Craters formed by impact and volcanic processes are among the most fundamental planetary landforms. This study examines the morphology of diverse craterforms on Io, the Moon, Mars, and Earth using quantitative, outline-based shape analysis and multivariate statistical methods to evaluate the differences between different types of. Ultimately, this should help establish relationships between the form and origin of craterforms. Developed in the field of geometric morphometrics by paleontological and biological sciences communities, these methods were used for the analysis of the shapes of crater outlines. The shapes of terrestrial ash-flow calderas, terrestrial basaltic shield calderas, martian calderas, Ionian paterae, and lunar impact craters were quantified and compared. Specifically, we used circularity, ellipticity, elliptic Fourier analysis (EFA), Zahn and Roskies (Z-R) shape function, and diameter. Quantitative shape descriptors obtained from EFA yield coefficients from decomposition of the Fourier series that separates the vertical and horizontal components among the outline points for each shape. The shape descriptors extracted from Z-R analysis represent the angular deviation of the shapes from a circle. These quantities were subjected to multivariate statistical analysis including principal component analysis (PCA) and discriminant analysis, to examine maximum differences between each a priori established group. Univariate analyses of morphological quantities including diameter, circularity, and ellipticity, as well as multivariate analyses of elliptic Fourier coefficients and Z-R shape function angular quantities show that ash-flow calderas and paterae on Io, as well as basaltic shield calderas and martian calderas, are most similar in shape. Other classes of craters are also shown to be statistically distinct from one another. Multivariate statistical models provide successful classification of different types of craters. Three classification models were built with overall successful classification rates ranging from 90% to 75%, each conveying different shape information. The EFA model including coefficients from the 2nd to 10th harmonic was the most successful supervised model with the highest overall classification rate and most successful predictive group membership assignments for the population of examined craterforms. Multivariate statistical methods and classification models can be effective tools for analyzing landforms on planetary surfaces and geologic morphology. With larger data sets used to enhance supervision of the model, more successful classification by the supervised model could likely reveal clues to the formation and variables involved in the genesis of landforms.

Positive identification can be problematic if fingerprinting, DNA, dental history, etc. are no longer available. This may be possible through techniques such as facial approximation, but any form of craniofacial identification requires intimate knowledge of human craniofacial anatomy. Where children are involved, craniofacial changes due to facial growth further complicate matters and require knowledge of tissue thickness and variation in facial shapes. These have hardly been studied in children of African descent. The aims of this study were to provide data on tissue thickness and craniofacial proportions of South African Black and Coloured children and to document the lateral profile shape changes between the ages of 6 and 13 years. Tissue thickness was measured using cephalograms of South African children (n = 388). After digitizing the images, tissue thickness measurements were taken at 11 mid-facial landmarks from each image using the iTEM measuring program. Craniofacial proportions were assessed through assessing standardized anterior and lateral facial photographs of 1749 children. Measurements of facial features were taken using iTEM, from which 28 standard facial indices were calculated. For both tissue thickness and craniofacial indices comparisons between groups per age, sex and ancestry were statistically analyzed. In addition, geometric morphometrics were used to describe lateral facial shape changes and differences age, sex and ancestry (n = 800). The results showed that tissue thickness differences at lower face landmarks are more pronounced in age groups per ancestry as opposed to differences per age and sex. Facial profile per facial shape, class and ancestry showed differences at all landmarks. Craniofacial indices indicated that Coloured children have wider heads, foreheads and faces compared to Black children. The height of the nose and lower lip is longer in Coloured children compared to Black children. In Coloured children, mandibular height and lower face height is shorter in relation to total face height. Males have wider heads, foreheads, mandibles and faces compared to females. The degree of prognathism is dictated by ancestry and to a lesser extent by age and sex as findings showed that maxillary prognathism was more prominent in Black children, while mandibular prognathism were more pronounced in male children. South Africans have a relative concave lateral facial profile due to the maxilla and mandible being more prognathic than in North American children. Differences in lateral face shape between children of various ages, sexes and ancestral groups were visualized through the relative displacement of landmarks related to the forehead and lower face. The resultant differences in lateral facial profile can assist in more accurate estimation of age and ancestry of unknown children. This research created reference datasets for tissue thickness and craniofacial indices of South African children of Black and Coloured ancestry per age and sex that will be useful in the diagnosis of facial dysmorphology and for facial reconstruction / approximation of juvenile remains. It also shed more light on facial growth patterns in the various groups. / Thesis (PhD)--University of Pretoria, 2015. / tm2015 / Anatomy / PhD / Unrestricted

