Why do people have extra nipples?

Extra nipples were once thought to be a link to our evolutionary past, but the truth is a lot stranger, writes Jason G Goldman.

Third (supernumerary) nipple: Types, causes, and removal

One In 18 People Are Born With Third Nipples - Why?

Extra nipples, called supernumerary nipples, is more common than

Puffy Nipples - Causes, Symptoms and Treatments

Is it okay that I have one nipple more puffy than the other, and is it bad that it hurts when it hits something? - Quora

The Surgical Treatment of Bilateral Supernumerary Nipples

What Does Having a Third Nipple Mean? Supernumerary Nipples - GoodRx

From Paris to Pennsylvania: A Summer of Long Distance, Love, and Journals

I have 4 extra nipples located on my stomach and I really don't

Third Nipple (Supernumerary Nipple): Causes, Types & Removal

Ron Paul Forums / Liberty Forest

From Paris to Pennsylvania: A Summer of Long Distance, Love, and Journals