London, Dec. 6: Intelligent men produce better quality sperm, British researchers have demonstrated.

Research has suggested that in our ancestors intelligence and sperm quality were linked so clever men were more likely to reproduce.

It is thought that the genes that are linked to intelligence also have a role to play in sperm quality, even if the effect is only small.

But experts said that if couples are having problems conceiving it does not mean the man is not intelligent or that training your brain will improve your chances of becoming a father. In modern society, intelligent men actually tend to father fewer children through greater use of contraception and marrying later.

A team at King's College London were testing a theory that single genes can affect a wide range of characteristics that are seemingly unrelated. Rosalind Arden, lead author, said: “As an initial proof-of-concept, we took two characteristics that seemed, on the surface, unlikely to be associated with each other — intelligence and sperm quality — and tested whether there was a statistical relationship between them. “We found a small positive relationship: brighter men had better sperm. But we are not trying to say that under modern conditions intelligent men are going to have more children.

“We wanted to test the idea that intelligence is favoured by natural selection.”

The effect remained after factors, such as intelligent men being less likely to smoke and more likely to exercise more, were taken into account. The research is published in the Journal Intelligence.

Allan Pacey, senior lecturer in Andrology, University of Sheffield, said: “The fact that it’s possible to detect a statistical relationship between intelligence and semen quality in adult men probably says more about the co-development of brain and testicles when the man was in his mother’s womb, and, therefore, how well they both function in adult life, rather than suggesting that playing Sudoku can somehow stimulate more sperm to be produced.

“The improvement in semen quality with intelligence observed in this paper is small and therefore it is unlikely to have a big impact on the ability of men of different intelligences to conceive.”