Why do we have belly buttons?

Everyone has an umbilical cord as they are developing in the womb.

When a fetus floats inside a mother’s womb, its belly button looks more like a buttonhole than a button. The hole connects a fetus to an umbilical cord. The cord funnels nutrients, vitamins, minerals, and oxygen from the mother to the fetus. It also carries waste away from the fetus.

Once a baby is born, it no longer needs to be attached to its mother with a tube so a doctor will snip off the umbilical cord, leaving behind a small stump. After a few days, the stump dries and falls off. What’s left is an innie or an outtie. Now, the baby can breathe, feed, and make dirty diapers all on its own.

The belly button is just the scar from where the umbilical cord is detached at birth.