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Paul R. Manger - One of the best experts on this subject based on the ideXlab platform.
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nuclear organization of the rock hyrax Procavia capensis amygdaloid complex
Brain Structure & Function, 2016Co-Authors: Audemarie Limacherburrell, Nadine Gravett, Busisiwe C Maseko, Adhil Bhagwandin, Paul R. MangerAbstract:The current study details the nuclear organization of the rock hyrax amygdaloid complex using both Nissl and myelin stains, along with a range of immunohistochemical stains. The rock hyrax appears to be the least derived of the Afrotherians, a group with a huge range of body phenotypes, life histories and specialized behaviours, brain sizes, and ecological niches. In this sense, the rock hyrax represents a species where the organization of the amygdaloid complex may be reflective of that in stem Eutherian mammals. Our analysis indicates that the nuclear organization of the rock hyrax amygdaloid complex is indeed very similar to that in other mammals studied, with four major nuclear groupings (the deep or basolateral group; the superficial or cortical-like or corticomedial group; the centromedial group; and the other amygdaloid nuclei) being observed, which is typical of Eutherian mammals. Moreover, each of these groupings is composed of several nuclei, the vast majority of which were readily identified in the rock hyrax. Small nuclei identified in rodents and primates were absent in the superficial and centromedial groups, seemingly involved with olfaction. A novel shell-like nucleus of the accessory basal nuclear cluster was observed in the rock hyrax, again, likely to be involved in olfaction. The current study underlines the conserved nature of nuclear parcellation in the Eutherian mammal amygdaloid complex and indicates that across most species, the flow of information processing related to species-specific affective-laden stimuli and the resultant physiological and behavioural outcomes are likely to be similar across species.
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sleep in the rock hyrax Procavia capensis
Brain Behavior and Evolution, 2012Co-Authors: Nadine Gravett, Oleg I Lyamin, Adhil Bhagwandin, Jerome M Siegel, Paul R. MangerAbstract:We investigated sleep in therock hyrax, Procavia capensis, a social mammal that typically lives in colonies on rocky outcrops throughout most parts of Southern Africa. The sleep of 5 wild-captured, adult rock hyraxes was recorded continuously for 72 h using telemetric relay of signals and allowing unimpeded movement. In addition to waking, slow wave sleep (SWS) and an unambiguous rapid eye movement (REM) state, a sleep state termed somnus innominatus (SI), characterized by low-voltage, high-frequency electroencephalogram, an electromyogram that stayed at the same amplitude as the preceding SWS episode and a mostly regular heart rate, were identified. If SI can be considered a form of low-voltage non-REM, the implication would be that the rock hyrax exhibits the lowest amount of REM recorded for any terrestrial mammal studied to date. Conversely, if SI is a form of REM sleep, it would lead to the classification of a novel subdivision of this state; however, further investigation would be required. The hyraxes spent on average 15.89 h (66.2%) of the time awake, 6.02 h (25.1%) in SWS, 43 min (3%) in SI and 6 min (0.4%) in REM. The unambiguous REM sleep amounts were on average less than 6 min/day. The most common state transition pathway in these animals was found to be wake → SWS → wake. No significant differences were noted with regard to total sleep time, number of episodes and episode duration for all states between the light and dark periods.Thus, prior classification of the rock hyrax as strongly diurnal does not appear to hold under controlled laboratory conditions.
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Sleep in the Rock Hyrax, Procavia capensis
Brain Behavior and Evolution, 2012Co-Authors: Nadine Gravett, Oleg I Lyamin, Adhil Bhagwandin, Jerome M Siegel, Paul R. MangerAbstract:We investigated sleep in therock hyrax, Procavia capensis , a social mammal that typically lives in colonies on rocky outcrops throughout most parts of Southern Africa. The sleep of
Christopher S. Henshilwood - One of the best experts on this subject based on the ideXlab platform.
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Rock Hyraxes ( Procavia capensis ) from Middle Stone Age Levels at Blombos Cave, South Africa
African Archaeological Review, 2014Co-Authors: Shaw Badenhorst, Karen L. Van Niekerk, Christopher S. HenshilwoodAbstract:The ∼100 ka Middle Stone Age levels at Blombos Cave, southern Cape, South Africa, contain numerous rock hyrax (Procavia capensis) remains. It is often ambiguous to interpret rock hyrax remains from archaeological deposits deriving from cave and shelter sites in southern Africa as the agent or agents of accumulation may be difficult to establish. In this paper, the different taphonomic signatures separating anthropogenic from natural accumulations at Blombos Cave are considered. The analysis indicates that although a few specimens show evidence for raptor and carnivore accumulation, there is also substantial evidence that suggests humans preyed on these small mammals during different times of the year.
