Chantal Véronique, Gibelli Julie, Dubois Frédérique
Département de sciences biologiques, Université de Montréal , Montréal , Canada.
PeerJ. 2016 Aug 31;4:e2409. doi: 10.7717/peerj.2409. eCollection 2016.
Experimental evidence suggests that females would prefer males with better cognitive abilities as mates. However, little is known about the traits reflecting enhanced cognitive skills on which females might base their mate-choice decisions. In particular, it has been suggested that male foraging performance could be used as an indicator of cognitive capacity, but convincing evidence for this hypothesis is still lacking. In the present study, we investigated whether female zebra finches (Taeniopygia guttata) modify their mating preferences after having observed the performance of males on a problem-solving task. Specifically, we measured the females' preferences between two males once before and once after an observation period, during which their initially preferred male was incapable of solving the task contrary to their initially less-preferred male. We also conducted a control treatment to test whether the shift in female preferences was attributable to differences between the two stimulus males in their foraging efficiency. Finally, we assessed each bird's performance in a color associative task to check whether females can discriminate among males based on their learning speed. We found that females significantly increased their preference toward the most efficient male in both treatments. Yet, there was no difference between the two treatments and we found no evidence that females assess male cognitive ability indirectly via morphological traits. Thus, our results suggest that females would not use the males' problem-solving performance as an indicator of general cognitive ability to gain indirect fitness benefits (i.e., good genes) but rather to assess their foraging efficiency and gain direct benefits.
实验证据表明,雌性会更倾向于选择认知能力更强的雄性作为配偶。然而,对于反映增强认知技能的特征,雌性在做出配偶选择决定时可能依据哪些特征,我们却知之甚少。特别是,有人提出雄性的觅食表现可作为认知能力的一个指标,但这一假设仍缺乏令人信服的证据。在本研究中,我们调查了雌性斑胸草雀(Taeniopygia guttata)在观察雄性在解决问题任务中的表现后,是否会改变它们的交配偏好。具体而言,我们在观察期前后各测量了一次雌性对两只雄性的偏好,在观察期内,它们最初偏好的雄性无法解决任务,而最初不太偏好的雄性却能解决。我们还进行了对照处理,以测试雌性偏好的转变是否归因于两个刺激雄性在觅食效率上的差异。最后,我们评估了每只鸟在颜色联想任务中的表现,以检查雌性是否能根据雄性的学习速度来区分它们。我们发现,在两种处理中,雌性对效率最高的雄性的偏好都显著增加。然而,两种处理之间没有差异,而且我们没有发现证据表明雌性会通过形态特征间接评估雄性的认知能力。因此,我们的结果表明,雌性不会将雄性的解决问题表现作为获得间接适应性益处(即优质基因)的一般认知能力指标,而是用于评估它们的觅食效率并获得直接益处。