Lady nightingales have an easy way to determine whether a prospective partner will make a doting father: Can he sing? Male nightingales convey their strengths as a future parent through song, according to a new study in the journal BMC Evolutionary Biology.
A group of German zoologists found in observing nightingales that males who are better singers are also more doting fathers, indicating that females might look for superior crooners while choosing a mate.
Nightingales are monogamous, living together in pairs and sharing resources. Male nightingales defend the nest and feed their mates while their partners sit on the eggs, and fetch food for their offspring once they hatch. The birds have large singing repertoires—males can exhibit up to 180 different song types each—and they sing these song types in specific orders that scientists hypothesize convey certain information to a prospective mate.
Not all nightingale dads are attentive to their children. Certain aspects of the male nightgales’ songs predicted how often the bird would return to the nest to feed his chicks. Birds that sang many different types of trills and whistles and sang their songs in a more orderly fashion, repeating the same sequence of song types over and over, tended to be better fathers. The males used their singing prowess to advertise their fatherly skills before they paired up with a female, though the experiment did not examine whether the female birds choose great singers as mates over less talented males.
This is the first study to demonstrate a relationship between the sequence of a bird song and the quality of paternal care, although other researchers have found associations between the complexity of bird song and higher feeding rates. For birds, at least, rock stars make awesome dads.
[h/t: Scientific American]