While I am sure many will say the obvious answer is males, I would argue they are not.
Men do run things on the surface and are stronger and faster in general.
Not only have men always feared women, even rulers, women often run things behind the scenes and put ideas into the men's heads. In today's world, and in the past the women bore the weight of the children, and when the man is not around had to do all of the things a man would do and take care of the children. How many single mothers are out there? Some men can do some of that, but no matter what they can't have the children in the first place and most never would even if they could, most would even tell you as much.
As mentioned by Miniar, many species are female dominated on an underlying level. They only allow the men to be in control.
Women bear the weight of the world, the men just live in it and think they control it. 😀