Natural selection, or the process whereby biological traits are kept in or weeded out of the gene pool, has been thought to be responsible for things like getting rid of tails and standing upright on two feet - and ultimately for keeping humans and other species alive and well. The results of studies in Israel and France now suggest that natural selection also favors musical ability in men, according to Pacific Standard. In the French study, conducted at the University of South Brittany and published in the journal Psychology of Music, an actor approached women he saw on the street, told him he thought they were "really pretty" and asked for their phone numbers. When the actor approached the women while carrying a guitar case, 31 percent gave him their phone numbers. Only 9 percent of the women gave him their numbers when he approached carrying a sports bag, and 14 percent when he approached carrying nothing at all. In the Israeli study, 100 women college students received a man's Facebook profile containing his photo, a message from him saying "I like your photo" and a friend request. Half the women received photos of the man playing a guitar, the other half received a photo of the man without the instrument. Twenty Eight percent of the women who received the photo with the guitar responded positively to the friend request, compared with only 10 percent who accepted the friend invitation after receiving the photo without the guitar. Based on the results of their study, the French researchers hypothesize that playing music might be associated with "physical and intellectual abilities," and that it might call forth desirable impressions of the wealth and status of musical stars. But while the French and Israeli studies suggest that musical ability in men increases their attractiveness to women, it doesn't seem to work the other way around. Another study by the French researchers suggests that musical ability in women doesn't increase their attractiveness to men. Read more: The Mating Advantage of Male Musicians (PS)