Recently, the number of hominin genera has increased dramatically. Prior to the announcement of Ardipithecus, only two genera were used by paleoanthropologists: Australopithecus and Homo. Presently, up to eight hominin genera are used: Sahelanthropus, Orrorin, Ardipithecus, Australopithecus, Praeanthropus, Kenyanthropus, Paranthropus and Homo. Unlike species concepts, the genus category has not received wide critical examination. To investigate the use of the genus category in paleoanthropology, a comparative framework drawing on morphometric data from a large number of catarrhines is developed. Cranial variables include 36 standard linear measurements from representatives of catarrhine genera across the major tribes/families. This study seeks to assess whether too few or too many hominin genera have been recognized compared with extant catarrhines. Moreover, two published hypotheses about the use of Homo are examined: 1) Wood & Collard's (1999) proposal to transfer Homo habilis/rudolfensis to Australopithecus; and 2) Goodman et al's (1998) classification of both humans and chimpanzees in Homo. To analyze these cranial variables and a number of shape indices calculated from them, as well as to assess competing hypotheses, univariate, bivariate and multivariate statistical approaches are used. The results allow the identification of a set of variables and shape indices which distinguish genera across the catarrhines. Importantly, body size seems to be the major separator of catarrhine genera, reinforcing the idea that they occupy discrete adaptive zones. Moreover, differences between these genera mostly represent contrasts in the size of the neuroversus the viscerocranium. When applied to hominins, a picture emerges which distinguishes them from extant catarrhines: cranial shape rather than size is the major component distinguishing them; this suggests that extinct hominins occupied similar habitats and adaptive zones; variability in size and shape within hominin genera is much lower than extant catarrhines; and the major differences seen in shape among hominins are the result of encephalization in Homo. It is concluded here that both Wood & Collard's (1999) and Goodman et al.'s (1998) proposals appear to be premature. Moreover, while the earliest hominins may be too finely split at the genus level, the evidence for distinction of Australopithecus and Paranthropus is solid.

Recently, the number of hominin genera has increased dramatically. Prior to the announcement of Ardipithecus, only two genera were used by paleoanthropologists: Australopithecus and Homo. Presently, up to eight hominin genera are used: Sahelanthropus, Orrorin, Ardipithecus, Australopithecus, Praeanthropus, Kenyanthropus, Paranthropus and Homo. Unlike species concepts, the genus category has not received wide critical examination. To investigate the use of the genus category in paleoanthropology, a comparative framework drawing on morphometric data from a large number of catarrhines is developed. Cranial variables include 36 standard linear measurements from representatives of catarrhine genera across the major tribes/families. This study seeks to assess whether too few or too many hominin genera have been recognized compared with extant catarrhines. Moreover, two published hypotheses about the use of Homo are examined: 1) Wood & Collard's (1999) proposal to transfer Homo habilis/rudolfensis to Australopithecus; and 2) Goodman et al's (1998) classification of both humans and chimpanzees in Homo. To analyze these cranial variables and a number of shape indices calculated from them, as well as to assess competing hypotheses, univariate, bivariate and multivariate statistical approaches are used. The results allow the identification of a set of variables and shape indices which distinguish genera across the catarrhines. Importantly, body size seems to be the major separator of catarrhine genera, reinforcing the idea that they occupy discrete adaptive zones. Moreover, differences between these genera mostly represent contrasts in the size of the neuroversus the viscerocranium. When applied to hominins, a picture emerges which distinguishes them from extant catarrhines: cranial shape rather than size is the major component distinguishing them; this suggests that extinct hominins occupied similar habitats and adaptive zones; variability in size and shape within hominin genera is much lower than extant catarrhines; and the major differences seen in shape among hominins are the result of encephalization in Homo. It is concluded here that both Wood & Collard's (1999) and Goodman et al.'s (1998) proposals appear to be premature. Moreover, while the earliest hominins may be too finely split at the genus level, the evidence for distinction of Australopithecus and Paranthropus is solid.

Thesis (Ph.D.)--University of the Witwatersrand, Faculty of Science (Anatomical Sciences),1998.

Thesis (Ph. D.)--University of Chicago, Dept. of Anthropology, March 2001. / Includes bibliographical references. Also available on the Internet.

