Female red junglefowl select most diverse genes

New collaborative research has suggested that female red junglefowl have an internal mechanism that results in healthier offspring with better disease resistance.

The study into red junglefowl, the wild ancestor of the domestic chicken, revealed that the reproductive tract in females favours sperm from males that are most genetically different to them.

This mechanism enables females to maximise the genetic quality of their offspring by mating with a number of different males.

In doing so, females increase the diversity of the Major Histocompatability Complex genes (MHC) in their offspring, which are key to detecting and fighting infections.

The study, which was carried out by researchers at the Universities of East Anglia (UEA), Oxford, Stockholm and Linköping, shows that multiple matings produce the most disease-resistant and genetically healthy offspring in this species.

"Our research has shown that the females don't need to choose between males to produce the most healthy offspring," explained Professor David Richardson from the UEA's School of Biological Sciences.

"Rather, by mating with multiple males, they allow their internal choice mechanism to favour the most genetically different sperm."

Prof Richardson added that this could be the case in other animals, including humans – though testing would be unethical in this instance.

In addition, the researchers found that the internal mechanism was not effective during artificial insemination, indicating that subconscious assessment of the male is needed by the female during mating.

"Having correct cues during mating – perhaps the smell of the male – can affect a female's chances of being fertilised… this is something that needs to be explored further," concluded Richardson.

The study has been published in the Proceedings of the Royal Society B journal.