Males and females of nearly all animals differ in their body size, a phenomenon called sexual size dimorphism (SSD). The degree and direction of SSD vary considerably among taxa, including among populations within species. A considerable amount of this variation is due to sex differences in body size plasticity. We examine how variation in these sex differences is generated by exploring sex differences in plasticity in growth rate and development time and the physiological regulation of these differences (e.g., sex differences in regulation by the endocrine system). We explore adaptive hypotheses proposed to explain sex differences in plasticity, including those that predict that plasticity will be lowest for traits under strong selection (adaptive canalization) or greatest for traits under strong directional selection (condition dependence), but few studies have tested these hypotheses. Studies that combine proximate and ultimate mechanisms offer great promise for understanding variation in SSD and sex differences in body size plasticity in insects.

中文翻译：

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表型可塑性的性别差异影响昆虫性别大小二态性的变化：从生理学到进化。

几乎所有动物的雄性和雌性的体型都不同，这种现象称为性别体型二态性（SSD）。SSD 的程度和方向在不同类群之间差异很大，包括物种内的种群之间。这种差异很大程度上是由于身体尺寸可塑性的性别差异造成的。我们通过探索生长速率和发育时间可塑性的性别差异以及这些差异的生理调节（例如内分泌系统调节的性别差异）来研究这些性别差异的变化是如何产生的。我们探索了为解释可塑性性别差异而提出的适应性假设，包括预测在强选择（适应性渠道化）下性状的可塑性最低或在强定向选择（条件依赖性）下性状的可塑性最高的假设，但很少有研究测试这些假设。结合近因机制和终极机制的研究为理解昆虫 SSD 的变化和体型可塑性的性别差异提供了巨大的希望。