Department of Ecology, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, China.
Am J Primatol. 2019 Sep;81(9):e23049. doi: 10.1002/ajp.23049. Epub 2019 Sep 9.
Considering the high energetic costs of maintaining constant body temperature, mammals must adjust their thermoregulatory behaviors in response to cold temperatures. Although primate daytime thermoregulation is relatively well studied, there is limited research in relation to nighttime strategies. To investigate how Skywalker hoolock gibbons (Hoolock tianxing) cope with the low temperatures found in montane forests, we collected sleep-related behavior data from one group (NA) and a single female (NB) at Nankang (characterized by extensive tsaoko plantations) between July 2010 and September 2011, and one group (BB) at Banchang (relatively well-managed reserve forest) between May 2013 and May 2015 in Mt. Gaoligong, Yunnan, China. The annual mean temperature was 13.3°C at Nankang (October 2010 to September 2011) and 13.0°C at Banchang (June 2013 to May 2015) with temperatures dropping below -2.0°C at both sites, making them the coldest known gibbon habitats. The lowest temperatures at both sites remained below 5.0°C from November to March, which we, therefore, defined as the "cold season". The hoolock gibbons remained in their sleeping trees for longer periods during the cold season compared to the warm season. Sleeping trees found at lower elevations and closer to potential feeding trees were favored during cold seasons at both sites. In addition, the gibbons were more likely to huddle together during cold seasons. Our results suggest that cold temperatures have a significant effect on the sleeping behavior of the Skywalker hoolock gibbon, highlighting the adaptability of this threatened species in response to cold climates.
考虑到维持体温恒定的高能耗，哺乳动物必须根据低温环境调整其体温调节行为。尽管灵长类动物的日间体温调节已得到较为充分的研究，但夜间策略的相关研究仍很有限。为了研究天行长臂猿（Hoolock tianxing）如何应对山地森林中的低温，我们于 2010 年 7 月至 2011 年 9 月期间在南康（广泛种植铁皮石斛）收集了一组（NA）和一只雌性（NB）的睡眠相关行为数据，于 2013 年 5 月至 2015 年 5 月在高黎贡山的板厂（管理较好的保护区森林）收集了一组（BB）的睡眠相关行为数据。南康的年平均气温为 13.3°C（2010 年 10 月至 2011 年 9 月），板厂的年平均气温为 13.0°C（2013 年 6 月至 2015 年 5 月），两地的温度均曾降至-2.0°C 以下，使它们成为已知最寒冷的长臂猿栖息地。两地的最低温度在 11 月至 3 月期间均保持在 5.0°C 以下，我们因此将这段时期定义为“寒冷季节”。与温暖季节相比，寒冷季节中天行长臂猿留在睡眠树上的时间更长。在两个地点的寒冷季节中，较低海拔和靠近潜在觅食树的睡眠树更受青睐。此外，寒冷季节中天行长臂猿更倾向于挤在一起。我们的研究结果表明，低温对天行长臂猿的睡眠行为有显著影响，突显了该濒危物种对寒冷气候的适应能力。
