Probably the energetics.
When the body develops, women actually begin as more yang. The activities from the central channel begin sooner and cause the body to develop. When men are developing, the activities from the central channel begin at a later time.
This causes the defining energies for women to begin at the top and to descend. For men, they begin at the bottom and rise. --This creates a defining pattern for the development of the body and the aura layers.
When the energy fields interact, the complementary opposites cause an increase in kinetics due to an ease of flows. If either a man or woman were alone, the defining polarity would be their own against a fairly neutral backdrop. But, males and females in proximity will have complementary positioned anode and cathode centers for the energetics. --This is perceptible even through images due to the holographic qualities of information in an energy fieldā¦ I wish I had a better description for it, but it is what it is.
So, in that sense, men respond to women precisely because they are women 
