The first step in sexual selection
If Nature and natural selection had their way, there wouldn't be any men at all. That's because sex and mating are horribly inefficient ways of ensuring species survival compared to asexual reproduction in females.
So the question becomes, What are men good for, really?
The answer isn't sex but sexual selection or the process where the fittest and healthiest males win a mate. Sexual selection leads to populations that can survive longer in tough times and in maintaining the health of populations.
In sexual selection, healthier males tend to win over their rivals, spreading their genetic material more often. This results in better health for the species as a whole over time.
These were the findings of researchers at the University of East Anglia in the UK that conducted an experiment using flour beetles. The results of the experiment showed males do have a purpose -- ensuring competition for females that helps a species stay healthy.
"We wanted to understand how Darwinian selection can allow this widespread and seemingly wasteful reproductive system to persist, when a system where all individuals produce offspring without sex -- as in all-female asexual populations -- would be a far more effective route to reproduce greater numbers of offspring," said Professor Matt Gage of the University of East Anglia who led the study published in the journal Nature.
"Almost all multicellular species on earth reproduce using sex, but its existence isn't easy to explain. Sex carries big burdens, the most obvious of which is that only half of your offspring -- daughters -- will actually produce offspring. Why should any species waste all that effort on sons?
"Competition among males for reproduction provides a really important benefit, because it improves the genetic health of populations.
"Sexual selection achieves this by acting as a filter to remove harmful genetic mutations, helping populations to flourish and avoid extinction in the long-term".
Researchers found populations that experienced strong sexual selection maintained higher genetic fitness and were resilient to extinction in the face of inbreeding that can commonly occur when populations are put under pressure.
Populations that experienced weak or non-existent sexual selection showed far faster declines in health under inbreeding and went extinct within 10 generations.
Involved in the research were Alyson J. Lumley, Lukasz Michalczyk, James J. N. Kitson, Lewis G. Spurgin, Catriona A. Morrison, Joanne L. Godwin, Matthew E. Dickinson, Oliver Y. Martin, Brent C. Emerson, Tracey Chapman and Matthew J. G. Gage.
