Singing and building fancy nests to impress females are for ordinary birds. The male Costa's hummingbirds ( Calypte costae ) have gone not one but two steps higher to woo a mate – they perform high speed air diving and at the same time 'sing' with their tail feathers. They twist half of their tail vertically during the dive, fluttering the tail feathers to produce a tone.
Video source: University of California, Riverside
In a paper published recently in Current Biology , researchers at the University of California show that the male birds dive to the sides of the females and the style of the dive gives control over the acoustic frequency heard by the female. High-speed video recordings revealed that the side-way-dive also allows the male to look faster than they normally are.
“Recent studies in birds and other animals suggest that females prefer higher speeds during male athletic displays. By concealing their speed, males are not necessarily cheating, but instead have evolved this placement of trajectory out of female choice,” said Christopher Clark, assistant professor at the College of Natural and Agricultural Sciences and lead author of the study in a press release. “Most research has focused on static male attributes, such as bright colours or elongated tails, but our research shows that dynamic displays may be just as important, and males strategically control these performances to show themselves in the best possible light.”
