The name ‘handicapped‘ is a bad-word in evolutionary biology because any phenotype which handicaps the organism gets eliminated in the long run. The handicap principle, as put by Zahavi and Zahavi, says that if an organism is strong and displays its strength to the predators risking his own life signaling that the predator would be wasting his time chasing the organism because the organism is strong enough to out-run him. So, the predator does not chase the organisms which exhibit their strengths and hence this trait survives in the prey’s population.
This theory, in my view, is flawed. First, there can be better ways of signaling (if it really occurs) the predator that one is strong without risking his life. Evolution, in the long run, would have found such ways. Second, why should there be any signaling from the predator to they prey at all. Even if the prey signals the predator, why does the predator believes it at all. I understand that in the long run if predators are not able to catch the prey because they are strong then (in the long run) they would not try chasing the prey that seems to be strong. But this is plain-jane natural selection. Who is handicapped here, the prey or predator? The answer is: no one. As mentioned earlier, a trait which handicaps the organism cannot be preserved in the population. There has to be some net-benefit for the organism from this seemingly handicap behavior. The theory should perhaps be called ‘seemingly’ handicap principle. Moreover, there is no need for this theory at all. Every thing the theory says is accounted by concepts of natural-selection and sexual selection. Why do we then need this theory?