AJP - Regulatory, Integrative and Comparative Physiology, Vol 247, Issue 6 1083-R1087, Copyright © 1984 by American Physiological Society
Two kinds of timing in circadian incubation rhythm of ring doves
J. Gibbon, M. Morrell and R. Silver
Ring dove males share incubation with females by sitting on the nest for a
block of time in the middle of the day. The timing of nest exchanges was
studied by experimentally delaying the onset, in the morning, of the male's
sitting bout. Such delays induced a concomitant but smaller delay in the
offset of the male's sitting bout in the afternoon. The female, however,
approached the nest to start her bout of sitting at the usual time in the
afternoon even though her previous sitting bout had ended later than usual.
These findings, together with data on interactions between the pair at the
afternoon exchange, suggest that the behavior of the sitting male reflects
an interval timing mechanism initiated with the onset of his sitting bout.
In contrast the attempts to regain the nest by the nonsitting female
probably reflect a circadian oscillation.
