Male Nipples

The last vestigial features we have on this list - male nipples - are most likely vestigial in a different way in the sense that they aren't left over from an evolutionary event, but rather an embryological/developmental one. To be more specific, men have nipples because of the development process that they go through in their mother's womb.

In reality, all fetuses start off in the womb as females. The embryo will mature into a full-fledged female if there is no fetal Y-chromosome present. On the other hand, when a Y-chromosome is present, the fetus will create hormones like testosterone and develop into a man, but the nipples will essentially just hang out. As a result, they are purely ornamental. In short, guys have nipples because they evolve early on in the womb and at that point, it is still up in the air as to whether or not the baby will be male or female.

There are some cases where males can lactate from time to time, however, the biological function of male nipples is still unclear. But it is in fact undeniable that nipples are simply a part of the human body that if someone is lacking it, they wouldn't look as "natural" as others.