Feeding strategies of an organism depend on the multimodal sensory processing that most efficiently integrates available visual, chemosensory, and/or mechanoreceptive cues as part of their environmental adaptation. The blind cavefish morph of Astyanax mexicanus has developed sensory-dependent behaviors to find food more efficiently than their eyed, surface-morph counterparts while in darkness. In the absence of light, adult cavefish have evolved enhanced behaviors, such as vibration attraction behavior (VAB), and changes in feeding angle. Here, we identified evolved differences in cavefish larval prey capture (LPC) behavior. In the dark, LPC is more efficient in cavefish than in surface fish. Furthermore, different cave populations express laterality in their LPC and strike towards prey preferentially located on their left or right sides. This suggests the occurrence, to some extent, of divergent LPC evolution among cave populations. While LPC can be triggered exclusively by a vibration stimulus in both surface and cavefish, we provide evidence that LPC is, at least partially, a multimodal sensory process different from adult VAB. We also found that a lack of food may exacerbate the laterality of LPC. Thus, we proposed a mathematical model for explaining laterality based on a balance between: (1) enlarged range of foraging field (behavioral or perceptive) due to asymmetry, (2) food abundance, and (3) disadvantages caused by laterality (unequal lateral hydrodynamic resistance when swimming, allocation of resources for the brain and receptors, and predator escape).
作为环境适应的一部分，生物的摄食策略取决于最有效地整合视觉，化学感觉和/或机械感觉线索的多模式感觉处理。在黑暗的环境中，与有眼睛的表层鱼相比，墨西哥脂鲤（Astyanax mexicanus）洞穴鱼已进化出依赖感觉的摄食行为，能更有效的找到食物。而在没有光线的情况下，成年洞穴鱼进化出强化的行为，例如波动吸引行为（VAB）和摄食角度的变化。在该研究中，我们发现了洞穴鱼幼鱼摄食行为的进化差异。在黑暗中，洞穴幼鱼的LPC比表层鱼更高效。此外，不同的洞穴种群在其捕食行为中表现出侧向性，即优先攻击位于其左侧或右侧的猎物。这表明洞穴鱼种群之间存在不同的捕食行为进化策略。虽然表层鱼和洞穴鱼的捕食行为只能由振动刺激触发，但我们提供的证据表明，幼鱼捕食行为至少部分是一种不同于成体波动吸引行为的多模式感觉处理方式。我们还发现，缺乏食物可能会加剧LPC的侧向性。因此，我们提出了一个数学模型来解释侧向性，该模型基于以下因素之间的平衡：（1）由于不对称而扩大的觅食范围（行为或感知），（2）食物丰度，以及（3）侧向性导致的不利因素（游泳时的两侧水阻力不均衡、大脑和受体的资源分配以及躲避捕食者等）。.
Keywords: Astyanax; Asymmetry; Cave; Neuromast; Prey; Troglobite.