Trial marriage model—Female mate choice under male interference. Issue 8 (14th May 2020)

• Record Type: Journal Article
• Authors: Li, Meng‐Yao; Geng, Zhuo‐Song; Liao, Peng; Wang, Xiao‐Yang; Yang, Tian‐Chang; Wang, Jing‐Yuan; Wang, Dan‐Dan; Gao, Li‐Fang; Du, Bo
• Editors: Tate, Ann
• Is Part Of: Journal of animal ecology. Volume 89:Issue 8(2020)
• Page Start: 1851
• Page End: 1859
• Publication Date: 2020-05-14
• Subjects: male–male competition -- mate choice -- mating interference -- mating partner -- social pair formation -- trial marriage; Animal ecology -- Periodicals; 591.7
• DOI: 10.1111/1365-2656.13240
• Languages: English
• ISSNs: 0021-8790

Abstract

Abstract: In sexually reproducing animals, the process of mate choice by females is often mixed with the process of male–male competition. Current models of female male choice focus mainly on how females identify the higher quality of males, but neglect the effect of male–male competition on the mate choice of females. Therefore, it remains controversial what is the relative importance of two processes in forming a social bond. We propose a new 'trial marriage' model for females' mate choice. The model assumes that females unconditionally accept any male they first encounter as their mating partner, and then conditionally switch mates to a new male of higher quality than their current partner when male–male competition occurs. This model was tested in the green weevil Hypomeces squamosus by exploring how females switched mates when males' mating interference was experimentally induced. The likelihood that females switched mates, as well as their conditional acceptance criteria of a new mate, was both raised with the intensity of males' mating interference that was manipulated in an enhanced encounter rate experiment, and in male introduction or stepwise removal experiments. These experimental findings confirm that a 'trial marriage' strategy occurs during females' mate choice. Compared with other strategies, it is more beneficial for females to choose a better mate without paying the costs of identifying males as suggested by the 'trial marriage' strategy. More importantly, using the current partner quality as the conditional acceptance threshold of new mates, females can choose better males in future encounters with potential mates. In the green weevils, males' preference for larger females and the higher possibility of the largest male winning an interference are mixed together when males' mating interference reaches a higher intensity. Therefore, the consequence of a male interference will determine which male could be chosen by a female. Under this condition, conditional acceptance of the winner becomes the most beneficial strategy of females in choosing their mates. We thus suggest that the 'trial marriage' strategy would be more efficient when males' mating interference becomes the determinant factor of females' mate choice. Abstract : The authors propose and experimentally confirm a new 'trial marriage' strategy for females' mate choice in the green weevil, which might become an important alternative to existing mate choice strategies of females. 摘要: 在有性生殖的动物中，雌性选择配偶的过程与雄性争夺配偶的过程常常混杂在一起。现有的关于雌性择偶的模型重点关注雌性怎样识别更高质量的雄性，而忽略了雄性间竞争对雌性择偶的影响。因此，雌、雄在配对建立过程中的作用孰轻孰重仍然存有争议。 在本研究中，我们提出了一个新的"试婚"模型来阐释雌性的择偶策略。该模型认为，雌性首先无条件地接受她最早遇到的任何雄性作为交配对象，然后在雄性间竞争发生时有条件地更换配偶，从而使得新配偶的质量比原来的交配对象更高。 在绿象甲中，我们设计了一系列实验，包括配偶遭遇率增高实验、新雄引入实验和雄性逐步移除实验，来控制雄性交配干扰的发生及强度。通过检测实验过程中雌性更换配偶的条件及影响因子，对"试婚"模型进行了验证。 实验结果表明，雌性更换配偶的概率以及她们有条件地接受新配偶的标准，都随着雄性交配干扰强度增加而增加，证明了雌性在择偶过程中的确采取了"试婚"策略。 与已知的其它雌性择偶策略相比，"试婚"策略更高效，因为雌性不再需要对雄性就行甄别就能选到高质量的雄性。更重要的是，以当前配偶的质量作为接受新雄性的条件性阈值，雌性在未来遭遇其他雄性时能够更换更高质量的配偶。在绿象甲中，我们还发现雄性在求偶过程中偏好更大的雌性，而在雄性交配干扰过程中体型大的更容易获胜。二者在雄性交配干扰达到一定强度后会产生协同效应，使得雄性交配干扰的结果成为雌性择偶的决定因子。在这种情况下，有条件地接受雄性交配干扰中的胜利者成为雌性择偶的最佳策略。因此，我们认为雌性的这种"试婚"策略将随着雄性间竞争强度的增加而变得更高效。