Ageing neutralises sex differences in the brain, suggests study

A team of researchers from Linkoping University suggested that male and female fruit flies’ brains become desexualized as they age. Both sexes endure age-related changes, however, the male brain gets more feminised than the female brain becomes masculine. The findings of the study were published in the journal - 'Proceedings of the Royal Society of London B'. Weaker individuals cannot afford to “invest” in sexual behaviours to the same degree as their healthier conspecifics, which is a well-known fact. It is unclear, though, whether ageing, which weakens people, also causes a decrease in interest in sexual activities. Going "all in" on reproduction might seem like the best option for people who are nearing the end of their lives in order to pass on their genes before it's too late. The brain controls sexual behaviour, so researchers looked at how the expression of specific genes changes with age in young males and females to learn what happens to sex differences in this tissue in fruit flies. The study demonstrates that a gene's expression is reduced in older females and increased in old males if the gene's expression is higher in the brains of young females than in young males, and vice versa for genes with higher expression in young males.