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With the continuous urban expansion, assessing how some species can survive in urban environments, particularly through modifying their behaviour, is becoming increasingly important. Urban wildlife can show phenotypic (e.g. behavioural) flexibility to exploit urban areas but it is also possible that they could seek refuges that match their phylogenetic niche requirements. The public’s perceptions of these “urban” species may also influence their success within urban centres. Using the rock hyrax, Procavia capensis, in Greater Johannesburg as a model species, I assessed the flexible and niche conservative hypotheses for its occurrence in urban areas. In particular, I investigated 1) the behaviour and flight initiation distance (FID; a measure of habituation to people) of rock hyraxes in warm (February and September) and cold (June and July) months at an urban site, Meyersdal Eco Estate, south of Johannesburg; and 2) the occurrence and public perception of rock hyraxes in Greater Johannesburg. At Meyersdal Eco Estate, three colonies were identified along an approximately 2km gradient of proximity to humans, from those living in a storm-water drain and gardens to a colony situated >100m from houses. The three colonies showed differences in behavioural patterns compared to a natural population located in the Mountain Zebra National Park, Eastern Cape Province. Although behaviours such as basking, sunbathing, travelling, grooming, and vigilance did not change between the colonies, feeding behaviour was greater and FID scores were shorter in the colony closest to people, indicating greatest habituation to people compared to the colony furthest from people, which showed reduced feeding behaviour and greatest FID distance. The intermediately situated colony showed intermediate levels of feeding and FID. The behaviour of rock hyraxes was not influenced by deterrents (boa, Boa constrictor constrictor, dung and wild garlic, Tulbaghia violacea) used at Meyersdal to keep rock hyraxes away from gardens. Rock hyraxes ate a variety of plants including grasses, forbs, shrubs, trees and succulents at each of the colonies, but the colony closest to people also ate a variety of garden plants which I did not observe at the two other colonies, including two species of wild garlic, T. violacea and T. simmleri. Within Greater Johannesburg, rock hyraxes occurred in the northern and southern suburbs, and appeared to avoid densely urbanized areas. Resource selection functions suggested rock hyraxes associated with rocky outcrops potentially conforming to the niche conservatism hypothesis, although they did not select for any particular landscape feature in the Greater Johannesburg environment. The public viewed rock hyraxes more positively than anticipated, with most suggesting that they were part of the urban biodiversity of Greater Johannesburg. In conclusion, rock hyraxes have modified their behaviour and habituated to people over surprisingly small spatial scales. Such behavioural flexibility over comparatively short distances is a novel finding. However, rocky outcrops are still important natural habitats to meet thermoregulatory and denning requirements, and are used to explore and exploit the urban environment. Because they are constrained by their thermoregulatory requirements, habitat analogues (e.g. storm water drains) might create opportunities to enter houses and gardens. Such flexible responses, which together with a tolerant public, might allow them to flourish in Johannesburg.

Animals in the Southern African sub-region are faced with unpredictable seasonal rainfall patterns and unpredictably low resource availability due to the influence of the El Nino Southern Oscillation System. This has led to conservative energetic traits in animals that offset the costs of maintaining homeostasis in the unpredictable environments they inhabit. One of these animals is the rock hyrax (Procavia capensis). Past research has looked at the thermoregulation of rock hyrax in the laboratory. Results indicated that rock hyrax had labile body temperatures that reached lethal levels at ambient temperatures above 39°C. Laboratory studies separate endogenous thermoregulation from behavioural thermoregulation and do not reflect the overall thermoregulatory potential of the rock hyrax in maintaining body temperatures. This study looked at the thermoregulation of rock hyrax in their natural environment. Body temperatures were measured in the field using Thermochron iButtons inserted into the intraperitonial cavity of the animals. Behavioural observations were also recorded on subgroups and individually marked animals. Rock hyraxes were exposed to large fluctuations in ambient temperatures and food availability during the course of this study. In winter, ambient temperatures ranged between 5-25°C and in summer between 18-42°C. Our results show that rock hyrax seasonally and daily altered both their physiological and behavioural thermoregulation to control body temperature efficiently. The physiological alterations observed in rock hyrax differed between winter and summer. During winter, when food availability was low, rock hyrax maintained body temperatures at a lowered level relative to summer. Body temperatures fluctuated to a greater extent during winter as a result of reduced body temperatures at night and increased body temperatures due to basking during the diurnal hours. During summer, rock hyrax displayed high body temperatures, which reached hyperthermic levels. This enabled rock hyrax to forage during midday hours since heat loads could be easily dissipated through passive conduction in the cooler rock crevices. Rock hyrax employed different behavioural patterns in winter and summer. It is proposed that rock hyraxes are unable to meet energetic demands on a low quality and patchy food resource under low ambient temperatures. Predation is also a cost to foraging and becomes increasingly important when rock hyraxes have to move large distances