What have you re-learned lately?

Day 278: One thing I learned today… Infants have 270-300 bones body, then as we mature, bones fuse together. On average, adults have 206 bones. Hands have 27 bones each Feet have 26 bones each This is probably something I have learned before however the body just amazes me. Is there something you have learned later in life (which you probably learned when you were younger) that really makes you think? Or just amazes you?