Battle Of The Sexes Benefits Offspring, Says Research In Birds

In nature, it is quite rare for both parents to be involved in raising young, but it is very common in birds, some fish and primates including humans. Researchers therefore wanted to find out why, for some animals, parents stick together. [...]

Dr Harrison explained: “Caring for offspring is essential for their survival in many species, but it is also very costly in time and effort. Time spent bringing up your young means lost opportunities for remating and having more offspring, so parents face a trade-off between caring for current offspring and creating future offspring.

“This creates a conflict of interest between parents, since each parent would benefit by leaving their partner holding the baby whilst they go off and start a new brood elsewhere.

“This is exactly what happens in most animal species, so we wanted to understand how and why animals like birds and primates have evolved the tendency to share their parental duties.”

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