This thesis uses metrical data and morphological observations to describe the comparative anatomy of the cranial base region in extant adult hominoids. The changes that occur during growth in this region have also been studied in samples of juvenile hominoids, and cross-sectional growth data for the same variables measured in the adult metrical study have been recorded. Detailed metrical and morphological observations were also made on a series of fossil hominid crania dating from the Plio- Pleistocene. The results of the two comparative studies of the cranial base region in extant hominoids were then used to assess the significance of the differences noted in the cranial base region of the fossil hominids from sites in South and East Africa. The results of the adult metrical study; and the series of soft tissue dissections, demonstrate that there are fundamental differences in the comparative anatomy of the modern human and pongid cranial bases. The results of the comparative growth study indicate that these differences are probably not the result of an overall acceleration, or retardation, in growth rates of the component bones of the human cranial base, but more likely due to a combination of increases and decreases in growth rates occurring in individual bones, as well as to differences in morphology already manifest soon after birth. The results of the study of fossil hominid specimens indicate that the 'gracile' australopithecine fossils from South Africa have a cranial base pattern similar to that of the extant pongid samples, but that the 'robust' australopithecine fossils, and those fossils attributed to early Homo have a cranial base pattern more similar hominid fossil specimens which are still of uncertain taxonomic designation. The comparative studies of the hominoid cranial base also provide a framework which enables features of this region to be used in phylogenetic analysis. to the modern Homo sapiens sample. These differences in basicranial anatomy among the fossil hominid sample provide a useful tool to assess the taxonomic status of several
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:389071 |
| Date | January 1982 |
| Creators | Dean, Michael Christopher |
| Publisher | University College London (University of London) |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://discovery.ucl.ac.uk/1381921/ |
Page generated in 0.0018 seconds