Evolution: Cross-dressing hummingbirds.

The article informs on a paper published in the journal "Current Biology" by Jay Falk of the University of Washington, as per which some female hummingbirds have evolved to look like males. It mentions that he suggests it is a way for females to avoid being harassed when they are feeding, and plumage transvestism, known technically as female-limited polymorphism, is especially common in hummingbirds.