away from crevices to find food. The most frequent behaviour recorded in rock hyrax during winter was basking. Basking enabled rock hyrax to maintain body temperatures with very little thermoregulatory cost. Differences were also recorded in behavioural patterns in rock hyrax of different sizes. Juveniles, due to their small body size and high energetic demands foraged more frequently than adult rock hyrax. During summer, rock hyrax spent considerable time in the rock crevices. This was because ambient temperatures exceeded the upper limit of the thermoneutral zone of the rock hyrax throughout most of the day. Rock hyrax therefore escaped the excessive temperatures by utilizing the cooler rock crevices, which remained at temperatures within the rock hyraxes thermoneutral zone. The most frequent behaviour recorded in rock hyrax aboveground was foraging. Since forage was abundant around the rock crevices during summer, predation risk was less of a factor influencing foraging behaviour. Since basking is an essential component of the rock hyraxes thermal biology during winter we examined basking behaviour in more detail. Basking in the morning was not used to increase body temperatures from hypothermic levels as otherwise thought. Instead, it was used to maintain body temperatures at low ambient temperatures by altering posture, orientation to the sun and basking bout lengths. During the early morning, when heating rates were greatest, rock hyrax orientated their bodies exposing the greatest surface area to solar radiation. During midday, reduced basking bout lengths and the reduction of surface areas exposed to the sun reduced the heat loads during the hottest parts of the day. Rock hyrax appeared to utilize the warm rock surfaces during the late afternoon when the sun was setting to maintain body temperatures before entering the crevices for the night. The combination of physiological and behavioural thermoregulation therefore enables rock hyrax to maintain homeostasis with very little energetic costs in an environment that displays variability in both ambient temperatures and resource availability. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2003.

The chief objective of the study was to investigate the population dynamics of the hyrax in the Mountain Zebra National Park (MZNP). To realise this objective information on growth, age determination, reproduction, habitat utilization, behaviour, parasites and mortality had to be gathered. The growth of hyrax in relation to age is described by means of Stevens asymptotic regression equations. Near asymptotic measurements are attained first in hind foot length (at 30-33 months of age), head/body length (at 37-39 months of age), girth (at 41-48 months of age) and body mass (at 68-70 months of age). Allometric growth of the various body measurements was investigated and useful predictive relationships for mass are presented. Age determination of hyrax was studied in detail. Cementum annuli counts provided reliable estimates of age. One primary cementum line is formed annually. The dried eye lens mass was an accurate means of age determination up to c. 72 months of age. A summary of findings which will facilitate age determination of dead animals or skulls, and live animals, is provided. Reproduction in the hyrax was studied with emphasis on breeding season, age-specific litter sizes, prenatal mortality and lactation. Male hyrax attained puberty at 15-17 months of age or one year later. Females generally attained puberty at 15-17 months of age. One female (1,4% of total shot sample for the specific age group) attained puberty at 4-5 months of age. Middle-aged hyrax had significantly larger litter sizes than younger animals. Hyrax in the MZNP feed on at least 80 different plant species belonging to 33 plant families. Crude protein of stomach contents and faecal samples showed little seasonal fluctuation implying that hyrax in the MZNP were on a stable quality diet. Female hyrax enjoyed a significantly better quality diet than males for the four month period prior to parturition and during the first two months of lactation. The crude protein values of faecal and stomach samples had a significant correlation. Body fat of male and female hyrax showed seasonal variation related to physiologically stressful periods. Seasonal differences in activity patterns were demonstrated. The basic structure of hyrax social organization is the multi-female kinship group that is matrilocal. Territorial dominant males maintain harems and exclude all other adult males. Peripheral males occupy areas on the periphery of the activity areas of other members of the hyrax colony. Peripheral males do not form bachelor groups and are normally younger than territorial males. It is suggested that territorial males are able to monopolize between 3-17 females in a successful and energetic manner. Both natal and breeding dispersal occurred, the former being considerably more extensive than the latter. The ecto- and endoparasites of hyrax were identified and their burdens quantified over a 13 month period. Juveniles had significantly larger burdens of ectoparasites than did adults. Information on age-specific mortality was obtained from skulls collected in the field and at black eagles' nests. Losses that occurred in the study population due to caracal and black eagle predation were quantified. Evidence is supplied which indicates that juvenile mortality may fluctuate markedly. The population dynamics of the hyrax population in the MZNP was studied by the use of time specific life-tables, models on population growth rates, population simulation models and sensitivity analysis. Sensitivity coefficients were used as a predictor of population regulation. Female juvenile mortality was considered to be the main regulating factor. Changes in fecundity schedule are important compensatory mechanisms and also play an important role in the regulation of a hyrax population. Predation, particularly by caracal, is thought to dampen population fluctuations.

