Although colorful, the male is still a simple creature

Why do the males of the species evolve faster than their mate? The mystery comes from this: Men are simpler creatures.

In most species, males seem to always produce brighter wings, more glamorous dances and more melodious songs in fights to get a mate. The result of this so-called breeding reproduction creates a flashy male and a rustic female. It seems that evolution has been pushed faster in males than females.

The idea of ​​this was born in the 19th century, when Charles Darwin observed the majestic male tail tails compared to the creased tail of the gray work. Why and how males do it, are still mysterious to scientists.

Recent research in fruit flies has found that, in males, the number of genes that prevent them respond quickly to external pressure is much less than that of females. " It's because of the simpler guys ," said lead researcher Marta Wayne, a zoologist at Gainesville University in Florida, USA.

"Genetic methods in males involve a simpler genetic structure, not as much genetic interaction as with female genetics." The finding may also explain why disease manifests differently in women and men.

The researchers found that males can respond faster than females in breeding selection, creating more colorful wings.(Photo: LiveScience)

The solution is in the gene

In the experiment, people studied fruit flies, which had identical genomes, except sex chromosomes.

In fruit flies (as well as humans) the genome is packed in pairs of chromosomes, including sex chromosomes. In females, the sex chromosome pair is XX, while the male is XY. While the number of genes on the X chromosome is numerous, on the contrary, only a few genes are associated with the Y chromosome. Each gene usually has two versions, called alleles. In fruit flies, these alleles interact with each other and with other genes.

Since males have only one X chromosome, " what you see is exactly what you expect ". If a gene helps him increase his mating ability, that gene will be selected to go further, and vice versa, if a gene is not good, it will be eliminated after only a few generations. But in females, the tangled interaction between genes on two X chromosomes and between alleles in each X makes it more difficult to select and pass on good traits.

"Having only one X makes the genes of the male more openly selected."

The researchers note that this result is not directly related to people, because "the function of X on other people is in the fruit fly". However, it also helps explain the difference between the rhythm and the response to the disease of men and women.

Thuan An