I'm confused about something. I've known that many species have the characteristic that the males try to eat the young for some time now. I even understand how this may have evolved, and it doesn't seem unlikely. But, what I just can't get is, how did these species survive? For that matter, how does this tendency survive, since the tendency is a self-destructive one (on the level of species obviously, not on the level of individuals)? Any help is appreciated.