A new insect study finds that females influence the gender of their offspring so they inherit either their mother's or grandfather's qualities, showing for the first time that females can manipulate the sex of their young.

Scientists at the University of Exeter, UK, Okayama University and Kyushu University, Japan found that “high-quality” females, those which produce more offspring, are more likely to have daughters while, weaker females, whose own fathers were stronger and more successful, produce more sons.

While the study only focused on the broad-horned flour beetle, Gnatocerus cornutus, the team believes the findings could apply to other species across the animal kingdom, even mammals.

The authors explained that poor-quality females produce more sons who inherit their grandfather's good qualities while, high-quality daughters, fathered by poor males, produce relatively small-jawed and weak sons, and compensate by producing more female offspring that will inherit their mother's good attributes.

"Our study shows females are able to bias the sex ratio of their offspring in surprising and subtle ways. These findings shed new light on why some families have lots of sons, while others have mainly daughters. Of course everyone will be interested to know if the study can help explain why this sometimes happens in human families but I'm afraid we can't answer that," said Dr David Hosken of the University of Exeter.