Females want males with the longest tail feathers. Red feathered males want to swirl and strut over larger domains. Descending from dinosaurs was no simple task for birds, and they haven't stopped today in fantastically adapting to get what they want.

Since Darwin's time, scientists have struggled to explain how the diversity of birds' plumage was possible. At the Department of Zoology at the University of Gothenburg, a keystone in this erection of knowledge was penned in 1982 by a history making Swedish researcher at the University of Gothenburg, Professor Malte Andersson, who wrote "Sexual Selection." This showed how animals use behavioral signals, colors and other ornamentation to compete for a mate.

Now, researchers at the same university studying the same foul - African widow birds and red bishops - have added knowledge to his work by showing that these birds became partly red, although they were originally yellow.

Researcher Maria Prager discovered that today's species descend from birds with short tails and yellow colors. The current red color has evolved by birds storing yellow dietary pigments in their feathers, and this produces a red hue. Alternatively, they have converted some of the dietary yellow pigment to red with the aid of an enzyme.

Prager's hypothesis entails that the color and feather signals of widow birds and bishops have become increasingly more extreme during evolution. "Our combined research provides a unique and complete picture of color evolution in birds," remarks Prager.

Source: University of Gothenburg