Ph.D., Faculty of Science, University of the Witwatersrand, 2011 / The rock hyrax, Procavia capensis, is a social diurnal mammal that typically lives in colonies on rocky outcrops and is found throughout most parts of Southern Africa. The aim of this thesis was to describe the sleep phenomenology of the rock hyrax. By means of immunohistochemistry the location and distribution of the cholinergic, catecholaminergic, serotonergic, orexinergic, histaminergic, and the GABAergic systems were described. For the most part these systems and their terminal network distributions followed the general mammalian organisational plan; however, several features, potentially unique to the rock hyrax, were found. These include the presence of cholinergic neurons in the AD and AV nuclei of the dorsal thalamus, parvo- and magnocellular divisions of the cholinergic LDT and PPT nuclei. A dense orexinergic terminal network distribution was noted in the regions coincident with the AD nucleus, a feature only observed in other diurnal mammals. Parvalbumin neurons did not show any association to the sleep related nuclei, whereas calbindin and calretinin neurons were found in all sleep related areas, though with differing densities and some homogeneities. The physiological measurable parameters of sleep were recorded continuously for 72 h under both solitary and social conditions and compared to determine whether differences existed. The results revealed that no major differences existed between the social and solitary conditions, but sleep intensity and REM duration (particularly REM0) was more pronounced in the social condition. REM was ambiguous in these animals, and led to its subdivision into REM1 and REM0. It is possible that REM1 could be a form of low voltage slow wave sleep, but further investigation is required. If REM1 is a form of NonREM sleep it would imply that the rock hyrax has the lowest amount of REM sleep of any terrestrial mammal studied to date.

Please read the abstract in the section 00front of this document. Please note that pages 9 and 10 are missing from the available paper, as well as the microfiche copy. / Thesis (PhD (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

Cette thèse présente les données des pollens et micro-charbons fossiles couvrant la période des 50 000 dernières années à partir de sites sélectionnés transversalement nord-sud du désert de Namib. Dans le cadre de cette thèse, on utilise le rock hyrax middens, l’accumulation des boulettes et des urines fossilisés du Procavia capensis, représentant une excellente archive pour archives pour la préservation des pollens et micro-charbons à long-terme. Trois sites des hyrax middens ont été sélectionnés pour l'analyse: au sud du désert de Namib (Pella), la marge est des dunes de sable de Namib (Zizou) et le centre de la Namib (Spitzkoppe). En plus, le régime pluvial de ces sites se caractérise par une forte variabilité annuelle et interannuelle. En conséquence, tous ces sites se situent au long de l’écotone du Désert et du biome Nama-Karoo, ainsi qu'à l’est (biome de Savane). Alors que ces sites sont répertoriés dans des écosystèmes similaires, l’écotone, lui, est considéré comme une zone potentiellement très sensible au changement du système climatique régional. Un intérêt spécifique de ces enregistrements terrestres est pour évaluer s’ils corroborent ou s’opposent avec les résultats provenant ceux des sédiments marins de la côte namibienne, en particulier la conclusion : l’abondance des taxa dominants du Fynbos Biome du Cape peut indiquer significativement une expansion vers le nord de la flore du Cape pendant les périodes plus froides glaciaires. Selon les sites d’études sélectionnées, les conclusions principales de ce travail sont les suivantes:Les hyrax middens de Pella fournissent le premier enregistrement pollinique continué au sud du désert de Namib durant la période des 50 000 dernières années. Ces données polliniques ont permis de reconstruire le changement de la végétation et d'estimer la température et l'aridité. Les résultats indiquent que la période glaciaire se caractérise par une augmentation de la disponibilité de l'eau sur le site par rapport à l'Holocène. Les changements de la température et de