Handicap principle
The handicap principle was invented by Prof. Amotz Zahavi from Tel Aviv University. It claims to explain the fact that some animals have characteristics that do not necessarily help them survive. Lets take the peacock for example. The peacock's tail is long and heavy and actually diminishes its chances to survive. So why did it evolutionary survive?According to the principle, one day, a female peacock liked longer tail, and looked for a male with this characteristic. the mature mail she found was strong enough to survive even though it had a long tail and therefore it is probably stronger than the average peacock. therefore, its predecessors are going to be stronger, and also to have a long tail.
This principle comes in addition to the well known evolution theory claims that only the one that fits best to its environment survives.