Dissertation solves the problem of the origin of the mandible from collection of Moravian Museum in Brno. Publications of authors working in the location Předmostí u Přerova since the year 1884 have been used to achieve this goal. Simultaneously records in the incremental books of MZM in Brno have been researched, unfortunately without success. Therefore research of the biological affinity of the mandible P30 with others gravettiens discovery has been accepted as well as variability of recent humans. For study we used methods of geometric morphometrics, which allows us better clarify shape discrepancies in comparison with standard analytic methods. Comparison of shape variability of the mandible we used 91 cranial CT exposures of the recent Czech population. We placed 42 landmarks to segmented 3D models of the mandible and we made a PCA analysis. To extend the argument for justifiability to incorporate studied sample among discoveries from Předmostí u Přerova we created file of linear proportions of the tooth crown based on available publications and our own measuring. Morphological study, shape analysis of the mandible and dimension of the teeth leads us to results that the mandible P30 in our study can really belong to the Gravettien Age. Key words: Mandible, Molars, Předmostí u Přerova,...

The pattern of wing venation in dragonflies (Odonata) bears a set of characters commonly used in systematics. The aim of this thesis is to identify the wing venation variability of dragonflies by various methods of geometric morphometric. The wing venation variability was examined on the level of suborder, family, species and also in respect to dimorphism through the principal component analysis (PCA), redundancy analysis (RDA) and centroid size. Data set consisting of images of 46 dragonfly species, belonging to 43 genera and 24 families was obtained from institutional entomological collections. The research carried out that Zygoptera have a large variety of wing contours. The wing venation variability of Epiprocta is shown primarily in the costa and node area. Between sexes there is no noticeable difference in shape or structure of the wing. The ratio between wing length and width and the pterostigma shape is dependent on dragonfly body size. Key words: Odonatoptera, Odonata, Epiprocta, Zygoptera, wing venation, variability, geometric morphometrics

A Blue-tongued skink ( Tiliqua gigas) is a rare exotic species which is very popular between breeders. Nevertheless, the social structure of this charismatic skink remains almost unknown. Because of its high aggressive- ness and difficulties connected with study in its natural habitat, experiments based on the odor discrimination looks like a good alternative for its bet- ter understanding. Our results revealed that the reaction on the odor is generally poor and is very individual. We observed the highest response of interest on odors produced throught dorsal parts of skin. The reaction on conspecific's odor did not lead to escape behavior. Behavioral analysis was complemented by morphological analysis of heads in T. gigas and T.scincoides. These species are divided into separate subspecies, which are formed by geographically distinct populations. We wondered whether it is possible to separate these populations by geometric morphometrics and whether this separation is consistent with phylogenetic studies. We found out that if the populations are united in bigger groups based on their congeniality they seem to be distinct according to the head shape. Our results also revealed the monomorphy in head shape. Unfortu- nately, it is very difficult to distinguish between sexes due to the absence of sexual dimorphism....

In skeletal studies of prehistoric populations of Chile’s semiarid north, it is common practice for physical anthropologists to visually categorize crania as dolichophallic and brachycephalic which are then attributed to cultures or time periods based on the observed shape. The validity of this classification is still debated and poses several questions regarding the prehistory of Chile. The goal of this study is to investigate the craniofacial variation in populations representing the Archaic period and Intermediate-Late periods of Chile’s semiarid north using morphometric analysis. The samples comprise two collections from the Museo Arqueologico de La Serena in La Serena, Chile. The Archaic period dates from 10,000 BC to 300 AC. The Intermediate-Late period dates from 900 AC to 1500 AC. The Archaic period included 87 crania, while the Intermediate-Late period included 78 crania. Cranial vault modification was practiced in all prehistoric populations, and modified individuals comprise ~4.6% of the Archaic period sample and ~74.4% of the Intermediate-Late period sample. Individuals observed to be dolichocephalic are associated with the Archaic period, while brachycephalic individuals are associated with the Intermediate-Late period. Previous studies have shown that individuals with intentional cranial modification, annular and tabular, exhibit predictable changes in the craniofacial complex due to compensatory growth and shape changes related to peripheral structures of the cranial vault. A form of tabular modification is seen in both periods included in this sample, with the Intermediate-Late period sample being dominated by this modification. All craniometric landmarks were recorded using a Microscribe™ 3D digitizer, with exclusion of mandibular landmarks. MorphoJ was utilized to analyze the geometric morphometric data. Coordinates using the Microscribe were recorded in order to investigate the differences in shape of the craniofacial complex between the two samples. Two separate analyses were performed, one with all landmarks recorded and one excluding landmarks prosthion, alveolon, ectomolare and zygion. The results of both Canonical Variate analyses and associated Mahalanobis Distance values (2.699 and 2.9316) indicates statistically significant differences (p<0.001) between the two samples. It is also evident that shape changes along CV1, increases in minimum frontal breadth, upper facial breadth, and nasal height, correspond with characteristics associated with brachycephalism and tabular cranial vault modification. The large range of variation of the Intermediate-Late period sample is speculated to be a result of multiple small populations moving toward the coast possibly due to a change in climate. These small populations exhibited various morphologies which were influenced by nonrandom environmental factors. The Mahalanobis distances of the different cultural groups also indicate statistically significant differences. This method has the potential to be used in conjunction with others to identify cultural context and significance of remains in archaeological contexts in Chile. In the event of repatriation acts this method could also be used to attribute individuals to corresponding cultures and be donated to the appropriate community or facility.

