Motor asymmetries in fishes, amphibians, and reptiles

The study of brain and behavioral lateralization in so-called “lower vertebrates” (fish, amphibians, and reptiles) has received increasing attention in the last years, in an attempt to under- stand its phylogenetic origins and evolutionary significance. Observations on the earliest tetrapods, the amphibians, have helped us to understand the evolution of limb preference and suggest that laterality could have appeared even prior to the evolution of tetrapods. Insights into lateralized behaviors in fish—such as the turning behavior—have had an important role in uncovering proximate and ultimate causes of motor lateralization in the vertebrate subphylum. Additionally, investigations on the alignment of behavioral preferences in fish populations have helped do develop formal models to explain the unequal distribution of left- and right-lateralized individuals as the result of evolutionarily stable strategies among lateralized asymmetric individuals that interact cooperatively or competitively.