Do all animals have belly buttons?

Your navel is a wonder of nature that reminds you of where you came from

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Humans have belly buttons because before we are born we are connected to our mothers via an umbilical cord. This is a tube that delivers nourishment to the embryo (unborn baby), and removes its waste. It runs from the placenta – an organ in the mother’s body that provides a source of food and oxygen – to the tummy of the embryo. Once a baby is born, it can get nourishment, such as milk, through its mouth, so the umbilical cord is no longer needed. The cord shrivels up and drops off after a few weeks. Your belly button, also called a navel, is basically a scar from where the umbilical cord used to attach to your tummy.

Animals with placentas