IFIBYNE   05513
INSTITUTO DE FISIOLOGIA, BIOLOGIA MOLECULAR Y NEUROCIENCIAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Changes in hiding behaviour and the nervous system during the post-embryonic development of the locust Locusta migratoria
Autor/es:
JULIETA SZTARKER; F CLAIRE RIND
Lugar:
Newcastle upon Tyne
Reunión:
Congreso; Northeast Meeting on Evolution, Brains and Behaviour; 2011
Resumen:
Looming detection is crucial for animals to respond efficiently and escape from approaching stimuli. Using locusts as experimental models, extensive research has been done to characterise the neural circuits underlying this capacity. Until now, these studies have been conducted in adult locusts. Nonetheless, these animals avoid predation by birds throughout their lives and the preferred escape response displayed varies during development. The hiding response involves a positioning behaviour in which locusts sitting on branches or leaves tend to hide from an approaching stimulus by moving behind the object. The neural circuit underlying this behaviour is unknown. Because hiding responses are triggered by looming stimuli it is possible that the LGMD-DCMD system is involved. In this study we analysed the hiding responses displayed at different stages of the locust’s life (first to fifth instars and adult). Although hiding responses were identified in all developmental stages, the proportion of animals displaying such responses changes dramatically in the different instars. Other parameters that are modified during development are the response latency (and thus the subtended angle of the looming object at the time of response), the response velocity and the angle of rotation performed during the response. Our results could be explained by a change in the behavioural strategy opted for by locusts at each instar or it could be correlated with an uneven maturation of the nervous system with some circuits developing earlier than others, or even by a change in visual acuity during development, particularly in the early instars. To asses the likelihood of these different explanations, we used Bodian’s original reduced-silver method to reveal the neuroarchitecture of the optic lobes in each of the instars. An attempt was also made using Neurolucida to reconstruct the LGMD1 and LGMD2 neurons to reveal the presence and state of development of these neurons in different instars.