A new study has revealed that male bird's brighter color and plumage could have been caused by their skills in searching for potential foods and hunting habits.

The study was conducted by team of researchers from University of Wisconsin-Milwaukee. A research team led by UW-Milwaukee biological sciences professors Peter Dunn and Linda Whittingham and Jessica Armenta of Austin Community College studied almost 1,000 different species of birds.

Armenta examined data from 977 species of birds for the past four years. She also paid visits to six museums in Australia and the United States at some point during the research. She concentrated on three females and three males of six species of birds.

To accelerate the study, Whittingham and Dunn scrutinized the data thoroughly. They provided each bird a color score hinged on the levels of brightness and shade. They also evaluated the plumage color in connection to ten scales of sexual and natural selection.

They found that although male birds do typically have brighter feathers compared to females, the gap between the two sexes is closing. This gap narrowed as both male and female birds evolved over time to merge into their surroundings and hide from predators.

The study authors said, "Although most studies of bird plumage focus on dichromatism, evolutionary change has most often led to similar, rather than different, plumage in males and females. Our study shows that ecology and behavior are driving the color of both sexes, and it is not due to sexual selection".

The researchers concluded that bird coloration was influenced by both natural selection and sexual selection. However, it worked different ways. The reproductive differences were caused by sexual selection while color changes in both sexes were caused natural selection. The study has been published in the academic journal Science Advances.