Proximate causes of Rensch's rule: Does sexual size dimorphism in arthropods result from sex differences in development time?
Proximate causes of Rensch's rule: Does sexual size dimorphism in arthropods result from sex differences in development time?
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DOI：
10.1086/510597
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发表时间：
2007-02-01
影响因子：
2.9
通讯作者：
Wiklund, Christer
中科院分区：
文献类型：
--
作者：
Blanckenhorn, Wolf U.;Dixon, Anthony F. G.;Wiklund, Christer
性别体型二态性 (SSD) 的一个突出的种间模式是伦施规则，根据该规则，雄性体型比雌性体型变化更大或在进化上差异更大。假设男性和女性的增长率相同，SSD将完全由发育时间的性别差异或性两性成熟（SBM）所调节，即伦施规则，其中较大的性别发育的时间相对较长。本研究调查的七个节肢动物群中只有一部分表现出伦施规则。此外，我们发现 SSD 和 SBM 之间总体上只有微弱的正相关关系，这表明在广泛但绝不是全面的节肢动物类群中，性别之间的增长率差异比直接介导 SSD 的发育时间差异更重要。除非先祖性具有选择优势（如许多蝴蝶、膜翅目和蜘蛛），雄性发育时间等于（水黾和甲虫）甚至长于雌性（果蝇和败血症蝇）。由于所有类群均显示雌性偏向 SSD，这意味着雌性总体上生长较快，这种模式与灵长类动物和鸟类明显不同（此处进行分析以进行比较）。我们根据生活史权衡和性选择讨论了这种模式的三种可能的解释。
A prominent interspecific pattern of sexual size dimorphism (SSD) is Rensch's rule, according to which male body size is more variable or evolutionarily divergent than female body size. Assuming equal growth rates of males and females, SSD would be entirely mediated, and Rensch's rule proximately caused, by sexual differences in development times, or sexual bimaturism (SBM), with the larger sex developing for a proportionately longer time. Only a subset of the seven arthropod groups investigated in this study exhibits Rensch's rule. Furthermore, we found only a weak positive relationship between SSD and SBM overall, suggesting that growth rate differences between the sexes are more important than development time differences in proximately mediating SSD in a wide but by no means comprehensive range of arthropod taxa. Except when protandry is of selective advantage ( as in many butterflies, Hymenoptera, and spiders), male development time was equal to ( in water striders and beetles) or even longer than ( in drosophilid and sepsid flies) that of females. Because all taxa show female-biased SSD, this implies faster growth of females in general, a pattern markedly different from that of primates and birds (analyzed here for comparison). We discuss three potential explanations for this pattern based on life-history trade-offs and sexual selection.