The following is a detailed study of two allied intrusions of Karroo dolerite, situated in the Matatiele district of East Griqualand (South Africa). The one intrusion is a multiple dike of exceptional form and great length. It served as the main feeder of the second intrusion, a thick transgressive sheet. Two magmas contributed to the formation of the dike. A first intrusion of tholeiite magma was followed by the injection of a large volume of olivine-dolerite magma. The tholeiitic phase is absent in the sheet, which only contains the cooled representatives of the olivine-dolerite magma. A considerable degree of magmatic differentiation in the latter magma has led to the production of a great variety of rock types. In the dike such types are represented by picrites and olivine-dolerites, whereas the dolerites of the sheet range from olivine-bearing types to rocks, rich in soda and iron. Such variability is found to be consistent with processes of differentiation, involving gravitational settling of olivine and marked crystal-fractionation. The dike is roofed, and its behaviour recalls the characters of the Cleveland dike in northern England. Evidence is forwarded, suggesting that the dike possesses a floor as well as a roof. Both the tholeiite- and the olivine-dolerite magma were very active in their behaviour towards the associated sediments. The tholeiite magma mobilised and reacted with the Molteno sediments of the dike-walls. In the sheet a blcok of Burghersdorp sandstone was metasomatised by emanations derived from Olivine-dolerite magma. As a result a well-defined band of pale granophyric rocks was produced. Chemical and mineralogical data are given and the inferences drawn are applied to the general problem of the mode of intrusion and the differentiation of the Karroo magma.

Thesis (M.S.)--University of Pretoria, 2007. / Title from PDF title page (viewed on Nov. 12, 2008). Includes bibliographical references.

Thesis (MSc (Veterinary Science))--University of Pretoria, 2005. / Includes bibliographical references.

Thesis (M.S.)--Georgia Southern University, 2004. / "A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Vita. Includes bibliographical references (p. 48).

A Research Report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg in partial fulfilment of the requirements for the degree of Master of Science. Johannesburg, February 2013. / The degree that different landscape features influence elephants use of space in the Kruger National Park and surrounding private game reserves (Balule, Timbavati, Klaserie and Umbabat) is not known. The aim of my study was to assess landscape features which influence elephant space use at two different spatial scales: at a large scale representing home range selection within the landscape and a small scale representing core area selection within the total home range. I investigated the space use of 15 male and 6 female adult elephants over a three year period (June2007-May 2010), using GPS data and satellite mapping analysis. The features selected for analysis as possible barriers to elephant space use were anthropogenic (fences, roads, railway lines and infrastructure) and natural features (rivers, geological features and vegetation). I also investigated the total and core home range size of elephants and whether elephant space use differed by sex and season. Males had larger total home ranges than females irrespective of season, but there were no size or seasonal differences of core home range size between the sexes. Elephants used features differently at the two spatial scales, differed in the use of features between seasons, and there was a difference between the sexes in the use of features. Fences, railways, rivers (in the wet season), geological features and vegetation types were the features that influenced elephant space use, and could be possible barriers at the large scale. Elephants occurred close to fences which possibly restricted their space use. Elephants also occurred close to railway lines but they might not have crossed the railway line. As expected elephants occurred less often at close distances to rivers in the wet season which could possibly be as a result of higher rainfall in this season, preventing elephants from crossing their usual riverbed corridors. Male and female elephants differed in the use of vegetation types found on particular geological features: males selected basalt and females selected granite areas for both the dry and wet seasons. Both male and female elephants were associated with a wider variety of vegetation types in the dry season, possibly because the limited food availability causes elephants to cover larger areas in search of food. Elephant space use was therefore governed by several features that may or may not restrict space use. My study, using satellite mapping analysis, can suggest what hinders movements of elephants and what is essential for assisting elephant space use, which could help conservation efforts for reserve design and corridor formation between reserves.

In this research report I address the question: Is it ever morally justified to cull elephants? And, if it is, what criteria need to be fulfilled for a cull to be morally justifiable? In answering the first part of the question, ‘Is it ever morally correct to cull elephants?’ I defend the claim that the killing of elephants is a pro tanto wrong. The second part of the question, ‘What criteria need to be fulfilled for a cull to be morally justifiable?’, directs my attention to identifying conditions under which the pro tanto wrong of killing elephants could be outweighed by other moral considerations. I identify and critically discuss these criteria, developing what I call a ‘Theory of a Just Cull’. Finally, I apply my Theory to the current situation in South Africa, and argue that it is not possible to ethically justify elephant culling in South Africa in the current circumstances.

A thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy / African elephants are one of the iconic mammalian species of the continent, and are the largest terrestrial mammals on the planet. While being a well-known species, with intensive behavioural studies having been undertaken, studies of the elephant brain are limited. Given that elephants do show a unique and interesting set of behaviours, including infrasonic communication, unique control of the trunk, and that they eat around 500 kg of low quality plant matter each day, the current study aimed to investigate the neural underpinnings of these and many other behaviours exhibited by elephants. While not all aspects of elephant neuroanatomy are covered in the current set of studies, the results have provided a great deal of data for regions of the brain that have not been examined for almost 50 years, and applied modern neuroanatomical methods to this task. This thesis outlines how to obtain elephant brains amenable to modern neuroanatomical study, demonstrates that the ventricles are of a size predictable for a mammal with a 5 kg brain, and that the cerebellum is relatively the largest mammalian cerebellum studied to date. A microscopic examination of the cerebellar cortex revealed that the elephants have a greater amount of a potentially more complexly organized cerebellar cortex. In addition, an architectonic study of the diencephalon and brainstem revealed that elephants, while having a mostly standard mammalian diencephalon and brainstem, do show unique features that correlate to control of specialized behaviours. In summary, the current study shows that the system for motor timing, infrasound production and reception, and the systems for satiety and wakefulness are specialized in the elephant, all of which correlate to the overt behaviours previously studied. In addition, the current studies indicate potential paths to follow for the study of behaviour in these species that will hopefully lead to a better understanding of these animals. There is still much to explore and learn about the elephant brain and it is hoped this thesis creates a platform that provides the impetus for many future studies

Prolactin (PRL) is a peptide hormone that is involved in a number of diverse physiologic roles, particularly with respect to reproduction, including: influencing sexual and parental behaviors, onset of puberty, regulation of seasonal reproduction, follicular maturation, ovulation, luteinization and corpus luteum (CL) function, steroidogenesis, mammary gland development and lactation, testicular and spermatozoal function, and immunomodulation of ovarian processes. Little is known about PRL's role in elephant reproduction. The present research was conducted to determine seasonal changes in PRL secretion in non-pregnant female African elephants. A corollary objective was to examine the potential functional interrelationships between secretions of PRL, cortisol and progesterone. Weekly blood samples for 18 months were taken from four female African elephants and the sera were analyzed by radioimmunoassay for progesterone, cortisol, and PRL concentrations. Estrous cycles averaged 14 weeks in length, and estrous cycle synchronicity was evident between pairs of elephants. The luteal phase was defined by serum concentrations of progesterone consistently above 200 pg/ml, and averaged 9 weeks in length (range: 5-12 weeks) with a mean (�� SE) concentration of 750.3 �� 171.9 pg/ml. The follicular phase was defined by serum concentrations of progesterone consistently below 200 pg/ml, and averaged 5 weeks in length (range: 4-8 weeks) with a mean concentration of 103.1 �� 17.5 pg/ml. Mean (�� SE) serum concentration of cortisol was 5.7 �� 1.3 ng/ml (range: 1.4-19.3 ng/ml), and concentrations of this adrenal steroid were negatively correlated with progesterone concentrations (r=-0.15; p<0.01). Serum concentrations of PRL averaged 3.91 �� 0.69 ng/ml (range: 0.84-15.8 ng/ml), were significantly lower during the luteal phase (p<0.0001; t-test), and were positively correlated with serum concentrations of cortisol (r=0.14; p<0.05). There was no significant effect of season on PRL concentrations. One of the elephants appeared to be hyperthyroid, but since removing her values from the data set did little to affect overall means, they were included in all of the calculations. These data suggest that stress may affect secretion of PRL in elephants, and cortisol and PRL may affect reproductive potential in elephants by altering luteal function. While this study did not demonstrate a seasonal effect on PRL secretion, it cannot be concluded that there is none because the reproductive effects of photoperiod are not always easy to detect. The higher serum concentrations of PRL detected during the follicular phase suggest that this hormone may play a role in modulating ovarian function in elephants during this stage of the estrous cycle. / Graduation date: 1998

It has been suggested that African savanna elephants Loxodonta africana produce 31 different call types (Langbauer 2000). Various researchers have described these calls by associating them with specific behavioural contexts. More recently Leong et al. (2003) have attempted to classify elephant call types based on their physical properties. They classified 8 acoustically distinct call types from a population of captive elephants. This study focuses on one of these call types, the rumble, in a wild population of elephants in Kruger National Park, South Africa. A single family group of elephants was followed to record group behaviours and vocalizations from January through August 2001. By measuring the physical properties of 663 rumbles and subjecting these to cluster analysis, we present evidence that shows that rumbles can be categorized by their physical properties and that the resulting rumble types are associated with specific group behaviours. We characterize three types of rumbles that differ significantly by ten acoustic parameters. Two rumble types were associated with the elephant group feeding and resting, while the third was associated with socializing and agitation.

Thesis (M.F.A.)--San Jose State University, 2005. / Includes abstract. Includes bibliographical references (leaf xviii). Subscription required for access to full text. ProQuest ; Also available via the World Wide Web ;