ABSTRACT
Aggressive competition for resources among juveniles is documented in many species, but the neural mechanisms regulating this behavior in young animals are poorly understood. In poison frogs, increased parental care is associated with decreased water volume of tadpole pools, resource limitation, and aggression. Indeed, the tadpoles of many poison frog species will attack, kill, and cannibalize other tadpoles. We examined the neural basis of conspecific aggression in Dendrobates tinctorius poison frog tadpoles by comparing individuals that won aggressive encounters, lost aggressive encounters, or did not engage in a fight. We compared patterns of generalized neural activity as well as activity specifically in nonapeptide (arginine vasotocin and mesotocin) and dopaminergic cells. We found increased neural activity in the medial pallium and preoptic area of losers, but increased neural activity specifically in the preoptic area nonapeptide neurons of winners. We found no differences in activity of dopaminergic cells among behavioral groups. This study is the first to examine the neural mechanisms of aggression in amphibian larvae. Our findings suggest the neural correlates of aggression in poison frog tadpoles are similar to neural mechanisms mediating aggression in adults and juveniles of other vertebrate taxa.








