated and, to the best of our knowledge, seldom discussed in patients with Hypertrophic Cardiomyopathy. Therefore, we considered 22 patients with Hypertrophic Cardiomyopathy (HCM) and 46 healthy subjects, investigated them by three–dimensional Speckle Tracking Echocardiography, and studied the derived landmark clouds via Geometric Morphometrics with Parallel Transport. Trajectory shape and trajectory size were different in Controls versus HCM and their classification powers had high AUC (Area Under the Receiving Operator Characteristic Curve) and accuracy. The two trajectories were much different at the transition between LA conduit and booster pump functions. Full shape and deformation analyses with trajectory analysis enabled a straightforward perception of pathophysiological consequences of HCM condition on LA functioning. It might be worthwhile to apply these techniques to look for novel pathophysiological approaches that may better define atrio–ventricular interaction.

Fil: Raia, Pasquale. Università degli Studi di Napoli Federico II; Italia Fil: Passaro, Federico. Università degli Studi di Napoli Federico II; Italia Fil: Carotenuto, Francesco. Università degli Studi di Napoli Federico II; Italia Fil: Maiorino, Leonardo. Università degli Studi Roma Tre; Italia Fil: Piras, Paolo. Università degli Studi Roma Tre; Italia Fil: Teresi, Luciano. Università degli Studi Roma Tre; Italia Fil: Meiri, Shai. Tel Aviv University; Israel Fil: Itescu, Yuval. Tel Aviv University; Israel Fil: Novosolov, Maria. Tel Aviv University; Israel Fil: Baiano, Mattia A. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Baiano, Mattia A. Instituto Catalán de Paleontología Miquel Crusafont; España Fil: Baiano, Mattia A. Universidad Nacional de Río Negro; Argentina Fil: Martínez, Ricard. Universitat Autònoma de Barcelona; España Fil: Fortelius, Mikael. University Of Helsinski; Finlandia Luxuriant, bushy antlers, bizarre crests, and huge, twisting horns and tusks are conventionally understood as products of sexual selection. This view stems from both direct observation and from the empirical finding that the size of these structures grows faster than body size (i.e., ornament size shows positive allometry).We contend that the familiar evolutionary increase in the complexity of ornaments over time in many animal clades is decoupled from ornament size evolution. Increased body size comes with extended growth. Since growth scales to the quarter power of body size, we predicted that ornament complexity should scale according to the quarter power law as well, irrespective of the role of sexual selection in the evolution and function of the ornament. To test this hypothesis, we selected three clades (ammonites, deer, and ceratopsian dinosaurs) whose species bore ornaments that differ in terms of the importance of sexual selection to their evolution.We found that the exponent of the regression of ornament complexity to body size is the same for the three groups and is statistically indistinguishable from0.25.We suggest that the evolution of ornament complexity is a by-product of Cope’s rule. We argue that although sexual selection may control size in most ornaments, it does not influence their shape.

The assessment of left ventricular shape changes during cardiac revolution may be a new step in clinical cardiology to ease early diagnosis and treatment. To quantify these changes, only point registration was adopted and neither Generalized Procrustes Analysis nor Principal Component Analysis were applied as we did previously to study a group of healthy subjects. Here, we extend to patients affected by hypertrophic cardiomyopathy the original approach and preliminarily include genotype positive/phenotype negative individuals to explore the potential that incumbent pathology might also be detected. Using 3D Speckle Tracking Echocardiography, we recorded left ventricular shape of 48 healthy subjects, 24 patients affected by hypertrophic cardiomyopathy and 3 genotype positive/phenotype negative individuals. We then applied Generalized Procrustes Analysis and Principal Component Analysis and inter-individual differences were cleaned by Parallel Transport performed on the tangent space, along the horizontal geodesic, between the per-subject consensuses and the grand mean. Endocardial and epicardial layers were evaluated separately, different from many ecocardiographic applications. Under a common Principal Component Analysis, we then evaluated left ventricle morphological changes (at both layers) explained by first Principal Component scores. Trajectories’ shape and orientation were investigated and contrasted. Logistic regression and Receiver Operating Characteristic curves were used to compare these morphometric indicators with traditional 3D Speckle Tracking Echocardiography global parameters. Geometric morphometrics indicators performed better than 3D Speckle Tracking Echocardiography global parameters in recognizing pathology both in systole and diastole. Genotype positive/phenotype negative individuals clustered with patients affected by hypertrophic cardiomyopathy during diastole, suggesting that incumbent pathology may indeed be foreseen by these methods. Left ventricle deformation in patients affected by hypertrophic cardiomyopathy compared to healthy subjects may be assessed by modern shape analysis better than by traditional 3D Speckle Tracking Echocardiography global parameters. Hypertrophic cardiomyopathy pathophysiology was unveiled in a new manner whereby also diastolic phase abnormalities are evident which is more difficult to investigate by traditional ecocardiographic techniques.

A mechanics–based analysis of data from three-dimensional speckle tracking echocardiography can help to infer useful clinical data about the state of myocardium. Precisely, we recently conjectured that principal strain lines in the left ventricle change in presence of heart disease, and used data from healthy subjects and patients to support our conjecture. Here, we set the first steps of our analysis relative to the left atrium, describing our method of acquisition, and discussing the key mechanical characteristics delivered by the echocardiographic device for healthy subjects and patients affected by hypertrophic cardiomyopathy.