Social entrainment of the circadian rhythm in the flight activity of the microchiropteran bat Hipposideros speoris
We investigated the problem of how members of the microchiropteran bat species Hipposideros speoris that live in a true cave clock their flight activity rhythms in the absence of time cues.
The bats become restless well in advance of sunset and then fly towards the cavemouth to sample light.
We investigated whether each bat roosting 40 m from the cave entrance must sample outside light levels for itself in order to emerge at the appropriate time. Three captive bats were tested and each began activity when the conspecifics left the cave in the evenings.
In another series of experiments a solitary bat was held captive in a solitary cave for 50 days and its circadian rhythm was recorded. In the absence of other conspecifics the circadian rhythm ‘free ran’ with a period shorter than 24 h.
We concluded from the results of our studies that there exists a clear-cut case for social synchronization of the circadian rhythms of this cave-dwelling bat.
KeywordsCircadian Rhythm Light Level Activity Rhythm Flight Activity Cave Entrance
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- Bovet J, Oertli EF (1974) Free-running circadian activity rhythms in free-living beaver (Castor canadensis). J Comp Physiol 92:1–10Google Scholar
- Buenning E (1973) The physiological clock (revised 3rd English ed). Springer, Berlin Heidelberg New YorkGoogle Scholar
- Crowley M, Bovet J (1980) Social synchronization of circadian rhythms in deer mice (Peromyscus maniculatus). Behav Ecol Sociobiol 7:99–105Google Scholar
- Erkert HG (1978) Sunset-related timing of flight activity in neotropical bats. Oecologia 36:59–67Google Scholar
- Gwinner E (1966) Periodicity of a circadian rhythm in birds by species-specific song cycles (Aves, Fringillidae: Carduelis spinus, Serinus serinus). Experientia 22:765–766Google Scholar
- Lohmann M, Enright JT (1967) The influence of mechanical noise on the activity rhythms of finches. Comp Biochem Physiol 22:289–296Google Scholar
- Marimuthu G, Subbaraj R, Chandrashekaran MK (1978) Social synchronization of the activity rhythm in a cave-dwelling insectivorous bat. Naturwissenschaften 65:600Google Scholar
- Pittendrigh CS, Minis DH (1964) The entrainment of circadian oscillations by light and their role as photoperiodic clocks. Am Nat 98:261–294Google Scholar
- Subbaraj R, Chandrashekaran MK (1977) ‘Rigid’ internal timing in the circadian rhythm of flight activity in a tropical bat. Oecologia 29:341–348Google Scholar
- Subbaraj R, Chandrashekaran MK (1978) Pulses of darkness shift the phase of a circadian rhythm in an insectivorous bat. J Comp Physiol 127:239–243Google Scholar
- Twente JR (1955) Some aspects of habitat selection and other behaviour of cavern-dwelling bats. Ecology 36:706–732Google Scholar
- Voûte AM, Sluiter JW, Crimm MP (1974) The influence of the natural light-dark cycle on the activity rhythm of pond bats (Myotis dasycneme Boie, 1825) during summer. Oecologia 17:221–243Google Scholar
- Wever RA (1979) The circadian system of man. Springer, Berlin Heidelberg New YorkGoogle Scholar