CONICET | Buscador de Institutos y Recursos Humanos

Interpopulation comparisons in species that show behaviouralvariations associated with particular ecological disparities offergood opportunities for assessing how environmental factors mayfoster specific functional adaptations in the brain. Yet, studies on theneural substrate that can account for interpopulation behaviouraladaptations are scarce. Predation is one of the strongest drivingforces for behavioural evolvability and, consequently, for shapingstructural and functional brain adaptations. We analysed the escaperesponse of crabs Neohelice granulata from two isolated populationsexposed to different risks of avian predation. Individuals from thehigh-risk area proved to be more reactive to visual danger stimuli(VDS) than those from an area where predators are rare. Controlexperiments indicate that the response difference was specific forimpending visual threats. Subsequently, we analysed the response toVDS of a group of giant brain neurons that are thought to play a mainrole in the visually guided escape response of the crab. Neurons fromanimals of the population with the stronger escape response weremore responsive to VDS than neurons from animals of the lessreactive population. Our results suggest a robust linkage between thepressure imposed by the predation risk, the response of identifiedneurons and the behavioural outcome.