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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

A knowledge-based system for hominid fossils

Cooper, Robert D. January 2004 (has links)
Thesis (M.S.)--University of Florida, 2004. / Title from title page of source document. Document formatted into pages; contains 77 pages. Includes vita. Includes bibliographical references.
22

Laetoli Pliocene paleoecology : a reanalysis via morphological and behavioral approaches /

Musiba, Charles M. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Anthropology, December 1999. / Includes bibliographical references. Also available on the Internet.
23

Paleoecological reconstructions of the South African Plio-Pleistocene based on low-magnification dental microwear of fossil primates

Carter, Brian D. January 2006 (has links)
Thesis (M.A.)--Georgia State University, 2006. / Title from title screen. Frank L. Williams, committee chair; Cassandra White, Susan C. McCombie, committee members. Description based on contents viewed June 25, 2007. Includes bibliographical references (p. 89-99).
24

The use of convergence as a tool in the reconstruction of human past, with special focus on water use in hominin evolution

Bender, Pedro Renato 06 February 2015 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2014. / In the present thesis the use of convergence as a tool in functional analyses was investigated, with special focus on comparisons using distantly related species (“convergence approach”). Guidelines for the convergence approach were forumlated and applied in the evaluation of selected hypotheses on the contextualization of early hominins. Additionally, comprehensive reviews on water use in primates were carried out, with special focus on hominoids, including humans. The first description (and video footage) of swimming and diving behaviour in a common chimpanzee (Pan troglodytes) and an orangutan (Pongo pygmaeus) were presented here, along with swimming behaviour in other great apes (without video footage). Hypotheses on the loss of instinctive swimming in hominoids were discussed and the Saci last common ancestor hypothesis was proposed. This model suggests that the loss of swimming ability in hominoids is best explained as a consequence of phylogenetic constraints linked to the adaptation to an arboreal life in the last common ancestor of this taxon. Furthermore, several hypotheses on early hominin evolution were reviewed. It was pointed out that several of these hypotheses have similar methodological flaws in the use of analogies to corroborate specific arguments. A hypothesis on the emergence of the habitual bipedalism in early hominins was outlined, arguing that this trait did not evolve in association with a locomotory advantage or for other reasons usually presented in the literature, but as a signal to advertise unprofitability – as a warning signal in an anti-predator strategy. It was argued that fossil evidence does not allow a high resolution of inference concerning incipient traits – traits which are not optimized to fulfil a certain function after a functional change. The consideration of different lines of evidence presented in this thesis indicate that the topic “water use” must be considered in discussions on early hominin evolution. The fact that humans regularly and intensively interact with water can be considered as an indication that in some part of human phylogeny after the hominin/panin split, swimming and diving ability was specifically selected. However, contrary to the view of several proponents of the aquatic hypotheses, it was demonstrated that humans are not absolutely unique concerning their ability to learn to swim and to dive. It is therefore also conceivable that our ability to learn to swim is associated to our cognitive abilities and is not a product of specific selection in our past.
25

A morphometric analysis of hominin teeth attributed to different species of australopithecus, paranthropus and homo

Dykes, Susan J. 02 February 2015 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, October 29, 2014. / Teeth are the most common element in the fossil record and play a critical role in taxonomic assessments. Size, relative width and cusp arrangements on enamel crown surfaces are used to help assess relationships between specimens. In this exploratory study, a model is developed for the placement of landmarks on images of lower first molars to maximise key information from crown surfaces of molars of African Plio-Pleistocene hominin fossils representing species of Australopithecus, Paranthropus and Homo. Lower first molar data of four extant species (Pan paniscus, Pan troglodytes, Gorilla and Homo sapiens) are visualised in a principal components analysis to detect whether landmark placements are adequate to identify species groupings and overlaps and patterns indicative of sexual dimorphism. The role of size as a differentiator between extant species is visualised using Procrustes Form Space as the basis for the analysis. A series of analyses, including linear diameter plots, Procrustes averaging, principal components analyses, discriminant function analyses and log sem (based on regression analyses) are used to test whether species groupings agree with currently accepted taxonomic classifications of thirty-six African Plio-Pleistocene hominin lower 2 first molars. Specimens in the sample that consistently fail to group with current species designations are flagged as “anomalous”. Six specimens are identified as anomalous and these are ultimately removed from the analyses. The resultant principal components plot of the fossil specimens appears to show distinctions between currently accepted species groups. The statistical regression analyses (log sem) confirm the results from the geometric morphometric analyses, and are associated with an average log sem value of -1.61 for conspecific pairwise comparisons. The log sem value of -1.61 has been proposed by Thackeray (2007a) as an approximation of a biological species constant (T), based on pairwise comparisons of modern vertebrate taxa, using cranial data. The anomalies confirm the hypothesis that certain specimens from the sample may have been misclassified, and that certain species groups as currently defined may comprise more than one morphotype.
26

A critical assessment of southern African 'early hominid bone tools'

