An adult human has exactly 206 bones. Babies, however, have as many as 300. When they’re born, a lot of what will eventually harden and fuse into solid bones are individual pieces of soft bones, or cartilage.
But some bones adults have that newborn babies don’t have: knees. Those remain soft cartilage until well after birth. Why? They absorb impact as the baby learns to crawl, stand-up, and walk…and they fall down a lot in the process.
Most of a baby’s senses are well developed by the time they’re born. The exception: taste. Specifically, until they’re about four months old, babies lack the ability to taste salt.
What’s the one thing babies do better than anything else? (Okay, besides fill diapers and sleep.) They cry. But while they shriek and wail, their eyes don’t dispense actual water droplets. Tear ducts don’t do anything until a baby is, on average, about six weeks old.
Babies develop in the womb of a pregnant woman…which means there are a lot of hormones floating around. They’re exposed to high levels of estrogen that when the stream is cut off upon birth, that shift can trigger a reaction called galactorrhea. In other words, baby girls and baby boys may temporarily lactate.
Babies in the womb consume food and liquid from their mom, which means they also produce waste. That pee doesn’t have anywhere to go but into the amniotic fluid that surrounds the baby. Long story short, the baby winds up consuming it…starting the process all over again.
Developing infants are kept warm in that fluid with a fine layer of fur called lanugo. It usually dissipates in the days before the baby is born, but not always, resulting in the occasionally slightly furry baby.