Chronobiology
Author: Ariana Bertot | Email: arianabertot@gmail.com
Ariana Bertot1°, Esteban Javier Beckwith1°2°,Julieta Sztarker1°2°
1° IFIBYNE (CONICET-UBA)
2° Depto FBMC (FCEN-UBA)
Sleep is present in all animals in which it has been studied suggesting an early evolutionary appearance, and a very positive impact on fitness. Its biological importance is undoubted although the extent of its functions is still unknown. This period of relative disconnection from the external world is considered vitally important for multiple physiological and behavioral processes (such as learning and memory, tissue repair, for example). Different species have diverse sleeping habits, each displaying a specific sleep posture, adapted to its ecological niche and needs. According to the currently accepted model, sleep regulation is guided by two fundamental processes: the homeostatic sleep pressure, which ensures a daily balance of sleep, and the circadian rhythm, which aligns sleep with the day-night cycle. Although sleep has been explored in various animal models, including invertebrates, it has never been studied in intertidal animals. The crab Neohelice granulata is semiterrestrial, meaning that their activity/rest rhythm is guided by a third pressure, the circatidal rhythm, which marks the rise and fall of the tides. In this project we have started filming the crabs during several days to study their activity/rest rhythms and their postures during immobility. We aim to recognize the presence of sleep in crabs by finding specific postural patterns during immobility that coincide with a reduced alertness and which are increased after sleep deprivation or social exposure.