Backwell, Lucinda Ruth 10 March 2014 (has links)
Thesis (M.Sc.)--University of the Witwatersrand, Faculty of Science, 2000.
27

Cladistic analysis of juvenile and adult hominoid cranial shape variables / The role of ontogeny for reconstructing hominid phylogeny

Unknown Date (has links)
Phylogenies constructed from skeletal data often contradict those built from genetic data. This study evaluates the phylogenetic utility of adult male, female, and juvenile hominoid cranial bones. First, I used geometric morphometric methods to compare the cranial bone shapes of seven primate genera (Gorilla, Homo, Hylobates, Macaca, Nomascus, Pan, and Pongo). I then coded these shapes as continuous characters and constructed cladograms via parsimony analysis for the adult male, female, and juvenile character matrices. Finally, I evaluated the similarity of these cladograms to one another and to the genetic phylogeny using topological distance software. Cladograms did not differ from one another or the genetic phylogeny less than comparisons of randomly generated trees. These results suggest that cranial shapes are unlikely to provide accurate phylogenetic information, and agree with other analyses of skeletal data that fail to recover the molecular phylogeny (Collard & Wood, 2000, 2001; Springer et al., 2007). / by Thomas A. DiVito, II. / Title of the abstract: The role of ontogeny for reconstructing hominid phylogeny. / Thesis (M.A.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
28

The Paranthropus face: examining a developmental model

Unknown Date (has links)
The Paranthropus head is characterized by features traditionally thought to be related to heavy chewing. McCollum [Science 284 (1999) : 301-305] proposed that palatal thickening is a response to developmental integration between the mandibular ramus, oral and nasal functional matrices, and the vomer, which inserts onto the premaxilla in Paranthropus and causes the palate to thicken instead of rotate during vertical expansion. I tested whether palate thickness increases as a byproduct of differential increases in the sizes of the oral and nasal functional matrices compared to growth in the mandibular ramus. To do so, I collected 3D volume and landmark data from computed tomography (CT) scans of extant (Homo sapiens, Pan troglodytes, Gorilla gorilla, Pongo pygmaeus) and extinct taxa (Australopithecus and Paranthropus), and tested counterpart relationships for bones in the cranium using scaling analyses. Results suggest that developmental constraints related to growth counterpart relationships in the skulll are unlikely to affect palate thickness in the genus Paranthropus. / by Brittany A. Burdelsky. / Thesis (M.A.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
29

The timing of growth spurts in Neanderthals

Unknown Date (has links)
The timing of skeletal growth spurts in modern humans is unique among mammals. In modern humans, peak growth occurs after puberty during the adolescent period, whereas large-bodied non-human primates exhibit an earlier juvenile growth spurt. Based on limited data, previous researchers have suggested that Neanderthals experienced a late, modern human-like adolescent growth spurt. In this study, I examined the timing of stature and facial growth spurts in Neanderthals to test the hypothesis that Neanderthals grew like modern humans. In order to assess the timing of Neanderthal growth spurts, I plotted a non-human primate regression estimate of age at puberty onto Neanderthal stature and mandibular velocity growth curves. The mandibular growth curve exhibits a discernible growth spurt after puberty, reminiscent of the modern human adolescent growth spurt. Future research on additional regions of the skeleton is necessary to further refine this estimate for the timing of Neanderthal growth spurts. / by Amy C. Lupo. / Thesis (M.A.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
30

Thoracic and lumbar vertebrae of African hominids ancient and recent: morphological and fuctional aspects with special reference to upright posture

Benade, Maria Magdalena 18 July 2016 (has links)
A Dissertation Submitted to the Faculty of Science University of the Witwatersrand, Johannesburg for the Degree of Master of Science January, 1990 / This is a study of the morphological and functional aspects of A. africanus thoracic and lumbar vertebrae in comparison with those of modern human and anthropoid ape vertebrae. The purpose is to determine if any derived features in the morphology of hominids, as distinct from primitive features shared with non-hominids, were present and if so to what stage of attainment of full erectness such features point. The major results of this study are as follows: (i) There is a difference in the configuration of the lumbar articular facets between pongids, on the one hand, and modern human and A. africanus, on the other hand. This difference suggests that similar stresses operate in these regions in the two hominid groups. (ii) Bony adaptation to a developed lumbar lordosis is present in A. africanus. (iii) Major agreement has been found in the relative dimensions of modern human and A. africanus lumbar vertebrae, in contrast to those of pongid vertebrae. This indicates probable correspondence in the pattern of weight transmission to the pelvis in modern humans and A. africanus. (iv) The decrease of inferior lumbar vertebral body area starts at higher levels in sts 14 (an A. africanus partial skeleton) than in modern man, suggesting a longer curved lower lumbar region in A. africanus. From these results it may be concluded that the trunk was probably carried in a fully erect posture in A. africanus. The bony adaptation thereto, however, may not have been fully developed as in modern man. It is proposed that, in Sts 14, the last two lumbar vertebrae were carried at an angle relative to each other and to the sacrum, in contrast to the abrupt change in direction between L5 and the sacrum in modern man.

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