All species demonstrate intraspecific anatomical variation. While generalisations such as Bergman's and Allen's rules have attempted to explain the geographic structuring of variation with some success, recent work has demonstrated limited support for these in certain Old World monkeys. This study extends this research to the baboon: a species that is widely distributed across sub-Saharan Africa and exhibits clinal variation across an environmentally disparate range. This study uses trend surface analysis to map the pattern of skull variation in size and shape in order to visualise the main axes of morphological variation. Patterns of shape and sizecontrolled shape are compared to highlight morphological variation that is underpinned by allometry alone. Partial regression is used to dissociate the effects of environmental terms, such as rainfall, temperature and spatial position. The diminutive Kinda baboon is outlying in size, so analyses were carried out with and without this taxon. Skull size variation demonstrates an east-west pattern, with small animals at the two extremes and large animals in Central and Southern Africa. Shape variation demonstrates the same geographical pattern as skull size, with small-sized animals exhibiting classic paedomorphic morphology. However, an additional northsouth axis of variation emerges. After controlling for skull size, the diminutive Kinda baboon is no longer an outlier for size and shape. Also, the east-west component is no longer evident and discriminant function analysis shows an increased misclassification of adjacent taxa previously differentiated by size. This demonstrates the east-west component of shape variation is underpinned by skull size, while the north-south axis is not. The latter axis is explicable in phylogenetic terms: baboons arose in Southern Africa and colonised East and West Africa to the north, diverging in the process, aided by climate-mediated isolating mechanisms. Environmental terms appear poorly correlated with shape variation compared with geography. This might indicate that there is no simple environment-morphology association, but certainly demonstrates that phylogenetic history is an overbearing factor in baboon morphological variation.
Measures of a range of relevant selection attributes and personal qualities can predict intermediate and end of course achievements in academic, clinical and professional behaviour domains. In this study HYMS academic score, some UKCAT subtest scores and the total UKCAT score, and some non-cognitive tests completed at the outset of studies, together predicted outcomes most comprehensively. Tutor evaluation of students early in the course also identified the more and less successful students in the three domains of academic, clinical and professional performance. These results may be helpful in informing the future development of selection tools.
Aim We characterize and compare patterns of clinal size variation among diverse widespread sub-Saharan monkeys with the aim of identifying commonalities and differences in biogeographical variation. Thus, we accurately quantify nonlinear clines in representatives of the main lineages of widespread sub-Saharan terrestrial and arboreal monkeys, and provide a crude numerical estimate of the strength of similarities across taxonomic groups.Location Sub-Saharan Africa.Methods Variations of skull centroid size, as a proxy for body mass, were modelled over sub-Saharan Africa within two terrestrial monkey species (Papio hamadryas and Chlorocebus aethiops) and two arboreal monkey taxa (Procolobus (Piliocolobus) sp., and the superspecies Cercopithecus nictitans-Cercopithecus mitis) using inverse distance weighting, thin-plate splines and kriging. The model with the highest cross-validated accuracy was used to produce contour plots that visualized clines and predicted size at equally spaced localities across overlapping areas of distribution ranges. Correlations among these predictions were used as a similarity measure among clines.Results Irrespective of phylogenetic distances and ecological differences, all groups showed similarities in clinal size over central Africa: large animals mostly live in and around the tropical forest of the Congo basin; size declines rapidly towards the Horn of Africa and the coasts of Kenya and Tanzania. Size also tends to decrease in western Africa but clinal patterns in this region vary, with vervets (Chlorocebus aethiops) exceptionally showing a size increase.Main conclusions Similarities in patterns of size across diverse monkey groups were found. Nonetheless, complexity in clines and a degree of heterogeneity across groups were evident, which is unlikely to be compatible with the exclusive effect on size of a single main environmental factor. Primary productivity may be most significant in relation to the consistent observation of large sizes in and adjacent to the central African tropical forest belt. Complex clines, such as those of African monkeys, are difficult to compare visually and data collection from evenly sampled sets of localities, where all species of interest may be found, is often impractical or simply not feasible for primates and other protected animals. The development of improved quantitative methods for the description and comparison of clines in mammals and other organisms is required.
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