Birds of a feather mob together
(PHYSorg.com Biology)

Dive bombing a much larger bird isn`t just a courageous act by often smaller bird species to keep predators at bay. It also gives male birds the chance to show off their physical qualities in order to impress females. This is according to a study in Springer`s journal Behavioral Ecology and Sociobiology on predator mobbing behavior of birds where potential prey approach and harass would-be predators such as owls. The study was led by Filipe Cunha of the University of Zurich in Switzerland and the Federal University of Ouro Preto in Brazil.