Sleep in the Arabian oryx, Oryx leucoryx

Original published work submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Doctor of Philosophy, Johannesburg, 2018The evolution and function of sleep remains an enigma in modern science. Significant variation can be observed within species and across taxa. Little is understood about how sleep exists, or presents itself in species surviving in extreme conditions. For example, harsh desert ecosystems with notably lower survival rates for resident species. It has been hypothesized that specialized sleep-related behaviours impact thermoregulation to promote survival advantage. The threatened Arabian oryx (Oryx leucoryx), a member of the Cetartiodactyl superorder, is a large desert dwelling ungulate species successfully residing in the arid zones of the Middle East. Arabian Oryx exhibit numerous morphophysiological adaptations and capabilities to cope with their harsh environment. The current thesis provides an examination of the neuroanatomy, physiology and behavioural patterns related to sleep in wild, freeroaming Arabian oryx under natural conditions. It was our objective to determine whether the extreme conditions and climate of the Arabian Desert has led to novelties within the organization of the oryx’s sleep related neuronal architecture, seasonal behaviour patterns and sleep physiology. Using immunohistochemistry and stereology our results indicate the sleep related nuclei in the brain of the oryx exhibit a typical mammalian organizational plan with additional order-specific and novel, species-specific features. Actigraphy revealed that oryx exhibit temporal niche switching patterns seasonally presenting with winter diurnal- and summer nocturnal activity and intermittent patterns during the transitional periods of spring and autumn. Polysomnography results indicate novel sleep patterns between seasons and physiologically confirm activity-based temporal niche switching at a seasonal level. Our work covers the first examination of the Arabian oryx brain sleep centers as well as its yearlong activity patterns. Importantly, it is the first examination of physiological sleep in wild mammals within a desert environment. Our results suggest that ambient temperature acts a dominant driving force for the adaptive behavioural and physiological features described. The Arabian oryx is a remarkable species, well adapted to such an extreme environment and its highly plastic survival mechanisms appear unique. Considering the continual desertification of our planet and the predicted consequences of climate change, knowledge of such species and their continued conservation is of vital importanceXL201

Topography and Composition of the Iliolumbar Veins in a South African Cohort: Implications for Spinal Surgery

Study Design A descriptive cross-sectional study of the anatomical variations, morphometry, and histology of the iliolumbar veins (ILVs). Purpose This study aimed to describe the anatomical variations of the ILVs and determine their tissue composition in South African cadavers of European descent. Overview of Literature A safe anterior surgical approach to the L4/L5 intervertebral disc space requires understanding the anatomy of the ILVs. Limited understanding of ILVs and their variations may lead to inadvertent avulsion of veins with subsequent hemorrhage and damage to the adjacent nerves intraoperatively. Variations in ILVs are population specific, but such reports are limited in the South African population. Methods Eighty-nine adult cadavers were dissected to reveal ILV patterns. The variations (origin, course, and drainage pattern), morphometries, and topography of the ILVs were studied. A total of 19 (10 proximal, nine distal) ILVs were processed for hematoxylin and eosin, Masson’s trichrome, and Verhoeff’s histological staining to determine the tissue composition. Results The ILVs were identified in 100% of the cases, and 45% of the ILVs were anastomosed to each other bilaterally. The right-side ILVs terminated into the posterior surfaces of the iliac vessels (p=0.001), whereas the left-side ILVs terminated into the lateral surfaces (p=0.001). The left-side proximal ILVs had higher elastic fiber composition (p=0.030). The ratio of the ILVs’ elastic fibers to collagen fibers was 1:9, and 61% of the cadavers exhibited type 1 ILV pattern. Moreover, 42% of the ILVs were at the S1 vertebral level with 31% lying between L4 and L5 spinal nerve roots. The obturator nerve coursed anteriorly to the ILVs in 96% of cases. Conclusions The ILV variations described for South Africans present new additional patterns, such as bilateral anastomosis and laterality of the terminal drainage. The ILVs have more collagen fibers than elastic fibers, predisposing them to avulsion during surgical retraction. The identification of all the ILVs is crucial to minimize inadvertent hemorrhage and damage to adjacent structures

Arabian oryx (Oryx leucoryx) respond to increased ambient temperatures with a seasonal shift in the timing of their daily inactivity patterns

The Arabian oryx inhabits an environment where summer ambient temperatures can exceed 40 °C for extended periods of time. While the oryx uses a suite of adaptations that aid survival, the effects of this extreme environment on inactivity are unknown. To determine how the oryx manages inactivity seasonally, we measured the daily rhythm of body temperature and used fine-grain actigraphy, in 10 animals, to reveal when the animals were inactive in relation to ambient temperature and photoperiod. We demonstrate that during the cooler winter months, the oryx was inactive during the cooler parts of the 24-h day (predawn hours), showing a nighttime (nocturnal) inactivity pattern. In contrast, in the warmer summer months, the oryx displayed a bimodal inactivity pattern, with major inactivity bouts (those greater than 1 h) occurring equally during both the coolest part of the night (predawn hours) and the warmest part of the day (afternoon hours). Of note, the timing of the daily rhythm of body temperature did not vary seasonally, although the amplitude did change, leading to a seasonal alteration in the phase relationship between inactivity and the body temperature rhythm. Because during periods of inactivity the oryx were presumably asleep for much of the time, we speculate that the daytime shift in inactivity may allow the oryx to take advantage of the thermoregulatory physiology of sleep, which likely occurs when the animal is inactive for more than 1 h, to mitigate environmentally induced increases in body temperature.National Plan for Science, Technology and Innovation (MAARIFAH), King Abdulaziz City for Science and Technology, Kingdom of Saudi Arabia, Award Number 11-ENV1918-02.http://jbr.sagepub.comhb2016Mammal Research Institut

