How Many Bones Are In A Newborn Versus An Adult?

This is the biggest reason for the discrepancy in bone count.

• Newborns: A baby is born with approximately 300 bones. This high number isn't because they have "extra" bones, but because many of what will become single adult bones are still in several, separate pieces.
• Adults: An adult has 206 bones.

The change from 300 to 206 is due to a natural process called ossification (the process of new bone formation) and bone fusion. A newborn's skeleton is largely made of flexible cartilage, which allows for a safe passage through the birth canal and rapid growth.

As the child grows, this cartilage is gradually replaced by hard bone, and many of these smaller bones join together.For example, the "soft spots" (or fontanelles) on a baby's skull are gaps between cranial bones that will eventually fuse solid.