Wild canid populations exhibit different anatomical morphologies compared to domesticated dogs in North America. This is particularly important concerning archaeological sites, which may contain early domesticated species, for the proper identification of osteological remains. Previous studies have indicated domestic dogs exhibit a shorter rostrum accompanied by a crowded tooth row; however, none describe the overall complexity of these changes. Consequently, using a landmark-based geometric morphometric analysis, cranial morphological characteristics were examined in North American wild canids: the gray wolf (Canis lupus), coyote (Canis latrans), red wolf (Canis rufus), and the domestic dog (Canis familiaris). The shape and size of the cranium in lateral and ventral views were compared between the three wild species to the group of domesticated dogs. Wild canids clustered separately from the domestic group in all statistical analyses. Results indicate an expansion of the orbital region, a compression of the rostrum, and an overall warping in the shape and orientation of the skull. In domestic species, there is also a downward shift in the frontal portion of the skull accompanied by the braincase assuming a more upward position. This technique successfully depicted how slight changes in isolated areas of the cranium can have an impact on the overall shape and morphology of the skull. We presume these changes in cranial anatomy reflect the recent selective pressures domestic dogs have undergone since diverging from their wild ancestors.

The threespine stickleback (Gasterosteus aculeatus) is an important model for studying evolution. Sticklebacks are widely distributed in the northern hemisphere and inhabit freshwater, brackish, and marine waters. Anadromous and marine populations (hereafter marine) are assumed to be homogenous in space and invariant in time in their phenotypic characteristics, despite marine environments varying on regional and local scales. Recent studies suggest there is in fact genetic and phenotypic structure in marine sticklebacks, yet the ecological causes remain unclear. My goal was to assess trait variation in marine stickleback populations around Southern coastal British Columbia (BC), and to determine whether or not oceanographic and habitat characteristics explained this variation. The area around Vancouver Island was ideal because four distinct oceanographic regions surround the island with varying coastal habitat types. Between May-July 2019, I sampled ~600 sticklebacks from 15 sites. I then characterized trait variation using two-dimensional (2D) geometric morphometric analysis to compare individuals between oceanographic regions and coastal habitats. I focused on five traits: armour phenotype, head size, body size, head shape, and body shape. I chose these traits because they are ecologically important and well-studied in freshwater populations, where their ecological drivers are known. I found that marine sticklebacks did vary morphologically among and between regions and habitats, but the variation was not immediately related to environmental variation, nor obviously comparable to variation in freshwater populations. Sexual dimorphism was the largest source of variation in the data, a well-established finding. But oceanographic and habitat variables influenced differences between males and females. I concluded that marine sticklebacks offer abundant opportunities for expanding our knowledge of drivers of morphology in nature. / Graduate / 2022-04-11

The genus Castor is represented in Eurasia by Castor fiber, North America by C. canadensis, and has been in North America since the late Miocene. This study aims to assess whether morphology of Miocene-Pliocene C. californicus and extant C. canadensis are distinctly different. Specimens of Castor were compared using geometric morphometrics on cranial material and linear measurements of postcranial material. Species occurrence data were compared with past and future climate data to assess Castor distribution in North America through time. Results show that C. canadensis is highly variable in both cranial and postcranial morphology and C. californicus falls largely within the range of variation seen within the extant species. Past distributions match fossil occurrences of Castor, suggesting confidence in projected models. Morphological and distribution similarities between the two species suggest that they can be treated as ecological analogs, though evaluation of whether they are conspecific will require more data.

The paleobiology of the Pleistocene North American giant short-faced bear, Arctodus simus, has eluded paleontologists for decades. Its more gracile form has led past researchers to myriad intepretations of the locomotion and feeding ecology of this species. While earlier studies have focused on craniodental morphology and simple postcranial indices, it is forelimb morphology that represents a direct compromise between locomotor and foraging behavior. The study here uses traditional and 3D landmark morphometrics to more completely compare the 3-dimensional shape of the major forelimb elements and their muscle attachment sites between A. simus, extant ursids, and other carnivorans. Results herein agree well with previous studies and provide additional evidence for reduced abductor/adductor and supinator/pronator musculature, more restricted parasagittal motion, increased stride length, and lighter and more packed distal elements. Forelimb skeletal morphology therefore supports the hypothesis that A. simmus represents a bear in the early stages of cursorial evolution.