Feminists have debated it for decades, but scientists have finally got to the bottom of why men still exist.
Biologists have always puzzled over why males have survived given that their only contribution to reproduction is sperm.
It makes far more sense in evolutionary terms to have an all-female asexual population which creates daughters who can reproduce rather than sons who cannot, such as the Mexican whiptail lizard.
But new research suggests that sexual competition for mates keeps populations healthy, free of disease and genetically diverse.
“Almost all multicellular species on earth reproduce using sex, but its existence isn’t easy to explain because sex carries big burdens, the most obvious of which is that only half of your offspring – daughters – will actually produce offspring,” said lead researcher Prof Matt Gage, from the University of East Anglia School of Biological Sciences.
“Why should any species waste all that effort on sons? An all-female asexual population would be a far more effective route to reproduce greater numbers of offspring.
“Our research shows that competition among males for reproduction provides a really important benefit, because it improves the genetic health of populations.”