LONDON: For female sparrows, infidelity comes with a cost -- the cheating
female's partner will provide less food for their nest of young, says a
Sparrows form pair bonds that are normally monogamous, but
many females are unfaithful to their partner and have offspring with
But male sparrows can judge if a spouse is prone to infidelity, the study found.
research showed that males cannot actually identify whether all the
chicks in their nest are theirs or not, and instead base their feeding
decisions on who their female partner is.
Also Read: 'Monsoon Journey': A Unique Homage To India's Rainy Season
"If chicks were
switched into a nest where the female was faithful, then the father at
that nest kept up his hard work providing for the chicks, suggesting
they have no mechanism, such as smell, to determine which chicks are
theirs," said lead researcher Julia Schroeder from Imperial College
"Instead, the males may use cues from the female's
behaviour during her fertile period -- for example how long she spends
away from the nest," Schroeder explained.
The study, published in
the journal The American Naturalist, followed the entire sparrow
population of the island of Lundy in the Bristol Channel in Britain for
Also Read: Drought In Telangana Hits Migratory Birds
The study followed 200 males and 194 females as they formed 313 unique monogamous pairs and hatched 863 broods on Lundy.
Some sparrow 'divorces' occurred -- but most changes of life partner were due to death.
team DNA genotyped every sparrow, allowing them to build up precise
family trees, and find out which females were most unfaithful and who
their cheating males were.
"Males changed their behaviour based
on their partner. When they switched from a faithful partner to one
prone to infidelity, they provided less food for their brood," Schroeder
The researchers believe that females might also change
their behaviour when paired with a less lazy male, cheating less with a
more attentive father.