Preliminary evidences of circadian fan activity rhythm in Sabella spallanzanii (Gmelin, 1791) (Polychaeta: Sabellidae)

• Autores: Jacopo Aguzzi, Juan J. Chiesa, Riccardo Caprioli, Davide Cascione, Giuseppe Magnifico
• Localización: Scientia Marina, ISSN 0214-8358, Vol. 70, Nº. 4, 2006, págs. 727-734
• Idioma: inglés
• Enlaces
  • Texto completo
• Dialnet Métricas: 1 Cita
• Resumen

  • The fan activity rhythm of Sabella spallanzanii (Gmelin, 1791) and its entrainment capability to light were studied. Animals were tested under constant darkness (DD) followed by two consecutive 24 h light-darkness regimes: a first 11 h light period (LD) and a second 9 h light period, with its phase inverted (DL). An infrared analogical video-camera took shots each 30 s. A number of pictures with open fan were counted every 15 min. In DD a weak free-running periodicity in the circadian range was found, thus reinforcing the matching of the 24 h period under study in both photoperiod regimes. A nocturnal activity was characterised with a consistent anticipation to lightOFF (i.e. entrainment). Moreover, this phase of entrainment differed between DL and LD. The presence of endogenous activity rhythm with a variable phase angle of entrainment is a distinctive feature of circadian pacemakers.