Why do men have nipples, and how does the eye adapt to light?

We explore some of the curious questions that science can answer

How do our eyes adapt to light and dark? (Getty/iStock)

Men have nipples, but are they used for anything?

Men’s nipples certainly don’t serve any important physiological function, unlike the nipples of women; rather, they are a hangover from the early days in the womb.

The fundamental differences between boys and girls do not begin to become evident until between the tenth and fifteenth week after conception. Prior to this, males and females in the womb are anatomically identical.