In sport, the sexes are separate. Women and men do not run or swim in the same races. Women are less strong than men. That at least is why people say. Women are called "the weaker sex", or if men want to please them, the "fair sex". But boys and girls are taught together at schools and universities. There are women who are famous Prime Ministers, scientists, and writers. And women live longer than men. A European woman can expect to live until the age of 74, a man only until he is 68. Are women's bodies really weaker? The fastest men can run a mile in under minutes. The best women need 4.5 minutes. Women's times are always slower than men's, but some facts are surprised. Some of them swam 400 meters in 4 minutes 21.2 seconds when she was only 16. The first "Tarzan" in films was an Olympic swimmer, Johnny Weissmuller. His fastest 400 meters was 4 minutes 59.1 seconds, slower than a girl 50 years later! This does not mean.that women are catching men up. Conditions are very different now, and sport is much more serious. It is so serious that some athletes are given hormone injections. At the Olympics, a doctor has to check whether the women athletes are really women or not. It seems to say that sport has such problems. Life can be very completed when there are two separate sexes.