Assertion: house sparrow | /r/HasProperty | exposed playback
Facets:
value: to two hours of chirp
type: TEMPORAL
Source sentences:
text: House sparrows have also been used in studies of nonphotic entrainment (i.e. synchronisation to an external cycle other than light and dark): for example, in constant darkness, a situation in which the birds would normally reveal their endogenous, non-24-hour, "free-running" rhythms of activity, they instead show 24-hour periodicity if they are exposed to two hours of chirp playbacks every 24 hours, matching their daily activity onsets with the daily playback onsets.