Manser, Marta B.; Madden, Joah R.; Kunc, Hansjoerg P.; English, Sinead; Clutton-Brock, Tim H.
(Elsevier, 2008-07)
In many bird species with biparental care for young in the nest, hungry chicks beg repeatedly and parents adjust their feeding rate to the call rate of young. Repetitive calling also occurs in fledglings and in some mammals ...