When it comes to extramarital affairs, Tiger Woods may have raised the bar, but according to a new book on modern sexuality, the pro golfer may have been responding to a biological desire to "revive his staggering testosterone." In "Sex at Dawn: The Prehistoric Origins of Modern Sexuality" co-authors Cacilda Jetha and Christopher Ryan argue that men's testosterone levels begin to decline in their 20s, and one way they revive it is by meeting a new woman... Here's what you had to say: Tee commented via Facebook: "No one is programed to do anything. Folks cheat because they want to and feel they can get away with it." Cassandra wrote via Facebook: "I think the research maybe on to something, however, self control and self respect ought to still play a major role in a man's mind."