Look at these two faces that we present to you.
Which of them corresponds to a man and which to a woman?
Most of us answer that the woman corresponds to the face that appears on the left and the face of the man is what we see on the right. Nevertheless, Both faces are the same. A simple change in the contrast of the image makes us perceive it as a man or woman even when it is the same face.
The face with the highest contrast, the one on the left, is perceived as feminine while the face with the lowest contrast, the one on the right, is perceived as masculine.