Learn what women do nearly twice as much as men.
One of the many differences between men and women is in facial movement: Women typically make movements, such as blinking, tilting and nodding, more frequently than men. Blinking in particular can be twice as frequent in women as in men.
Why do we blink at all? Blinking ensures the constant lubrication of the eyeballs and protects them from foreign objects. It also clears the eyes of tear fluid, pushing any excess into the ‘puncta' (tear ducts) at the inner corners of the eyelids.
Women blink more often than men essentially because of the higher levels of Estrogen in their systems. Estrogen as a hormone stimulates the production of lubricants throughout the body, including the eye.
Women on birth control pills (or estrogen supplements) who have elevated levels of estrogen blink even more frequently -- up to 32 percent more often -- than other women. Similarly, post-menopausal women often suffer from "dry eye."
Maybe that's why "batting one's eyelashes" is so universally perceived to be flirtatious: blinking and fertility are hormonally connected.
It might stand to reason that all that blinking might stimulate additional eyelash growth but when it comes to eyelashes, men typically have longer lashes than women.