Social synchronization of circadian rhythms in deer mice (Peromyscus maniculatus)

Social synchronization of circadian locomotor activity rhythm in the fruit fly Drosophila melanogaster

“…Other organisms such as mice and beavers show an effect of social interactions on the circadian period (Halberg et al, 1954;Bovet and Oertli, 1974;Crowley and Bovet, 1980). Our study showed that social interactions among flies with different periods did not cause a measurable change in circadian period when made to interact one-on-one, except when per S and per L flies were paired together (Fig.1A).…”

“…These results suggest that social cues are able to synchronize circadian clocks when the periods of the interacting flies are similar, implying that social interactions are relatively weak synchronizing cues for Drosophila circadian clocks. Social synchronization alters the circadian period of interacting flies only in cases when the per L strain was involved either directly or indirectly (Fig.1B,C) (Crowley and Bovet, 1980), wherein the phase synchrony of mice living in groups was found to be achieved by period changes. Furthermore, in a previous study, Levine and coworkers (Levine et al, 2002) would make them more sensitive to social cues compared with their faster interacting partners (through some unknown mechanisms).…”

“…Similarly, when hamster males were subjected to phase advancement in LD cycles by 8h, their rhythms entrained faster when they were presented with females in estrous; however, mating with such females had a negative impact on the rate of reentrainment (Honrado and Mrosovsky, 1989). In a separate study, it was shown that mice with variable circadian periods displayed synchronized behaviour as long as they were maintained together in a group (Crowley and Bovet, 1980). Similarly, members of a family of free-living beavers (Castor canadensis) displayed a synchronized period of ~27h when confined as groups to caves in winters, only to return to a 24h entrained rhythm in summers (Bovet and Oertli, 1974), suggesting that social cues maintain phase synchrony between interacting individuals.…”

Acoustic ecology of Antarctic pinnipeds

“…Animals across various taxa inhabiting environments that lack time cues are known to socially and mutually synchronize circadian rhythms (e.g. Crowley & Bovet 1980, Marimuthu et al 1981, Aschoff et al 1983. Similarly, Weddell seals might use the vocalizations of conspecifics to synchronize their own vocal activity.…”

Early to rise, early to breed: a role for daily rhythms in seasonal reproduction

“…The daily light-dark cycle, social interactions and other environmental cues entrain the circadian system to a period of 24 h (Crowley and Bovet 1980;Johnson et al 2003;Dunlap et al 2004), thus making it impossible to measure the endogenous free-running circadian period of an individual in the wild. Alternatively, we can measure the phenotypic output of circadian rhythms by measuring the chronotype, or the timing exhibited by an individual relative to a salient environmental cue (e.g.…”