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Rock Hyraxes (Procavia capensis) from Middle Stone Age Levels at Blombos Cave, South Africa
African Archaeological Review, 2014Co-Authors: Shaw Badenhorst, Karen L. Van Niekerk, Christopher S. HenshilwoodAbstract:The ∼100 ka Middle Stone Age levels at Blombos Cave, southern Cape, South Africa, contain numerous rock hyrax ( Procavia capensis ) remains. It is often ambiguous to interpret rock hyrax remains from archaeological deposits deriving from cave and shelter sites in southern Africa as the agent or agents of accumulation may be difficult to establish. In this paper, the different taphonomic signatures separating anthropogenic from natural accumulations at Blombos Cave are considered. The analysis indicates that although a few specimens show evidence for raptor and carnivore accumulation, there is also substantial evidence that suggests humans preyed on these small mammals during different times of the year. Dans la grotte de Blombos (Cap-Occidental, Afrique du Sud), les niveaux Middle Stone Age datés d’environ 100 ka se caractérisent notamment par l’abondance des restes de Daman du Cap (Procavia capensis). L’interprétation de l’abondance du Daman dans les sites archéologiques sud-africains est souvent problématique, car il est particulièrement difficile en contexte de grotte ou d’abri de déterminer le ou les agent(s) responsable(s) de l’accumulation de ses restes. Dans cette contribution, les différentes signatures taphonomiques utilisables pour distinguer accumulations naturelles et anthropiques sont considérées. Nos analyses indiquent que, même si quelques restes présentent des traces évidentes d’action par un rapace ou un carnivore, de nombreux arguments suggèrent que ce petit mammifère représentait une proie de choix pour les groupes humains, et ce à différentes périodes de l’année.
W. Van Hoven - One of the best experts on this subject based on the ideXlab platform.
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Volatile fatty acid production in the hindgut of Procavia capensis
Comparative Biochemistry and Physiology Part A: Physiology, 2003Co-Authors: Anette K. Eloff, W. Van HovenAbstract:Abstract 1. 1. Two sites of fermentation have developed in the hindgut of hyrax. 2. 2. The sacculation has a larger digesta mass and volatile fatty acid production rate than the caeca. 3. 3. Mean molar percentage of acids amounted to 63.9% acetic acid, 22.9% propionic acid and 6.0% butyric acid for the sac and caeca. 4. 4. Total volatile fatty acid production per day did not differ significantly among seasons, and energy available from the volatile fatty acids averaged 69.9% of the basal metabolic requirements and 33.8% of the average daily metabolic requirements.
Nicolaas Gey C Van Pittius - One of the best experts on this subject based on the ideXlab platform.
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pulmonary infection due to the dassie bacillus mycobacterium tuberculosis complex sp in a free living dassie rock hyrax Procavia capensis from south africa
Tuberculosis, 2008Co-Authors: Sven D C Parsons, Quinton E Martins, Elizabeth M. Streicher, Tertius A. Gous, Paul D. Van Helden, Robin M Warren, William G.c. Horsnell, Sarah Smith, Nicolaas Gey C Van PittiusAbstract:Summary We report a case of extensive necrogranulomatous pneumonia due to infection with the dassie bacillus ( Mycobacterium tuberculosis complex sp.) in a free-living pregnant adult female dassie (rock hyrax— Procavia capensis ). A juvenile female dassie from the same colony also showed a focal lesion in the lungs suggestive of mycobacterial pneumonia. Our findings indicate the widespread occurrence of the dassie bacillus in free-living dassies and suggest very high infection rates in some populations. The introduction of South African dassies into novel environments should be considered in this light.
