Fuller Andrea, Kamerman Peter R, Maloney Shane K, Matthee André, Mitchell Graham, Mitchell Duncan
School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa.
J Exp Biol. 2005 Aug;208(Pt 15):2855-64. doi: 10.1242/jeb.01714.
We used miniature data loggers implanted in the abdominal cavity to measure core body temperatures at 30 min intervals in eight (three males, five females) adult free-ranging springbok Antidorcas marsupialis in their natural habitat, over a period of 11-13 months. The animals were subjected to a nychthemeral range of air temperature that often exceeded 20 degrees C, with an absolute minimum temperature of -6 degrees C and a maximum of 34 degrees C. Abdominal temperature exhibited a low amplitude (approximately 1.2 degrees C) nychthemeral rhythm, with a temperature peak near sunset and a trough shortly after sunrise. The amplitude of the nychthemeral rhythm of body temperature was not correlated with the 24 h range of air temperature. Although mean 24 h body temperatures were positively correlated with corresponding air temperatures, mean daily body temperature increased, on average, by only 0.02 degrees C per 1 degrees C increase in air temperature, so that it was only approximately 0.3 degrees C higher in summer than in winter. Mean monthly body temperatures were strongly positively correlated with photoperiod and, in parallel with changes in the time of sunrise, the times at which the minimum and maximum body temperatures occurred were shifted approximately 1.2 h earlier in summer than in winter. Annual and daily variations in body temperature of springbok, like those of other free-living African ungulates, therefore appear to reflect an endogenous rhythm, entrained by the light:dark cycle, but largely independent of fluctuations in the environmental thermal load. Springbok exhibit remarkable homeothermy and do not employ adaptive heterothermy to survive in their natural environment.
我们在8只（3只雄性，5只雌性）成年野生跳羚（南非剑羚）的腹腔内植入微型数据记录器，在其自然栖息地每隔30分钟测量一次核心体温，持续11 - 13个月。这些动物经历的昼夜气温变化范围常常超过20摄氏度，绝对最低温度为零下6摄氏度，最高温度为34摄氏度。腹部温度呈现出低幅度（约1.2摄氏度）的昼夜节律，温度峰值出现在日落附近，谷值出现在日出后不久。体温的昼夜节律幅度与24小时气温变化范围无关。尽管24小时平均体温与相应的气温呈正相关，但气温每升高1摄氏度，平均每日体温仅平均升高0.02摄氏度，因此夏季平均体温仅比冬季高约0.3摄氏度。月平均体温与光照周期呈强正相关，并且与日出时间的变化平行，最低和最高体温出现的时间在夏季比冬季大约早1.2小时。因此，跳羚体温的年度和每日变化，与其他自由生活的非洲有蹄类动物一样，似乎反映了一种由光暗周期调节的内源性节律，但在很大程度上独立于环境热负荷的波动。跳羚表现出显著的恒温性，在其自然环境中并不采用适应性异温性来生存。
