My high school class was studying natural selection, and we were discussing various strategies employed by different animals to attract mates and produce offspring. I was describing how some animals will stay near the female after mating to ensure that no other males mate with the female. In at least one species of bee, the male breaks off his genitalia inside the female to prevent other males from inseminating the female. Of course, he then dies. This thought had an immediate effect on all of the males in my classroom. After a few seconds of total silence, one boy in the back said, "Now THAT'S commitment!"