2025 Volume 42 Issue 2 Pages 103-113
Behavioral laterality, exemplified by the dominant hand in humans, has been documented across many animals. While the laterality may seem puzzling and non-adaptive at first glance, it is believed to enhance locomotor performance and improve individual adaptive fitness. However, there have been few experimental studies investigating the developmental processes by which laterality is acquired after birth. The scale-eating cichlid fish, Perissodus microlepis, from Lake Tanganyika, eastern Africa, provides an excellent model for studying animal lateralization. This fish species shows a unique predation behavior, tearing scales off prey fish, and exhibits pronounced behavioral laterality during predation. Recent studies have revealed that this laterality is shaped by both genetic factors and feeding experience. Innate traits, such as the superiority of dominant-side attack kinetics and mandibular asymmetry, provide the foundation for laterality. However, feeding experience in early-life stage plays a critical role in reinforcing this behavior. The scale-eater learn which body side of the prey to attack, leading to a preference for the dominant-side at predation. Moreover, mandibular asymmetry develops throughout ontology and is positively correlated with predation success. Through the study of laterality in P. microlepis, it is expected that the neuronal and molecular mechanisms underlying animal lateralization, shedding light on this enigmatic phenomenon.
