Reason For Peacock’s Colorful Tail
Even Charles Darwin struggled to explain why the bird should have this burdensome trait. When there are many potential danger related to the colourful tail, why this bird got this trait. Darwin finally got the idea of sexual selection, which provides an advantage in the competition for mates and that outweighed other disadvantages. While humans are attracted to symmetrical faces and other outward signs of fitness, these birds are attracted to colourful tails. The male specific traits are evolved with the changing preferences of females. When the female tastes change, these traits go away.
Image credit : http://blog.oregonlive.com
Ultrasonic for Sex
Chinese tree frogs have developed unique, high-frequency vocal skills to make themselves heard by potential mates in their noisy habitat. The noises are mainly courtship calls. Males make these noises to advertise their virility, and females squeak to announce their fertility. These frogs produce their calls in ultrasound, which has shorter wavelengths than audible sound. They compare the intensity of the sound signals received by their two ears to to find where the sound is coming from.
(Photo Source:flickr.com/photos/65273942@N00/334330113/)
