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Call number: LD2668 .T4 1963 S63 / Master of Science

Thesis submitted to the Faculty of Science at the University of the Witwatersrand, Johannesburg in fulfillment of the requirements for the Degree of Doctor of Philosophy. / The taxonomy of modern and fossil Hystricidae and the evolutionary history of the family has been reviewed, with particular reference to 203 undescribed South African specimens from the Transvaal australopithecine deposits and Cave of Hearths. After comparison with all contemporaneous fossil forms (only 10 of the 28 described fossil species seem valid) it was concluded that Xenohystrix crassidens Greenwood 1955, Hystrix makapanensis (Greenwood 1958) and H. africaeaustralis Peters 1852 are present at Hakapansgat Limeworks, whereas only the latter species is present at the remaining australopithecine sites, with the possible exception of a few tentatively referred specimens of H. makapanensis. There are insufficient grounds for erecting a distinct species for the fossil form of H. africaeaustralis present in the australopithecine deposits and the Cave of Hearths material is likewise referred to the modern species. The distribution and minimum numbers of individuals of porcupine species present in the different breccias of the five sites is detailed and a reconstruction of the skull and mandible of X. crassidens attempted. The environment, stratigraphy and potential ages of the source deposits is discussed; it is concluded that with the exception of Taung, the dates suggested by Partridge and Vrba agree with the limited evidence provided by the fossil Hystricidae. Numerous skull characters used in the diagnoses of new Hystrix were examined for variability within a single modern species (only 3 of the 77 extant species proved to be valid) and then tested for diagnostic significance by comparison with the remaining valid species. Special attention was paid to mandibular and dental characters, particularly the crown enamel pattern, but the only reliable diagnostic characters were found to be associated with the anterior part of the cranium, which is seldom preserved in fossil form. The sequence of tooth replacement, a method for identifying isolated teeth, methods for segregating specimens into growth stages, and a standard terminology have been outlined. A taphonomic study, attempting to determine the extent to which fossil porcupines may have been responsible for the accumulation of the Makapansgat Limeworks bone assemblage and for the manufacture of the bone tools described by Dart, was undertaken. Unlike the fossil assemblage porcupine bone accumulations are characterized by a high percentage of much-gnawed bones, a large average fragment size, a high proportion of intact shafts with the concomitant near-absence of bone flakes anci a low survival potential for the articular ends of all limb bones. Comparison showed that the damage done by porcupines differs from that evident on the corresponding skeletal elements from Makapansgat. It is concluded that fossil porcupines had very little to do with either the accumulation or fracture of the Makapansgat Limeworks bones. / Andrew Chakane 2018

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.

Thesis (M.S.)--Ohio University, August, 2009. / Title from PDF t.p. Includes bibliographical references.

Thesis (Ph. D.)--University of Chicago, Committee on Evolutionary Biology, June 2001. / Includes bibliographical references. Also available on the Internet.

No description available.

185 leaves : ill., photos., charts, graphs, 11 fold. charts in end pocket ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology, 1981