Introduction
As with almost all questions of human anatomy about the “why”, the answer to the question “Why do men have nipples?” lies in embryology, i.e. the biology that deals with the development of the – translated – unborn foetus. That is, with the life that has not yet been born.
Declaration
The reason for the presence of the nipples in women is relatively simple: the nipple, as it is also called, is the name for the orifice of the mammary glands, at least in higher mammals. Moreover, it corresponds to the so-called teats in all other mammals. Men also have nipples, although strictly speaking these do not perform any function, because men cannot breastfeed children.
The answer to the question why they are present nevertheless lies to a large extent in our chromosome set. This is the term for the totality of all chromosomes of a cell. Chromosomes consist of DNA, the genetic blueprint that contains all genetic information about our later development and life.
These chromosomes are passed on to the next generation in the form of maternal eggs and paternal sperm. However, this fusion does not happen from one day to the next. In this case, nature is more complex than it appears at first glance.
It takes about 10 weeks for the new set of chromosomes of the unborn child to be fully developed. Until then, an embryo develops which, in fact, does not yet show the physical signs of a sex. Thus, at the very beginning of development, there is no visible difference between male and female embryos.
The information of the sex is anchored in the so-called gonosomes, the sex chromosomes. The male chromosomes look like a Y and are therefore called Y chromosomes, whereas the female chromosomes look like an X and are therefore called X chromosomes. Due to the presence of a Y chromosome, the body of the embryo becomes a male body, which produces testosterone, among other things, which causes, among other things, the voice to become deep, the testicles and other sexual characteristics to be developed.
In addition, this hormone later prevents the formation of a milk-producing (lactating) mammary gland. A mammary gland is embryologically but nevertheless present, even if it is not functional in the sense of milk production. The reasons for the presence of a mammary gland in men have not yet been conclusively clarified, but it may be assumed that it is probably more sensible for the human body to first apply all the characteristics of both sexes to the embryo before hormonal differentiation with the sex hormones begins. In addition, the man does not suffer any limitations from the presence of nipples, neither from a health nor from any other point of view. Therefore, it can be assumed that the nipples in men will continue to be applied to the embryo.
