intrasexual selection

例句：

1. 1. Intrasexual selection is a phenomenon where individuals choose their mates based on characteristics that are not directly related to fertility or survival.
   内择配偶是一种现象，其中个体基于与繁殖力或生存无关的特征来选择他们的配偶。
2. 2. This theory suggests that in some species, males may select females based on traits that enhance their ability to reproduce, rather than solely on physical appearance.
   这一理论表明，在有些物种中，雄性可能基于能提高其繁殖能力的特性来选择雌性，而不仅仅是基于外表。
3. 3. The process of intrasexual selection has been observed in many animal species, including humans, where males may preferentially mate with females who share similar genetic backgrounds.
   内择配偶的过程已在许多动物物种中观察到，包括人类，其中雄性可能偏好与具有相似遗传背景的雌性交配。