Defence against predators
Deflect or distract the attack. Many offer a non-essential part of the body, for example, butterflies whose wings have small 'targets' near the edges. Cuttlefish squirt out a cloud of black ink, turn pale and swim fast away from the ink. The Kentish plover, which lays its eggs on the ground, lures attackers away from the eggs. It uses a remarkable impression of being damaged with a broken wing. When the predator is well away from the eggs, the bird flies off.p175 Other plovers sit on imaginary nest sites: both methods are distraction displays. Quite a number of animals can break off a non-essential part of their body, and may regenerate it later.p179