The thoracic skeletal morphology of homininae is poorly known and understood. As a result of the representative fossil record of ribs and vertebrae being rare, distorted, fragmentary or unrecognised even when recovered, very little is known about the variability of rib and vertebral morphology when compared to the other cranial and postcranial elements in this lineage. Yet the costal skeleton forms a substantial part of the postcranial skeleton and thus ribs and vertebrae are therefore potentially numerous in the fossil record; but in comparison with other skeletal elements, and for the reasons mentioned above, very little is known about vertebrate and especially hominin rib morphology. The assessment of the structure of the thoracic skeletal elements and its evolutionary and ecological significance, particularly in the Homininae, poses a challenge but is still important as the shape and form of the rib cage has numerous functional and behavioural implications. The present study analysed the ribs of selected primate and non-primate mammalian species by examining fifteen variables, seven indices and eight osteological non-metric features. These observations and measurements were compared to ribs found in the fossil record in order to determine if there are any structural correlates between the extant and the extinct hominin and mammalian species and in order to create a template for the identification of hominin ribs within an abundant and diverse mammalian assemblage. The results suggest that the 1st rib, due to its unique morphology, may be considered most diagnostic in differentiating various taxa. In addition, a template for the morphology of the proximal end of the first rib has been created to be used for both the general as well as the specific identification of fossilised fragments, and to determine thoracic shape. The recently recovered costal elements of the Australopithecus sediba fossils were also examined as one of the most abundant assemblages of the elements in the early hominin record in order to add to our understanding of the morphology, and evolution of this poorly known area of hominin anatomy. The thorax of Australopithecus sediba demonstrates a medio-laterally narrow, ape-like upper thoracic shape, which is different from the broad upper thorax of Homo that has been associated with to the locomotor pattern of endurance walking and running. The lower thorax, however, is less laterally-flared than that of apes, and more closely approximates the morphology found in humans. This indicates a mosaic morphology of the thorax during the human evolutionary linage.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 187-110). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 187-110). Also available on the Internet.

Thesis (Ph.D.)--Kent State University, 2008. / Title from PDF t.p. (viewed Oct. 8, 2009). Advisor: C. Owen Lovejoy. Keywords: lumbar transverse process; vertebral evolution Includes bibliographical references (p. 214-221).

Thesis is submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Science, School of Geosciences, University of the Witwatersrand, Johannesburg, 2018 / Teeth make up the bulk of hominin fossil material and are useful in taxonomic assessments. In this thesis, discriminant function, principal components and randomised CV analyses on large samples of lower second molars (n=778) from five extant reference species, both sexually dimorphic and non-dimorphic, provide estimates of ranges of size-shape variability to be expected within a single species. However, there is evidence that diet-driven tooth-size reduction and cusp simplification has expanded the ranges of shape and size variability of Homo sapiens in some populations, in areas exposed to soft, undemanding diets since the transition to agriculture and increased use of cooking, food processing and ceramics from about 12500 years ago. Molar size and shape changes are less evident in communities retaining a hunter-gatherer subsistence strategy, requiring strong dentognathic structures with robust teeth to masticate harder, tougher foodstuffs. These factors, driving divergent variability in tooth size and shape, are unique to modern humans. Using a novel mathematically-based landmarking methodology, developed to allow the inclusion of severely worn teeth, intra-species size-shape variability was assessed from 63 lower M2s representing nine African Plio-Pleistocene species. The first hypotheses tested in this thesis address the question of which extant hominoid species might be suitable for use as analogue species for comparisons with fossil hominin molars, and whether uniquely modern-human anomalous size-shape variability exhibited by lower second molars might disqualify modern Homo sapiens for such analyses. Secondly, where lower second molar size-versus-shape variability ratios measured for fossil species do not match those of either a sexually dimorphic or a non-dimorphic extant species, evaluations are made as to whether samples attributed to single hominin species might actually represent specimens from more than one species present in the relevant assemblages, whether sexual dimorphism may have been greater in fossil species than in extant species, and whether some individual specimens attributed to any fossil species might be misclassified. Results of the analyses indicate that uniquely human subsistence strategy divergences are identifiable in the size-shape variability of lower second molars. Furthermore, specimens representing Australopithecus afarensis, Australopithecus africanus and Paranthropus robustus in this study exhibit very high variability and may indicate the presence of more than one species in their respective assemblages. / EM2018

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