Biogéosciences, CNRS UMR 6282, Université de Bourgogne, 6 Bd Gabriel, 21000 Dijon, France.
Department of Zoology, University of Otago, PO Box 56, Dunedin 9054, New Zealand; Research Office, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand.
J Therm Biol. 2014 May;42:40-5. doi: 10.1016/j.jtherbio.2014.02.021. Epub 2014 Mar 12.
Animals that can be active both during day and night offer unique opportunities to identify factors that influence activity pattern. By experimental manipulations of temperatures under constant photoperiod, we aimed to determine if emergence, activity and thermoregulatory behaviour of juvenile tuatara (Sphenodon punctatus) varied at different temperatures (20°C, 12°C and 5°C). To help clarify its activity pattern, we compared tuatara with two lizard species endemic of the South Island of New Zealand for which activity pattern is known and clearly defined: the nocturnal common gecko Woodworthia "Otago/Southland" and the diurnal McCann׳s skink Oligosoma maccanni. Tuatara showed similar responses to both species of lizards. Similar to the diurnal skinks, tuatara emerged quickly at 20°C and 12°C while nocturnal geckos took more time to emerge. Like nocturnal geckos, tuatara continued to be active at 5°C, but only during the day. Interestingly, tuatara shifted from diurno-nocturnal activity at 20°C and 12°C to being strictly diurnal at 5°C. We suggest that this temperature-dependent strategy maximises their survival during cold periods.
那些可以在白天和晚上都活动的动物为识别影响活动模式的因素提供了独特的机会。通过在恒定光周期下对温度进行实验操作，我们旨在确定幼年大蜥蜴（Sphenodon punctatus）的出现、活动和体温调节行为是否会因不同温度（20°C、12°C 和 5°C）而有所不同。为了帮助阐明其活动模式，我们将大蜥蜴与两种已知且明确界定活动模式的新西兰南岛特有蜥蜴进行了比较：夜行性普通壁虎 Woodworthia“Otago/Southland”和日行性 McCann 石龙子 Oligosoma maccanni。大蜥蜴对这两种蜥蜴的反应相似。与日行性石龙子相似，大蜥蜴在 20°C 和 12°C 时迅速出现，而夜行性壁虎则需要更长时间才能出现。与夜行性壁虎一样，大蜥蜴在 5°C 时仍保持活跃，但仅在白天。有趣的是，大蜥蜴从 20°C 和 12°C 的昼夜活动转变为 5°C 时的严格日间活动。我们认为，这种温度依赖性策略最大限度地提高了它们在寒冷时期的生存能力。
