Genotype-by-environment interactions for precopulatory mate guarding in a lek-mating insect

In sexually reproducing species males often experience strong pre- and postcopulatory sexual selection leading to a wide variety of male adaptations. One example is mate guarding, where males prevent females from mating with other males either before or after they (will) have mated themselves. In case social conditions vary short-term and in an unpredictable manner and if there is genetic variation in plasticity of mate guarding (i.e. genotype-by-environment interaction, G x E), adaptive behavioral plasticity in mate guarding may evolve.
Here, we test for genetic variation in the plasticity of precopulatory mate guarding behavior in the lek-mating lesser wax moth Achroia grisella. When offered two females in rapid succession, virgin males of this species usually copulate around 10-20 min with the first female. With the second female, however, they engage in copulation posture for many hours until they have produced another spermatophore, an unusual behavior among insects possibly functi...

在有性繁殖的物种中，雄性往往会受到强烈的交配前性选择（precopulatory sexual selection）与交配后性选择（postcopulatory sexual selection）作用，进而演化出多种多样的雄性适应性特征。其中一个典型例子是配偶守护（mate guarding）：即雄性在自身完成交配前或后，阻止雌虫与其他雄虫进行交配。若社会环境存在短期且不可预测的波动，且配偶守护的可塑性存在遗传变异（即基因型-环境互作，genotype-by-environment interaction，G×E），则配偶守护行为的适应性行为可塑性可能得以演化。

本研究以求偶场交配（lek-mating）的小蜡螟（Achroia grisella）为实验对象，检测其交配前配偶守护行为可塑性的遗传变异。当该物种的未交配雄虫连续快速接触两只雌虫时，通常会与第一只雌虫进行约10~20分钟的交配。但当与第二只雌虫配对时，雄虫会维持交配姿势长达数小时，直至再次生成精荚（spermatophore）；这类行为在昆虫中较为罕见，其潜在功能尚待探讨（原文截断）。