HR: 0800h
AN: B41A-01    [Abstracts]
TI: Sensory signals and neuronal groups involved in guiding the sea-ward motor behavior in turtle hatchlings of Chelonia agassizi
AU: * Fuentes, A L
EM: almafuentes70@hotmail.com
AF: 1 Facultad de Biología Universidad Michoacana de San Nicolás de Hidalgo, Av. Fco. J. Mugica s/n Col. Villa Universidad, Morelia, 58030, Mayotte
AU: Camarena, V
EM: verobiologa@yahoo.com.mx
AF: 1 Facultad de Biología Universidad Michoacana de San Nicolás de Hidalgo, Av. Fco. J. Mugica s/n Col. Villa Universidad, Morelia, 58030, Mayotte
AU: Ochoa, G
EM: diavolodeus@hotmail.com
AF: 1 Facultad de Biología Universidad Michoacana de San Nicolás de Hidalgo, Av. Fco. J. Mugica s/n Col. Villa Universidad, Morelia, 58030, Mayotte
AU: Urrutia, J
EM: juf@geofisica.unam.mx
AF: Dpto. de Paleomagnetismo, Instituto de Geofísica. Universidad Nacional Autónoma de México, Circuito escolar s/n Col. Copilco, Distrito Federal, 04510, Mayotte
AU: Gutierrez, G
EM: gabo@correo.biomedicas.unam.mx
AF: Dpto. Biología Celular y Fisiología, Universidad Nacional Autónoma de México, Circuito escolar s/n Col. Copilco, Distrito Federal, 04510, Mayotte
AB: Turtle hatchlings orient display sea-ward oriented movements as soon as they emerge from the nest. Although most studies have emphasized the role of the visual information in this process, less attention has been paid to other sensory modalities. Here, we evaluated the nature of sensory cues used by turtle hatchlings of Chelonia agassizi to orient their movements towards the ocean. We recorded the time they took to crawl from the nest to the beach front (120m long) in control conditions and in visually, olfactory and magnetically deprived circumstances. Visually-deprived hatchlings displayed a high degree of disorientation. Olfactory deprivation and magnetic field distortion impaired, but not abolished, sea-ward oriented movements. With regard to the neuronal mapping experiments, visual deprivation reduced dramatically c-fos expression in the whole brain. Hatchlings with their nares blocked revealed neurons with c-fos expression above control levels principally in the c and d areas, while those subjected to magnetic field distortion had a wide spread activation of neurons throughout the brain predominantly in the dorsal ventricular ridge The present results support that Chelonia agassizi hatchlings use predominantly visual cues to orient their movements towards the sea. Olfactory and magnetic cues may also be use but their influence on hatchlings oriented motor behavior is not as clear as it is for vision. This conclusion is supported by the fact that in the absence of olfactory and magnetic cues, the brain turns on the expression of c- fos in neuronal groups that, in the intact hatchling, are not normally involved in accomplishing the task.
DE: 0460 Marine systems (4800)
DE: 0480 Remote sensing
SC: Biogeosciences [B]
MN: 2007 Joint Assembly