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Pulmonary infection due to the dassie bacillus (Mycobacterium tuberculosis complex sp.) in a free-living dassie (rock hyrax—Procavia capensis) from South Africa
Tuberculosis, 2007Co-Authors: Sven D C Parsons, Quinton E Martins, Elizabeth M. Streicher, Sarah G.d. Smith, Tertius A. Gous, Paul D. Van Helden, Robin M Warren, William G.c. Horsnell, Nicolaas Gey C Van PittiusAbstract:Summary We report a case of extensive necrogranulomatous pneumonia due to infection with the dassie bacillus ( Mycobacterium tuberculosis complex sp.) in a free-living pregnant adult female dassie (rock hyrax— Procavia capensis ). A juvenile female dassie from the same colony also showed a focal lesion in the lungs suggestive of mycobacterial pneumonia. Our findings indicate the widespread occurrence of the dassie bacillus in free-living dassies and suggest very high infection rates in some populations. The introduction of South African dassies into novel environments should be considered in this light.
Nadine Gravett - One of the best experts on this subject based on the ideXlab platform.
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nuclear organization of the rock hyrax Procavia capensis amygdaloid complex
Brain Structure & Function, 2016Co-Authors: Audemarie Limacherburrell, Nadine Gravett, Busisiwe C Maseko, Adhil Bhagwandin, Paul R. MangerAbstract:The current study details the nuclear organization of the rock hyrax amygdaloid complex using both Nissl and myelin stains, along with a range of immunohistochemical stains. The rock hyrax appears to be the least derived of the Afrotherians, a group with a huge range of body phenotypes, life histories and specialized behaviours, brain sizes, and ecological niches. In this sense, the rock hyrax represents a species where the organization of the amygdaloid complex may be reflective of that in stem Eutherian mammals. Our analysis indicates that the nuclear organization of the rock hyrax amygdaloid complex is indeed very similar to that in other mammals studied, with four major nuclear groupings (the deep or basolateral group; the superficial or cortical-like or corticomedial group; the centromedial group; and the other amygdaloid nuclei) being observed, which is typical of Eutherian mammals. Moreover, each of these groupings is composed of several nuclei, the vast majority of which were readily identified in the rock hyrax. Small nuclei identified in rodents and primates were absent in the superficial and centromedial groups, seemingly involved with olfaction. A novel shell-like nucleus of the accessory basal nuclear cluster was observed in the rock hyrax, again, likely to be involved in olfaction. The current study underlines the conserved nature of nuclear parcellation in the Eutherian mammal amygdaloid complex and indicates that across most species, the flow of information processing related to species-specific affective-laden stimuli and the resultant physiological and behavioural outcomes are likely to be similar across species.
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sleep in the rock hyrax Procavia capensis
Brain Behavior and Evolution, 2012Co-Authors: Nadine Gravett, Oleg I Lyamin, Adhil Bhagwandin, Jerome M Siegel, Paul R. MangerAbstract:We investigated sleep in therock hyrax, Procavia capensis, a social mammal that typically lives in colonies on rocky outcrops throughout most parts of Southern Africa. The sleep of 5 wild-captured, adult rock hyraxes was recorded continuously for 72 h using telemetric relay of signals and allowing unimpeded movement. In addition to waking, slow wave sleep (SWS) and an unambiguous rapid eye movement (REM) state, a sleep state termed somnus innominatus (SI), characterized by low-voltage, high-frequency electroencephalogram, an electromyogram that stayed at the same amplitude as the preceding SWS episode and a mostly regular heart rate, were identified. If SI can be considered a form of low-voltage non-REM, the implication would be that the rock hyrax exhibits the lowest amount of REM recorded for any terrestrial mammal studied to date. Conversely, if SI is a form of REM sleep, it would lead to the classification of a novel subdivision of this state; however, further investigation would be required. The hyraxes spent on average 15.89 h (66.2%) of the time awake, 6.02 h (25.1%) in SWS, 43 min (3%) in SI and 6 min (0.4%) in REM. The unambiguous REM sleep amounts were on average less than 6 min/day. The most common state transition pathway in these animals was found to be wake → SWS → wake. No significant differences were noted with regard to total sleep time, number of episodes and episode duration for all states between the light and dark periods.Thus, prior classification of the rock hyrax as strongly diurnal does not appear to hold under controlled laboratory conditions.
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Sleep in the Rock Hyrax, Procavia capensis
Brain Behavior and Evolution, 2012Co-Authors: Nadine Gravett, Oleg I Lyamin, Adhil Bhagwandin, Jerome M Siegel, Paul R. MangerAbstract:We investigated sleep in therock hyrax, Procavia capensis , a social mammal that typically lives in colonies on rocky outcrops throughout most parts of Southern Africa. The sleep of
