Environmental control of annual testicular cycles in the lizard Anolis carolinensis. I. Interaction of light and temperature in the initiation of testicular recrudescence.
Environmental control of annual testicular cycles in the lizard Anolis carolinensis. I. Interaction of light and temperature in the initiation of testicular recrudescence.
复制标题
蜥蜴 Anolis carolinensis 年度睾丸周期的环境控制。
DOI：
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发表时间：
1967
期刊：
影响因子：
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通讯作者：
Paul Licht
中科院分区：
文献类型：
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作者：
Paul Licht
从9月中旬开始，在不同光照和温度条件下，对卡罗来纳山羊雄性成虫睾丸复发起始的环境因子进行了研究。TR通常在秋季开始，整个冬季逐渐进行，并在早春完成。这种模式似乎每年都非常相似。当体温在32℃恒定时，每天光照14小时，TR显著加快；或者当体温波动以模拟正常的热循环（白天32°，晚上20°）时。后一种情况下出现明显的睾丸周期。如果每天在晚上加热（32°C）（白天加热20°C），那么长时间的白天几乎没有反应。在体温保持在32°C恒定的情况下，每天12或6小时的光照周期，与自然界中的动物或保持在恒定低体温（20°C）下的动物相比，会导致TR延迟。然而，一旦TR开始，它就会被高温加速。
Adult male Anolis carolinensis were placed under several combinations of light and temperature starting in midSeptember to elucidate the environmental factors regulating the initiation of testicular recrudescence (TR). TR normally starts in the fall, proceeds gradually throughout the winter, and is completed in early spring. This pattern appears to be very similar from year to year. TR was greatly accelerated by 14 hours of light daily when body temperatures were kept constant at 32°C; or when body temperatures were fluctuated to emulate a normal thermal cycle (day 32°, night 20°). A pronounced testicular cycle occurred under the latter conditions. If the daily heating (32°) was given at night (with 20°C during the daytime) there was virtually no response to long day-lengths. A photoperiod consisting of 12 or 6 hours of light daily, with body temperature kept constant at 32°C caused a delay in TR as compared to animals in nature or to those kept at a constant low body temperature (20°C). However, once TR began, it was accelerated by the high temperature.
Photoperiods of 0 to 14 hours of light daily had no influence on the initiation or rate of TR at 20°C. Testes developed at approximately the same rate as in nature. After 150 days, the testes were unusually enlarged but spermatogenic activity was still low.
These data suggest that even though a distinct photoperiodism is evident in Anolis, day-length probably acts only in a permissive way to facilitate the temperature response which is the more direct modifier of TR. Different aspects of TR may have different thermal requirements. TR may be spontaneously initiated by an “endogenous trigger” and then modified by the thermal relations of the animal.