Amotz Zahavi is an Israeli evolutionary biologist from Tel-Aviv University, and one of the founders of the Israeli Society for the Protection of Nature.
He is best known for his Handicap theory, first published in 1975, which explains the evolution of characteristics, behaviors or structures that appear to reduce fitness and endanger the organism. The explanation is that these characteristics evolved by sexual selection as a signal of fitness, to attract potential mates.
For example, the tail of a peacock makes the peacock more vulnerable to predators, and is therefore a handicap. But the message that the tail carries to the potential mate peahen is 'I have survived in spite of this huge tail, hence I am fitter and more attractive than others'.
