Toward Measurement of Management by Objectives (MBO) Systems: An Integrative Approach

Kurt K. Motamedi is Professor of Management at Pepperdine University. Anthony P. Raia is Professor of Management in the Graduate School of Management at UCLA

Locomotory Adaptations in 3D Humerus Geometry of Xenarthra: Testing for Convergence

Three-dimensional (3D) models of fossil bones are increasingly available, thus opening a novel frontier in the study of organismal size and shape evolution. We provide an example of how photogrammetry can be combined with Geometric Morphometrics (GMM) techniques to study patterns of morphological convergence in the mammalian group of Xenarthra. Xenarthrans are currently represented by armadillos, sloths, and anteaters. However, this clade shows an incredibly diverse array of species and ecomorphotypes in the fossil record, including gigantic ground sloths and glyptodonts. Since the humerus is a weight-bearing bone in quadrupedal mammals and its morphology correlates with locomotor behavior, it provides an ideal bone to gain insight into adaptations of fossil species. A 3D sample of humerii belonging to extant and fossil Xenarthra allowed us to identify a significant phylogenetic signal and a strong allometric component in the humerus shape. Although no rate shift in the evolution of the humerus shape was recorded for any clade, fossorial and arboreal species humerii did evolve at significantly slower and faster paces, respectively, than the rest of the Xenarthran species. Significant evidence for morphological convergence found among the fossorial species and between the two tree sloth genera explains these patterns. These results suggest that the highly specialized morphologies of digging taxa and tree sloths represent major deviations from the plesiomorphic Xenarthran body plan, evolved several times during the history of the group

Arothron: an R package for virtual anthropology to build endocast and to perform digital reconstruction

Arothron is an R package [1] containing brand new tools for geometric morphometric analysis. The package comes with examples pertaining to the field of virtual anthropology, yet it is addressed to the entire audience of geometric morphometricians. The functions embedded in the package allow aligning disarticulated parts belonging to a single specimen (i.e. broken skull fragments), to build internal cavities such as endocasts, and to reproduce and analyse the shapes of three-dimensional objects. Arothron functions import and export landmark coordinates and 3D paths into ’landmarkAscii’ and ’am’ format files. The Digital Tool for Alignment (DTA) is a landmark-based methodology which allows aligning two or more portions of a 3D mesh (i.e. a disarticulated model, DM) by using a reference sample or model (RM) for comparison. To run DTA, a set of anatomical landmarks is defined on two separated portions of the DM. Each point of the landmark sets is moved to the nearest vertex of the triangles. This way, each landmark is identified by a number corresponding to a row of the vertex matrix of the mesh and its position is tracked on the 3D models moved in the Cartesian coordinate system.The second step is the alignment via Generalized Procrustes Analysis (GPA) of each part of the DM on each RM of the comparative sample, where the same landmark configuration as with the DM has been previously defined. The items of the reference sample are previously scaled to the mean of the single scale factors calculated for each half of the DM, separately, and symmetrized via reflection and relabelling, thereby producing a perfectly symmetrical, bilateral, and scaled landmark configurations (to avoid alignment error as introduced by asymmetry). The last step consists in the quantification of the morphological (Euclidean) distances between each part of the DM and the corresponding landmark configurations on each item in the RM set. Computer-Aided Laser Scanner Emulator (CA-LSE) and Automatic Segmentation Tool for 3D objects (AST-3D) are two new tools designed for the reconstruction of virtual cavities and external shapes [2]. CA-LSE provides the reconstruction of the external portions of a 3D mesh by simulating the action of a laser scanner. AST-3D performs the digital reconstruction of anatomical cavities as endocasts. Both tools use the definition of points of views that can be placed externally to the object (CA-LSE) or inside the object (AST-3D). By applying these tools is possible in few minutes to build virtual cavities as endocast, maxillary sinuses and trabecular bone. In the Arothron R package, we supplied three examples of reconstructing: the dental pulp cavity within a deciduous Neanderthal tooth, the network of blood vessels within a human malleus bone, and an endocast of a human skull.The tools could be used in virtual anthropology application.The digital alignment tool is efficient in find ideal alignments of broken pieces. It could be applied as the first step in virtual reconstruction on human fossil specimens that often consist of a disarticulated fragments such as BOU-VP12/130 (Australopithecus garhi), AL-442 (Australopithecus afarensis), OH5 (Paranthropus boisei), ATD6-15 and ATD6-69 (Homo antecessor), Amud 1 (Homo neanderthalensis), Le Moustier 1 (Homo neanderthalensis). The easily and quickly use of the Arothron R package to build virtual cavities may provide a new means largely applicable in virtual Anthropology. References:[1] Profico A., Veneziano A., Melchionna M., Piras P. & Raia P., 2018. Arothron: Geometric Morphometrics Analyses. R package version 1.0.1, developer version available at https://github/Arothron DOI:10.5281/zenodo.1218712.[2] Profico A., Schlager S., Valoriani V., Buzi C., Melchionna M., Veneziano A., Raia P., MoggifiCecchi J. & Manzi G., 2018. Reproducing the internal and external anatomy of fossil bones: Two new automatic digital tools. American Journal of Physical Anthropology

