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A taxonomic and ecological study of the living and fossil hystricidae with particular reference to Southern Africa.Maguire, J. M. January 1976 (has links)
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
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