l'évapotranspiration potentielle semblent avoir joué un rôle important dans la détermination de l'équilibre hydrologique.L'enregistrement de Zizou hyrax midden met en évidence des changements de la végétation à la marge l'est des dunes de sable depuis 38 000 ans cal BP. La végétation de la période glaciaire se caractérise par les pourcentages relativement élevés des Astéracées pollen, et plus particulièrement par des taxa du climat plus froid: Stoebe et Artemisia¬-type. En accord avec les données de Pella, le réchauffement au début de l'Holocène indiqué par la dominance de pollen des graminées dans l'assemblage pollinique suggère une expansion du biome de Désert.Les hyrax middens de Spitzkoppe enregistrent les changements de la végétation dans le centre du désert de Namib au cours des 32 000 dernières années. Les résultats sont globalement cohérents en comparant aux autres enregistrements terrestres dans la région. L'analyse de ces données n'est cependant pas encore terminée.Dans tous ces sites, une variabilité significative a été observée à la fois dans la dernière période glaciaire et l'Holocène. Les conditions plus froides de l'ère glaciaire semblent être caractérisées par une augmentation de la disponibilité de l'eau le long de la totalité de notre zone d'étude. Au contraire des résultats provenant des carottes marines, nos enregistrements indiquent aucune expansion de la végétation de Fynbos biome, et seulement des traces de Restionaceae pollen dans le site extrêmement au sud à Pella (pas plus de 1%), mais aucun trace de ce pollen n'ayant été observé à Zizou ainsi qu’à Spitzkoppe. / This thesis presents fossil pollen and microcharcoal data during the last 50,000 years from a north-south transect of the Namib Desert. The arid environment of the Namib precludes the development of permanent wetlands, and as a result few palaeoenvironmental records exist from the region. In this study, we employ rock hyrax middens – fossilised accumulations of the faecal pellets and urine of the Procavia capensis. Hyrax middens from three sites were selected for analysis: the southern Namib (Pella), the eastern margin of Namib Sand Sea (Zizou), and the central Namib (Spitzkoppe). The results from these terrestrial sites are the extent to which they may corroborate or conflict with findings from pollen records obtained from marine sediments of the Namibian coast.The Pella hyrax middens provide the first continuous pollen record from the southern Namib Desert since the last 50,000 years, and are used to reconstruct vegetation change and quantitative estimates of temperature and aridity. Results indicate that the last glacial period was characterised by increased water availability relative to the Holocene. Changes in temperature and potential evapotranspiration appear to have played a significant role in determining the hydrologic balance. The record can be considered in two sections: 1) the last glacial period, when low temperatures favoured the development of more mesic Nama-Karoo vegetation at the site, with periods of increased humidity concurrent with increased coastal upwelling, both responding to lower global/regional temperatures; and 2) the Holocene, high temperatures and potential evapotranspiration resulted in increased aridity and an expansion of the Desert Biome.Considered in the context of discussions of forcing mechanisms of regional climate change and environmental dynamics, the results from Pella stand in clear contrast with many inferences of terrestrial environmental change derived from regional marine records. Observations of a strong precessional signal and interpretations of increased humidity during phases of high local summer insolation in the marine records are not consistent with the data from Pella. Similarly, while high percentages of Restionaceae pollen has been observed in marine sediments during the last glacial period, they do not exceed 1% of the assemblage from Pella, indicating that no significant expansion of the Fynbos Biome has occurred during the last 50,000 years.The Zizou hyrax midden highlights vegetation changes on the eastern margin of the Namib Sand Sea since 38,000 cal BP. Results show the different vegetation compositions between the last glacial period and the