Danio rerio are vertebrates, neural function and connectivity will share similarities to other vertebrates, like mice and humans. As such, findings from zebrafish can more readily be generalized to humans. Further, at the stage of development we use zebrafish for research (0-14 dpf), the animals have relatively few neurons. In fact, zebrafish (5 dpf) have about the same number of neurons as a fruit fly. The vertebrate nervous system, useful biological attributes (i.e., small size and translucency), and an ever-expanding set of molecular tools make zebrafish an ideal species to understand, at a basic level, the function/dysfunction of the nervous system.