Chennai: A latest study has found male and female birds have an almost identical set of genes, but they function differently in each sex.
According to scientists from the University of Sheffield, males and females of the same bird species can be strikingly different.
For example, in addition to fundamental differences in reproduction, the sexes can show profound variation in behaviour, colouration, metabolism, disease incidence and life history. The team wanted to understand how these remarkable differences develop despite males and females sharing mostly the same DNA.
Published in Molecular Biology & Evolution, the study revealed hundreds of bird genes that use this method to enable the evolution of sex differences. The researchers showed that these genes have evolved remarkably rapidly as a result of the different selection pressures experienced by males and females.
“One notable example of differences between male and female birds is in the peafowl, peacocks have magnificent plumage, whereas the female peahen is relatively dull. The peacock’s long tail and bright colours evolved to help them attract mates, but having such eye-catching looks can come with negatives such as making them more noticeable to predators,” Thea Rogers, PhD student at the University of Sheffield and lead author of the study, said.
“Features like this are beneficial to the males but may not be beneficial for females, so birds must find a way to evolve different characteristics. We predicted that the secret to these differences must lie in understanding how the same genes are expressed and function differently in males and females,” it added.