(In reply to Corporal Hicks)
Not only that, but the females can be twice the size, they can have different skin coloration, ect. Also, since Predators walk upright, they would need large hips to allow a child to pass out the birth canal, so hips are another secondary sexual characteristic to point out. I can pick out between a male peacock and a female peacock just fine without anyone having breasts into the equation.
Though personally in my headcanon (TM) I believe females would have some kind of breast growth toward the end of gestation and after their offspring are born. As I believe Predators are proto-mammals and are warmblooded. They have obvious higher intelligence and have a large brain case, both which point very highly to warmbloodedness.
