A scientist in Israel, Shani Gelstein, began collecting women’s emotional tears in vials. Gelstein wanted to know why people cry at emotional moments and believes them to be a chemical signal. In a couple different tests, she looked at how female tears affect males. She had men smell saline drops and tears and watched how their brain reacted.
The parts of the brain that deal with sexual desire notably dropped after sniffing the female tears. Men had no reaction after smelling the saline, though. They also tended to find women less attractive after smelling the female tears. Gelstein believes that tears are a way of getting rid of extra chemicals in our body that build up.
That is why we feel better or relieved after a good, emotional cry. It also marks a person as more submissive. They can help trigger sympathy from friends or mercy from an enemy. It is possible that they even make men less aggressive.