Sexual selection and predator response in a male-polymorphic livebearing fish

Sexual polymorphism describes discrete variation among individuals of one sex, often involving conspicuously colored, displaying male morphs and inconspicuous, sneaking male morphs. Sexual polymorphism may be maintained over evolutionary time if the displaying morph is favored by sexual selection and the sneaking morph experiences reduced predation. We tested these ideas using 3D printed models and live males in the sexually polymorphic poeciliid fish, Girardinus metallicus. Females did not prefer the displaying black morph; however, black morphs exhibited more male-male aggression, and dominant black morph males achieved higher mating success than all plain morph males, suggesting a sexual selection advantage. Predatory blue tilapia (Oreochromis aureus) did not show a preference for either morph, suggesting no plain morph advantage in this regard that would maintain the polymorphism. It is possible that the polymorphism is instead maintained because as black morphs become common, aggre..., Data were collected by direct observation for behaviors and measurement from digital images for body size. Data analysis was performed using JMP Pro 17., , # Sexual selection and predator response in a male-polymorphic livebearing fish

[https://doi.org/10.5061/dryad.hhmgqnkrc](https://doi.org/10.5061/dryad.hhmgqnkrc)

## Description of the data and file structure

These data were collected for an experimental study examining sexual selection and predator reaction comparing the two male morphs of the poeciliid fish, *Girardinus metallicus. *We employed dichotomous choice tests and direct interaction tests to quantify sexual selection across morphs, and dichotomous choice tests to quantify the reaction of blue tilapia (*Oreochromis aureus*) to males of each morph.

1\. Title of Dataset: Sexual selection and predator response in a male-polymorphic livebearing fish

2\. Author Information

A. Principal Investigator Contact Information

Name: Gita R. Kolluru

Institution: California Polytechnic State University

Address: San Luis Obispo, CA USA

Email: [[e-mail] (opens in new window)](mailto:[e-mail])

3\. Date of data ...

性多态性（Sexual polymorphism）指同一性别个体间存在的离散型变异，通常涵盖体色醒目、具有展示行为的雄性形态，以及体色隐蔽、采取偷配策略的雄性形态。若展示型雄性受到性选择青睐，而偷配型雄性遭遇的捕食压力更低，则性多态性可在进化历程中得以维持。本研究以具有性多态性的花鳉科鱼类——金属剑尾鱼（*Girardinus metallicus*）为研究对象，借助3D打印模型与活体雄性个体开展实验，对上述假说进行验证。结果表明，雌性并未表现出对展示型黑色雄性形态的偏好；然而，黑色雄性个体展现出更强的雄性间攻击行为，且优势黑色雄性的交配成功率显著高于所有普通形态雄性，这提示黑色形态拥有性选择优势。捕食性的蓝色罗非鱼（*Oreochromis aureus*）未表现出对任一雄性形态的偏好，这意味着本实验中普通形态并未获得可维持多态性的捕食逃避优势。推测该多态性的维持可能源于：当黑色雄性形态种群密度升高时，攻击行为相关的……（原文此处截断为aggre...）。行为数据通过直接观察法获取，体型数据则通过数码图像测量得到。数据分析采用JMP Pro 17软件完成。

# 雄性多态性胎生鱼类的性选择与捕食者响应
https://doi.org/10.5061/dryad.hhmgqnkrc

## 数据与文件结构说明
本数据集源自一项实验研究，旨在探究雄性多态的花鳉科鱼类*Girardinus metallicus*的两种雄性形态在性选择与捕食者反应方面的差异。研究采用二选一选择实验与直接互动实验，量化不同雄性形态间的性选择强度；同时通过二选一选择实验，量化蓝色罗非鱼（*Oreochromis aureus*）对各雄性形态的捕食反应。

1. 数据集标题：雄性多态性胎生鱼类的性选择与捕食者响应
2. 作者信息
A. 项目负责人联系方式
姓名：吉塔·R·科鲁鲁（Gita R. Kolluru）
所属机构：加州州立理工大学（California Polytechnic State University）
通讯地址：美国加利福尼亚州圣路易斯奥比斯波
电子邮箱：[e-mail]
3. 数据收集日期……（原文此处未完整给出）