Why do men have nipples?

Answer

Men and women are both human. They have a common build, with a few sex-linked variations. Both men and women inherit one copy from the woman and another from the man for all their genes. Both sexes therefore inherit genes for making breasts, and for breast hair. But, depending on their gender, those genes’ instructions are carried out differently. In the first few weeks, all fetuses look alike and have no sex yet. Only after a few weeks do they start producing sex hormones (testosterone for a man, estrogen for a woman). At that point, the breast tissue and nipples are already formed. Male hormones ensure that it stays there, female hormones ensure that they continue to grow. If, for some reason, that production of male hormones does not kick in, the fetus continues to develop into the female form, even though the child is genetically male. So you can say that the standard model for a person is a woman, even though the writers of the bible thought the other way around. (info: www.technopolis.be)

Thus, the origin of the nipples can be found at the beginning of life. During the development of an embryo, the female model is followed, i.e. with nipples. After about six weeks, hormones cause the male or female sex to develop. So the men have nipples and they have breast tissue left over from that early period.

In evolution, beneficial properties in the living environment of the organism are stimulated, adverse properties are eliminated, but evolution does nothing with neutral properties. As long as they don’t disturb, they stay put and that’s how it went with the man’s nipples.