School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Johannesburg, Republic of South Africa.
Department of Zoology, KSU Mammals Research Chair, College of Science, King Saud University, Riyadh, Saudi Arabia.
Sleep. 2018 May 1;41(5). doi: 10.1093/sleep/zsy038.
The Arabian oryx lives under hyperarid conditions in the Arabian Desert and exhibits temporal niche switching of activity patterns at a seasonal level. The objective of the current study was to provide a polysomnographic-based study of sleep in free-roaming Arabian oryx in their natural habitat to determine whether extreme seasonal climate variations resulted in changes in sleep patterns and physiology associated with the seasonal switching of temporal niches.
Electroencephalography, nuchal electromyography, actigraphy, and subcutaneous temperature were recorded in free-roaming Arabian oryx in the Mahazat as-Sayd Protected Area, Kingdom of Saudi Arabia during winter and summer.
Total daily sleep time in winter was 6.69 and 3.77 hr in summer. In winter, oryx exhibited nocturnal sleep typical of artiodactyls of around 60 kg body mass. In summer, oryx slept mostly during the day and subcutaneous temperature was seen to rise during sleep, but not as rapidly as the rises observed in ambient air temperature. Rapid eye movement sleep formed a very small percentage of total sleep time, especially so in the summer.
The unusual sleep patterns and physiology during summer appear to be related to high ambient air temperatures that affect both intrinsic and extrinsic factors necessary for survival. The Arabian oryx appears to use sleep physiology as an adaptive thermoregulatory mechanism in the hot summer months.
阿拉伯大羚羊生活在阿拉伯沙漠的极度干旱环境中，在季节性水平上表现出活动模式的时间生态位转换。本研究的目的是对自由放养的阿拉伯大羚羊在其自然栖息地的睡眠进行多导睡眠描记术研究，以确定极端季节性气候变化是否导致与时间生态位季节性转换相关的睡眠模式和生理学变化。
在沙特阿拉伯的 Mahazat as-Sayd 保护区，对自由放养的阿拉伯大羚羊进行脑电图、颈肌肌电图、活动记录仪和皮下温度记录，分别在冬季和夏季进行。
冬季的总日睡眠时间为 6.69 小时，夏季为 3.77 小时。冬季，大羚羊表现出典型的偶蹄类 60 公斤体重左右的夜间睡眠。在夏季，大羚羊主要在白天睡觉，并且在睡眠期间观察到皮下温度升高，但不如环境空气温度升高得那么快。快速眼动睡眠在总睡眠时间中所占比例非常小，尤其是在夏季。
夏季不寻常的睡眠模式和生理学似乎与影响生存所必需的内在和外在因素的高环境空气温度有关。阿拉伯大羚羊似乎在炎热的夏季月份将睡眠生理学用作一种适应性体温调节机制。