Trapped in the morphospace: The relationship between morphological integration and functional performance

The evolution of complex morphological structures can be characterized by the interplay between different anatomical regions evolving under functional integration in response to shared selective pressures. Using the highly derived humeral morphology of talpid moles as a model, here we test whether functional performance is linked to increased levels of evolutionary integration between humerus subunits and, if so, what the strength is of the relationship. Combining two-dimensional geometric morphometrics, phylogenetic comparative methods, and functional landscape modeling, we demonstrate that the high biomechanical performance of subterranean moles’ humeri is coupled with elevated levels of integration, whereas taxa with low-performance values show intermediate or low integration. Theoretical morphs occurring in high-performance areas of the functional landscape are not occupied by any species, and show a marked drop in covariation levels, suggesting the existence of a strong relationship between integration and performance in the evolution of talpid moles’ humeri. We argue that the relative temporal invariance of the subterranean environment may have contributed to stabilize humeral morphology, trapping subterranean moles in a narrow region of the landscape and impeding any attempt to reposition on a new ascending slope

TAS2R38 is a novel modifer gene in patients with cystic fbrosis

The clinical manifestation of cystic fbrosis (CF) is heterogeneous also in patients with the same cystic fbrosis transmembrane regulator (CFTR) genotype and in afected sibling pairs. Other genes, inherited independently of CFTR, may modulate the clinical manifestation and complications of patients with CF, including the severity of chronic sinonasal disease and the occurrence of chronic Pseudomonas aeruginosa colonization. The T2R38 gene encodes a taste receptor and recently its functionality was related to the occurrence of sinonasal diseases and upper respiratory infections. We assessed the T2R38 genotype in 210 patients with CF and in 95 controls, relating the genotype to the severity of sinonasal disease and to the occurrence of P. aeruginosa pulmonary colonization. The frequency of the PAV allele i.e., the allele associated with the high functionality of the T2R38 protein, was signifcantly lower in i) CF patients with nasal polyposis requiring surgery, especially in patients who developed the complication before 14 years of age; and ii) in CF patients with chronic pulmonary colonization by P. aeruginosa, especially in patients who were colonized before 14 years of age, than in control subjects. These data suggest a role for T2R38 as a novel modifer gene of sinonasal disease severity and of pulmonary P. aeruginosa colonization in patients with CF

Morphometric maps of bilateral asymmetry in the human humerus: An implementation in the R package morphomap

In biological anthropology, parameters relating to cross-sectional geometry are calculated in paired long bones to evaluate the degree of lateralization of anatomy and, by inference, function. Here, we describe a novel approach, newly added to the morphomap R package, to assess the lateralization of the distribution of cortical bone along the entire diaphysis. The sample comprises paired long bones belonging to 51 individuals (10 females and 41 males) from The New Mexico Decedent Image Database with known biological profile, occupational and loading histories. Both males and females show a pattern of right lateralization. In addition, males are more lateralized than females, whereas there is not a significant association between lateralization with occupation and loading history. Body weight, height and long-bone length are the major factors driving the emergence of asymmetry in the humerus, while interestingly, the degree of lateralization decreases in the oldest individuals

Successful isolation of viable adipose-derived stem cells from human adipose tissue subject to long-term cryopreservation: positive implications for adult stem cell-based therapeutics in patients of advanced age.

