A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, for the Degree of Doctor of Philosophy. / The comparative structure of the diencephalon was investigated in the elephant shrew, the tree-shrew and several of the prosimian and anthropoid primates, including man. The brains were perfused with and fixed in formol saline. Most of those brains were sectioned transversely; others horizontally and sagitaliy. Sections of the diencophalon were stained with the cresyl-echt violet method for cytology and the study of cytoarchitectonics, and with the Kluver and Barrera, and Simmons techniques for myeloarchitectonics. / WHSLYP2017

Aspects of olfactory, auditory, visual and tactile communication were investigated in five Elephantulus species (E. brachyrhynchus, E. edwardii, E. intuft, E. myurus, E. rupestris) and Macroscelides proboscideus, facilitating comparisons among species and genera. The purpose of this study was to determine whether species specific patterns of communication could be identified in the southern African elephant-shrews. Scent gland structure and location was investigated to determine whether species specific differences existed and to relate gland location to marking behaviour. Prominent scent glands were found in the oral angel, foot pads, anogenital region and tail of all elephant-shrew specIes. Marking behaviours such as sandbathing, digging and anal dragging correlated strongly with sent gland location, but no glandular size and/or structural differences were apparent among the different elephant-shrew species. Species specific differences in marking frequencies did exist among the six elephant-shrew taxa, but were unrelated to glandular development. Choice chamber preference tests indicated that Elephantulus species preferred conspecific odours, with males showing higher levels of discrimination than females . Audible vocalizations and footdrumrning were investigated and compared in the sex elephant shrew taxa. Distinct differences were present in the acoustic repertoires of the southern African elephant-shrew species. Footdrumming showed very clear species specific patterns, and footdrumming characteristics were compared with an existing morphological phenogram to derive a possible path of evolution for footdrumming. Visual and tactile communication were investigated by analysis of frequencies and sequences of behavioural acts. A comparison of male-female interactions of the different taxa showed differences in behavioural frequencies both between males and females of a species, and among the different species. Discriminant function analysis showed clear species specific patterns in the visual! tactile signalling systems of southern African elephant-shrews, and this was more clearly defined in males. Elephant-shrews showed higher levels of aggressive behaviour in interspecific encounters, indicating a possible role of aggression as a premating isolating mechanism between species. However, no differences in aggressive behaviour between allopatric and sympatric malefemale interactions could be discerned. Elephant-shrew males showed high frequencies of submissive behaviour in intraspecific encounters, which may be a strategy to reduce aggression in conspecific females. Species specific patterns of behaviour were found to exist in all three modes of communication investigated, and may all act to some extent as premating isolation mechanisms between species. However, many of these patterns are very subtle and it is suggested that a combination of all sensory modalities act together to form each species' signalling system. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1996.

Eremitalpa granti namibensis is a small blind subterranean insectivore (Chrysochloridae) endemic to the Namib Desert sand dunes. This study of the biology and ecology of the Namib mole assesses its adaptive strategies for survival in a harsh environment. Major areas of study include feeding ecology, movement patterns, home range, activity, thermoregulation and water metabolism. Diet of free-living moles was assessed through stomach content analysis while qualitative and quantitative descriptions of surface foraging paths related searching behaviour to resource abundance and distribution. Moles opportunistically fed on termites, a sedentary prey resource occurring in patches of high concentrations while non-random surface locomotion minimised foraging costs. Population density and home range utilisation were studied by following surface trails and capture mark and recapture. Population density was low but stable and home range size large. No permanent nests or burrows were found while the pattern of home range utilisation was nomadic but circumscribed. Although ranges overlapped, a system of mutual avoidance limited encounters with neighbouring animals. Activity phasing was examined in the field and in the laboratory. Free-living moles were almost exclusively nocturnal while captive moles were active day and night. These findings are discussed in relation to prey availability, predator pressure and avoidance of diurnal extremes. Light and temperature appeared to be important cues for daily onset and cessation of activity. Aspects of thermoregulation examined under laboratory and field conditions revealed high thermal conductance, a low basal metabolic rate and poor thermoregulatory abilities. Factors suggested to have selected for these traits are the gaseous regime of the sand in which moles burrow and the need to minimise energy expenditure in an energy sparse environment. Laboratory and field studies employing isotopic dilution of energy and water methods e xamined the metabolism ability of moles to survive on an insect diet without drinking water. Water independence was achieved through efficient renal function while low rates of energy usage and torpor were further effective in reducing overall water requirements. In summation, a broad overview of adaptive radiation in Namib moles compared to other subterranean mammals is discussed. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1989.