The third head of the biceps brachii muscle exhibiting variable shape presentation: Prevalence, variability and clinical considerations

Introduction: The third head of the biceps brachii is the predominant variation of the arm muscles. Awareness of muscular variations is essential for the management of upper limb pathologies. Variations in the shape of the muscles are rarely explored. This study aimed to describe the prevalence and anatomical presentation of the third head of the biceps brachii muscle (origin, insertion and innervation) with an emphasis on the shape and form variations. Materials and methods: Biceps brachii of eighty-nine cadavers were examined. The presence of the third head, its origin, shape patterns, blood supply, and nerve innervation were determined and recorded. Results: The third head of the biceps brachii was present in 20.2 %, with a prevalence of 22.2 % in males and 18.2 % in females. Half (50 %) of these were bilateral presentations. Most (92 %) of the third head of the biceps brachii variations were flat, thin and straight in shape. All the shape variation patterns were observed in males and on the left arm. The third head originated from the humerus on its anteromedial aspect in 92 % of cases. The musculocutaneous nerve innervated the third head of the biceps brachii in 96 % of the cases, and a nerve anomaly of musculocutaneous and median nerves innervated it in a single (4 %) case. The muscular branches of the brachial artery supplied the third head of the biceps brachii in all cases. Conclusion: Studies on the variation of arm muscles may assist in identifying new patterns of morphological variations like the shape of the muscle and may aid in the accurate diagnosis and management of arm pathologies

Forensic Facial Comparison: Current Status, Limitations, and Future Directions

Global escalation of crime has necessitated the use of digital imagery to aid the identification of perpetrators. Forensic facial comparison (FFC) is increasingly employed, often relying on poor-quality images. In the absence of standardized criteria, especially in terms of video recordings, verification of the methodology is needed. This paper addresses aspects of FFC, discussing relevant terminology, investigating the validity and reliability of the FISWG morphological feature list using a new South African database, and advising on standards for CCTV equipment. Suboptimal conditions, including poor resolution, unfavorable angle of incidence, color, and lighting, affected the accuracy of FFC. Morphological analysis of photographs, standard CCTV, and eye-level CCTV showed improved performance in a strict iteration analysis, but not when using analogue CCTV images. Therefore, both strict and lenient iterations should be conducted, but FFC must be abandoned when a strict iteration performs worse than a lenient one. This threshold ought to be applied to the specific CCTV equipment to determine its utility. Chance-corrected accuracy was the most representative measure of accuracy, as opposed to the commonly used hit rate. While the use of automated systems is increasing, trained human observer-based morphological analysis, using the FISWG feature list and an Analysis, Comparison, Evaluation, and Verification (ACE-V) approach, should be the primary method of facial comparison

Hands of living San resemble those in palaeolithic stencils, not modern Europeans

The hand metrics of Palaeolithic artists show a number of distinctive features that contrast with the low-variance hand metrics of modern Europeans, and with the majority of other modern humans. For example, the D2/D4 ratio in the Palaeolithic artists has a much greater spread of values and a greater degree of sexual dimorphism. We find that living San people, who represent the minority of modern humans that have high-variance genetics, also have a hand metric phenotype like the Palaeolithic artists, different from modern Europeans and other low-variance genetics modern humans. The increased variance and sexual dimorphism of the phenotypic D2/D4 ratio in the San measurements are in keeping with genetic evidence that the San represent one of the oldest human lineages with the greatest genetic diversity. The findings have the implication that the European Palaeolithic cave artists may have been derived from San-like migrants who brought an established artistic tradition from Africa to Europe, only to be replaced as a population, leaving no evidence of their genetics in modern Europeans, as observed for other Palaeolithic genes such as Oase 1

Biological and environmental factors as sources of variation in nocturnal behavior of giraffe

Upon a drastic decline of the giraffe population in the wild, conservation efforts and therefore the role of zoos have become more important than ever. With their unique opportunities, zoos provide excellent conditions to study animal behavior, expanding the knowledge about the giraffe's behavior repertoire and their ability to adapt. This study therefore examined the nocturnal behavior of 63 giraffe living in 13 different EAZA zoos across Germany and the Netherlands. Giraffe were observed and videos recorded via infrared sensitive cameras during the winter seasons 2015–2018. The observation period spanned nightly from 17:00 to 7:00. Thus, 198 nights, with a total of 2772 h were recorded and analyzed. Linear mixed models were then used to assess potential biological and environmental factors influencing behavior during the dark phase. Results show that individual variables such as age, subspecies and motherhood determined nocturnal activity and sleep behavior most. Among the variables studied, husbandry conditions and environmental factors complying with EAZA standards had no influence on the giraffe's nocturnal behavior. By combining nocturnal activity analyses and an assessment of potential influencing factors, our findings present a holistic approach to a better understanding of captive giraffe behavior and allow for management implications