We examined cell isolation, viability, and growth in adipose-derived stem cells harvested from whole adipose tissue subject to different cryopreservation lengths (2-1159 days) from patients of varying ages (26-62 years). Subcutaneous abdominal adipose tissue was excised during abdominoplasties and was cryopreserved. The viability and number of adipose-derived stem cells isolated were measured after initial isolation and after 9, 18, and 28 days of growth. Data were analyzed with respect to cryopreservation duration and patient age. Significantly more viable cells were initially isolated from tissue cryopreserved2 years, irrespective of patient age. However, this difference did not persist with continued growth and there were no significant differences in cell viability or growth at subsequent time points with respect to cryopreservation duration or patient age. Mesenchymal stem cell markers were maintained in all cohorts tested throughout the duration of the study. Consequently, longer cryopreservation negatively impacts initial live adipose-derived stem cell isolation; however, this effect is neutralized with continued cell growth. Patient age does not significantly impact stem cell isolation, viability, or growth. Cryopreservation of adipose tissue is an effective long-term banking method for isolation of adipose-derived stem cells in patients of varying ages

Decoupling Functional and Morphological Convergence, the Study Case of Fossorial Mammalia

Morphological similarity between biological structures in phylogenetically distant species is usually regarded as evidence of convergent evolution. Yet, phenotypic similarity is not always a sign of natural selection acting on a particular trait, therefore adaptation to similar conditions may fail to generate convergent lineages. Herein we tested whether convergent evolution occurred in the humerus of fossorial mammals, one of the most derived biological structures among mammals. Clades adapting to digging kinematics possess unusual, by mammalian standards, humeral shapes. The application of a new, computationally fast morphological test revealed a single significant instance of convergence pertaining to the Japanese fossorial moles (Mogera) and the North-American fossorial moles (Scalopini). Yet, the pattern only manifests when trade-off performance data (derived from finite element analysis) are added to shape data. This result indicates that fossorial mammals have found multiple solutions to the same adaptive challenge, independently moving around multiple adaptive peaks. This study suggests the importance of accounting for functional trade-off measures when studying morpho-functional convergence. We revealed that fossorial mammals, a classic example of convergent evolution, evolved multiple strategies to exploit the subterranean ecotope, characterized by different functional trade-offs rather than converging toward a single adaptive optimum

Quantitative genetics of body size evolution on islands: an individual-based simulation approach

According to the island rule, small-bodied vertebrates will tend to evolve larger body size on islands, whereas the opposite happens to large-bodied species. This controversial pattern has been studied at the macroecological and biogeographical scales, but new developments in quantitative evolutionary genetics now allow studying the island rule from a mechanistic perspective. Here, we develop a simulation approach based on an individual-based model to model body size change on islands as a progressive adaptation to a moving optimum, determined by density-dependent population dynamics. We applied the model to evaluate body size differentiation in the pigmy extinct hominin Homo floresiensis, showing that dwarfing may have occurred in only about 360 generations (95% CI ranging from 150 to 675 generations). This result agrees with reports suggesting rapid dwarfing of large mammals on islands, as well as with the recent discovery that small-sized hominins lived in Flores as early as 700 kyr ago. Our simulations illustrate the power of analysing ecological and evolutionary patterns from an explicit quantitative genetics perspective

A 450 million years long latitudinal gradient in age-dependent extinction.

Leigh Van Valen famously stated that under constant conditions extinction probability is independent of species age. To test this 'law of constant extinction', we developed a new method using deep learning to infer age-dependent extinction and analysed 450 myr of marine life across 21 invertebrate clades. We show that extinction rate significantly decreases with age in > 90% of the cases, indicating that most species died out soon after their appearance while those which survived experienced ever decreasing extinction risk. This age-dependent extinction pattern is stronger towards the Equator and holds true when the potential effects of mass extinctions and taxonomic inflation are accounted for. These results suggest that the effect of biological interactions on age-dependent extinction rate is more intense towards the tropics. We propose that the latitudinal diversity gradient and selection at the species level account for this exceptional, yet little recognised, macroevolutionary and macroecological pattern