Dental topography and diets of platyrrhine primates

More than half a century ago, Percy Butler touted the importance of analyzing teeth to understand their function in an evolutionary context. There have been many advances in the study of dental functional morphology since that time. Here we review the various approaches to characterizing and comparing occlusal form that have been developed, especially dental topographic analysis. We also report on a new study of dental topography of platyrrhine primates (n = 341 individuals representing 16 species) with known differences in both dietary preferences and other food items eaten. Results indicate frugivores, gummivores, folivores, and seed eaters each have a unique combination of slope, relief, angularity, sharpness, and occlusal orientation patch size and count values. Likewise, among frugivores, those that supplement their diets with hard objects, insects, leaves, and seeds, also each have a distinctive suite of topographic features. We conclude that both primary and secondary diet choices select for occlusal form, and that functional morphology more reflects the types of foods and mechanical challenges they pose rather than the frequencies in which they are eaten.Peer reviewe

Possibilities of CT Scanning as Analysis Method in Laser Additive Manufacturing

Nordic Laser Materials Processing Conference Volume: 78 Host publication title: 15th Nordic Laser Materials Processing Conference, Nolamp 15Laser additive manufacturing is an established and constantly developing technique. Structural assessment should be a key component to ensure directed evolution towards higher level of manufacturing. The macroscopic properties of metallic structures are determined by their internal microscopic features, which are difficult to assess using conventional surface measuring methodologies. X-ray microtomography (CT) is a promising technique for three-dimensional non-destructive probing of internal composition and build of various materials. Aim of this study is to define the possibilities of using CT scanning as quality control method in LAM fabricated parts. Since the parts fabricated with LAM are very often used in high quality and accuracy demanding applications in various industries such as medical and aerospace, it is important to be able to define the accuracy of the build parts. The tubular stainless steel test specimens were 3D modelled, manufactured with a modified research AM equipment and imaged after manufacturing with a high-power, high-resolution CT scanner. 3D properties, such as surface texture and the amount and distribution of internal pores, were also evaluated in this study. Surface roughness was higher on the interior wall of the tube, and deviation from the model was systematically directed towards the central axis. Pore distribution showed clear organization and divided into two populations; one following the polygon model seams along both rims, and the other being associated with the concentric and equidistant movement path of the laser. Assessment of samples can enhance the fabrication by guiding the improvement of both modelling and manufacturing process.Peer reviewe

Automated 3D phenotype analysis using data mining

Peer reviewe

Building Digital 3D Learning Environments To Support the Teaching in Geosciences

Non peer reviewe

Virtual Reality in Natural Sciences

Virtual and augmented reality is a hot topic in education and research. To reach educators in natural sciences, Teatime Research Ltd and Department of Geosciences and Geography from the University of Helsinki organized a workshop during the LUMAT Symposium 2017. The participants were shown the possibilities of the technologies and software available, one of these being the locally developed Teatime Vrifier, a universal viewer for three dimensional data. To integrate these new technologies into educational workflows and daily use, it requires actual testing and exposure on all levels.Peer reviewe

The case of the grass‐eating suids in the Plio‐Pleistocene Turkana Basin: 3D dental topography in relation to diet in extant and fossil pigs

Two separate subfamilies of Plio‐Pleistocene African pigs (suids) consecutively evolved hypsodont and horizodont molars with flat occlusal surfaces, commonly interpreted as an adaptive trait to a grazing diet, similar to that of the present warthogs (Phacochoerus spp.). To investigate this in detail, we studied the 3D‐dental topography of fossil specimens from the Turkana Basin, using geographic information systems‐based methods. To establish baselines for interpretation of the Turkana Basin suids, topography of third molars of extant suids with known diets were analyzed: grazing warthog (Phacochoerus africanus), herbivorous mixed‐feeder forest hog (Hylochoerus meinertzhageni), omnivorous generalist wild boar (Sus scrofa), omnivorous fruit and tuber eater bush pig (Potamochoerus spp.), and omnivorous fruit eater babirusa (Babyrousa spp.) In addition, we analyzed supposedly browsing Miocene suids, Listriodon spp. The same topographic measures were applied to Plio‐Pleistocene specimens from the Turkana Basin, Kenya: Notochoerus euilus, Notochoerus scotti, Kolpochoerus heseloni, and Metridiochoerus andrewsi. With some differences between techniques, 3D‐dental topography analysis of extant suid molars mostly predicts the dietary differences between the species correctly. The grazing P. africanus differs from both the omnivorous suids and the herbivorous mixed‐feeder H. meinertzhageni in all except one metrics. The omnivorous mostly tropical suids, Potamochoerus and Babyrousa, primarily differ from the generalist, S. scrofa, in the orientation patch count analysis, showing higher occlusal complexity in the latter. Although, there might be significant gaps between the morphological changes and the ecological changes, we conclude that based on comparison of dental topography with the present‐day suids, N. scotti and M. andrewsi were most likely highly specialized grazers, while N. euilus and K. heseloni retained more of their ancestral, omnivorous heritage, but consumed grasses more than the extant omnivorous suids

A New Tooth Wear–Based Dietary Analysis Method for Proboscidea (Mammalia)

<div><p>ABSTRACT</p><p>Dietary analyses of herbivorous mammals are important for paleoecological reconstruction. Several methods applicable to fossil teeth have been developed lately. The mesowear method based on wear-induced occlusal shape and relief of ungulate molars has proven to be a robust method for dietary analysis. In its original form it can only be used for selenodont, plagiolophodont, and ectolophodont ungulate molars, but the principle can be extended to other kinds of tooth morphology. We introduce a new method of dietary analysis for proboscideans similar to the mesowear method, based on angle measurements from worn dentin valleys reflecting the relief of enamel ridges. The enamel ridges should be heavily worn when the abrasiveness of diet increases, resulting in lower occlusal relief and larger angles. For testing this, we compared the mesowear angles with stable carbon isotope values from dental enamel from populations of extant and fossil species from localities from Kenya and India. This enables us to compare diet and tooth wear in proboscideans, because the stable carbon isotope ratios in tropical environments provide a reliable standard for assessing the relative amounts of C4 and C3 plants in diet, and most of the C4 plants are grasses, which should be reflected in the mesowear signal.</p><p>SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP</p></div