Morphological variation is widespread, and one case is that of female morphs in damselfly insects. Current knowledge indicates that these female morphs are maintained by a fitness balance whereby male-like, clear-colored females (i.e. andromorphs) are more likely to “escape” from male harassment given their male mimicking compared to dark females (i.e. gynomorph). However, males can learn to distinguish the more frequent morph, leading to a frequency-dependent selection. Alternative to frequency-dependent selection, we tested whether temperature plays a role in driving female morph activity and survival. We used Ischnura denticollis damselflies to test for differences between female morphs and males in: (a) daily activity; (b) time to resume activity following a chilling event (10°C); and, (c) survival at 30, 35 and 40°C. There was no difference in activity among groups after a chilling event. However, gynomorph females were more active early in the day (ca. 17°C) and less active by 1600 hrs (after reaching 32°C), and had lower thermal tolerance than andromorph females. Thus, high temperatures may act against gynomorph females. This implies a role for high temperatures in the maintenance of female polymorphism.

形态变化是普遍的，其中一个例子是豆娘昆虫中的雌性形态。当前的知识表明，这些女性形态是通过适应性平衡来维持的，与深色女性（如雌雄同体）相比，像男性一样色泽清晰的女性（即雄性形态）在模仿男性时更容易摆脱男性骚扰。但是，雄性可以学会区分频率更高的变体，从而导致依赖于频率的选择。除了依赖于频率的选择之外，我们测试了温度是否在驱动女性形态活动和生存中起作用。我们用了伊斯努拉树胶豆娘在以下方面测试女性形态与男性之间的差异：（a）日常活动；（b）在寒冷事件（10℃）后恢复活动的时间；（c）在30、35和40°C下的存活率。感冒事件后各组之间的活动没有差异。但是，雌雄同体雌性在一天中的早期（约17°C）更加活跃，而在1600小时（达到32°C之后）则没有那么活跃，并且耐热性低于雄雄雄性雌性。因此，高温可能对雌雄同体起作用。这暗示着高温在维持女性多态性中的作用。