This study developed a robust technique for the assessment of morphometric differences among overwintering northern fish populations. Arctic charr were sampled soon before the freeze-up and just after ice break-up at two subarctic Quebec lakes. A homogenous sample of 397 fish was used. Regression analyses of the length-weight relationships and their derived condition indices were insufficient, due to their inherent limitations, to recognize the differences between sampling groups. A series of multivariate analyses (canonical, stepwise and discriminant analysis), based on eleven morphometric characters of the fish, provided a better assessment. The analysis recognized the distinctions between sampling groups, correctly classified 70-100% of the fish into their appropriate groupings, and indicated that body height measured at the anal opening was the most discriminatory variable. Landmark variables related to shape differences were effective in discriminating fish according to their lake of origin, whereas length and weight variables, which closely reflected the size differences, were better at distinguishing seasonal changes. The study provides a simple, efficient assessment method based on phenotypic variations to explain different survival strategies, and the associated life history traits, adopted by fish.

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A dissertation submitted in fulfilment of the requirements for the Degree of Master of Science in Archaeology of the University of Witwatersrand in 2017. / Over the past decade a new method of statistical shape analysis, geometric morphometrics, has been applied to the study of artefact shapes. Later Stone Age (LSA) tanged stone arrowheads, hypothesized to act as stylistic markers among prehistoric southern African hunter-gatherer groups, have been analysed with geometric morphometrics and reveal spatially coherent variations in their shape. After being tested against several variables that may have had an effect on arrowhead shape, these stylistic spatial variations could very well indicate large scale linguistic or other kinds of boundaries between different elements of prehistoric San populations. Understanding them can shed light on the social and economic organization of southern African hunter-gatherers during the later Holocene. / LG2017

This is a study of the factors that affect face shapes, and the techniques that can be used to measure variations in two dimensional representations of faces. The materials included thirty photographs of people in natural poses and thirty portraits that were based on the pose photographs. Visual assessors were asked to score the photographs and portraits in terms of pose (cant, turn and pitch) and also to compare the portraits to the photographs and score them in terms of likeness in the depiction of the face and its component features. Anthropometric indices were derived and used to score the images for the pose variables as well as for aspects of individual variation in external face shape and the spatial arrangement of the features. Geometric morphometric analysis was also used to determine the shape variation occurring in the photographs, the variation within the portraits, and to specifically discern where the portraits differ from the photographs in the depiction of head pose and individual differences in facial morphology. For the analysis of pose it was found that visual assessors were best at discerning the extent of head turning and poorest at discerning head pitch. These tendencies occurred in the visual assessments of both the photographs and the portrait drawings. For the analysis of the individual variation in face shapes it was found that external face shape varies according to upper face dimensions and the shape of the chin, and that vertical featural configurations are strongly linked to external face shape. When the portrait and photograph data were placed in the same geometric morphometric analysis the inaccuracies in the portrait drawings became evident. When these findings were compared to the visual assessments it transpired that, on average, visual assessment was generally congruent with the geometric morphometric analysis, but were possibly confounded by patterns of dysmorphology in the portraits that were contrary to what this study suggests are normal patterns of face shape variation. Overall this study has demonstrated that while anthropometric and visual assessments of facial differences are quite good, both were comparatively poor at assessing head pitch and tended to be confounded by the dysmorphologies arising in the portrait drawings. Geometric morphometric analysis was found to be very powerful in discerning complex shape variations associated with head pose and individual differences in facial morphology, both within and between the photographs and portraits.