Why do men have nipples?. It’s the kind of question that doesn’t need to be answered but should be interesting to find out why they are there. It’s understandable for women to have nipples because it is the distributor for the breast milk to feed a newborn baby but a man, what does he need it for? According to Darwin’s theory on natural selection, it is theorized that men shouldn’t have nipples because during natural selection, the undesirable traits in the male/female body gradually lose their parts they don’t need over time. This would make sense as to why men have nipples; the process must not go through natural selection obviously since there must be a significant reason for it being there. A great example was the appendix, which now a useless part of our bodies was a part of the digestive track making it significant component. 
Men have nipples because it follows part of a female template since both sexes have similar tissue and body parts. Since this is confirmed that we share parts, it isn’t hard to understand why men just have nipples. When breasts grow abnormally on men it is called gynecomastia, which is the enlargement of breasts. So the question is simple surprisingly, Men and women follow the same template and nipples are just created no matter what sex you are and the chromosomes figure out if they will be functioning or non functioning in the process of knowing if they are going to be a man or woman. Its the effect of genes, in which the Y chromosome and hormone testosterone that changes the embryo. The idea of shared genetic basis of two traits is known as genetic correlation. Genetic correlation is “the proportion of variance that two traits share due to genetic causes.” The evolutionary default is for males and females to share characters through genetic correlations. Testosterone promotes the growth of the penis and testicles in men and since nipples are there before this process begins, they inhabit. Some genetic scientists have noted through this article that if nipples were harmful for the male body, they would have disappeared over time.