Holocene. Glacial vegetation characterised with relatively high percentages of Asteraceae pollen, particularly cool climate taxa such as Stoebe and Artemisia types. Similar to the data from Pella, with the onset of Holocene warming grass pollen comes to dominate the assemblage, suggesting an expansion of the Desert Biome. We suggest that the climate during the last glacial period was more humid, and supported the development of shrubs/small trees. Arid conditions during the Holocene saw the depletion of this resource, and the development of grasslands that could exploit the rare rains that the region experiences today. In common with the Pella record, no elements of the Cape flora are found in the Zizou middens.The Spitzkoppe hyrax middens record vegetation changes in the central Namib during the last 32,000 years. The last glacial vegetation compositions composed of Olea, Artemisia¬-type, Stoebe¬-type and grasses. In the Holocene, the arboreal taxa such as Olea was replaced by others like Eculea, Dombeya, Commiphora, and Croton¬-type with relative higher percentage of grasses at early Holocene.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19221号 / 理博第4113号 / 新制||理||1592(附属図書館) / 32220 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 伊谷 原一, 教授 幸島 司郎, 教授 村山 美穂 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-11-13T11:21:21Z No. of bitstreams: 1 ANDRE_XAVIER_PADILHA_FAVORETO_DIS.pdf: 4813223 bytes, checksum: 0ef272778a4eecc19798203feb8449ef (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-11-13T16:37:50Z (GMT) No. of bitstreams: 1 ANDRE_XAVIER_PADILHA_FAVORETO_DIS.pdf: 4813223 bytes, checksum: 0ef272778a4eecc19798203feb8449ef (MD5) / Made available in DSpace on 2018-11-13T17:02:11Z (GMT). No. of bitstreams: 1 ANDRE_XAVIER_PADILHA_FAVORETO_DIS.pdf: 4813223 bytes, checksum: 0ef272778a4eecc19798203feb8449ef (MD5) Previous issue date: 2018-03-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This retrospective study aims to evaluate the morphological changes produced after and surgically assisted maxillary rapid expansion (ERMAC). A three-dimensional evaluation was performed with CBT and scanning of the intraoral and gingival models at the preoperative (T0) and postoperative (T1 and T2) moments in order to evaluate linear and angular movements with bone and dental changes underlying. The possible morphological alterations of the related structures were evaluated: nasopharynx volume, oropharynx volume in relation to ERMAC. The sample consisted of 15 individuals (8 males and 7 females aged 19 to 54 years) submitted to MRS. In general, ERMAC produced a significant increase in all linear distances of the maxilla. There was a greater expansion of the maxilla in the anterior region than in the posterior one. The ERMAC produced a significant increase of the skeletal dimensions of the maxilla in the transversal direction. In the airways, there was a significant increase in all patients and the greatest effects of ERMAC occurred at the dental level, with the buccal inclination of the first molars and the upper premolars being observed. / Objetiva-se com este estudo retrospectivo avaliar as altera??es morfol?gicas produzidas ap?s e expans?o r?pida maxilar assistida cirurgicamente (ERMAC). Realizou-se uma avalia??o tridimensional com TCCB e escaneamento dos modelos de gesso e dos dentes intraoral no momento pr?-operat?rio (T0) e p?s-operat?rio (T1 e T2) a fim de avaliar os movimentos lineares e angulares com as altera??es ?sseas e dent?rias subjacentes. Avaliou - se as poss?veis altera??es morfol?gicas das estruturas correlatas: volume da nasofaringe, volume da orofaringe com rela??o a ERMAC. A amostra constituiu-se de 15 indiv?duos (8 homens e 7 mulheres com idades entre 19 e 54 anos) submetidos a ERMAC. De modo geral, a ERMAC produziu aumento significativo de todas as dist?ncias lineares da maxila. Houve maior expans?o da maxila na regi?o anterior do que na posterior. A ERMAC produziu aumento significativo das dimens?es esquel?ticas da maxila no sentido transversal. Nas vias a?reas houve aumento significativo em todos os pacientes e os maiores efeitos da ERMAC ocorreram no n?vel dent?rio, sendo observada a inclina??o vestibular dos primeiros molares e nos pr?-molares superiores.