Sure, all babies are cute, but that doesn't mean they aren't also extremely weird. Babies are eating, sleeping and pooping machines that double their weight in their first few months of life. And they pack a whole lot of oddness in while they're at it.
Here are 10 ways babies are much weirder than adults.
1. Babies grow mustaches in the womb. And then eat them.
During the second trimester of pregnancy, all babies (boys and girls alike) grow fine hair on their upper lips that then spreads to the rest of their bodies. In most cases, University of Sydney anthropologist Stephen Juan tells The Register, this hair — called lanugo — falls out before the baby is born and is reabsorbed (or eaten) by the baby in the womb.
2. Babies don't have kneecaps, sorta.
Have you ever noticed how flexible a baby is? This is partially because babies have soft, supple bones and large sections of cartilage. A newborn baby's patella (kneecap) is made almost entirely of cartilage, says Healthline. As they get older, areas of hard bone start to form, eventually hardening into a kneecap around age 10-12.
3. Babies have more bones than adults.
You might think that their little bodies would house fewer bones than adults. But babies are actually born with around 300 bones, whereas adults only have 206, reports KidsHealth. As time goes by, some of those bones ossify or fuse with others to create bigger bones, particularly in the spine and skull.
4. Newborn babies don't shed tears.
Sure they shriek. They wail. And they can kick up a good fuss. But newborn babies don't shed tears. Babies are born with tear ducts, but they aren't fully developed yet, so they don't yet produce enough extra fluid to do anything more than lubricate the eye, pediatrician Vincent Iannelli tells Parents. Those big, fat baby tears don't come along until the baby is a few weeks — or even a few months — old.
5. Newborn babies hardly sweat.
A newborn also tends to have dry skin because a baby's sweat glands aren't fully working yet. Because newborn bodies are still developing sweat glands and their own heating/cooling systems, it's important for parents to keep them cool and make sure they don't get overheated. Not long after birth when sweat glands kick in, some parents worry that babies are sweating too much, especially when eating or sleeping. "Both actions are tough work," Katie Ellgass, a
pediatrician at Stanford Children's Health Altos Pediatric Associates in Los Altos, California, told Live Science. "When feeding, a baby is often close to their caregiver, so body heat is transferring. It's a sweatfest!"
6. Babies develop a sense of taste before they're born.
Even in the womb, babies start developing a sense of taste. During the first two weeks of pregnancy, taste buds start forming where a baby's tongue will be, reports What to Expect. These receptors will eventually allow them to recognize flavors — sweet, sour, bitter and even umami, a recently identified taste associated with hearty, savory foods like meats and mushrooms. What a pregnant mother tastes, her baby tastes too.
7. But they can't taste salt.
One taste they can't sense? Salt. Research published in the journal Developmental Psychobiology suggests that newborns cannot taste saltiness until they are about 4 months old.
8. Newborns prefer to turn to the right.
Researchers aren't sure why, but a study published in the journal Science shows that the majority of babies (about 65%) prefer to turn their heads to the right. And the preference may be connect to right-handedness later in life.
9. Babies can breathe and swallow — at the same time.
Adults can breathe or they can eat, but they certainly can't do both. But babies can! From birth through the first few months of life, babies can breathe and swallow simultaneously, reports Live Science. That definitely comes in handy during those marathon nursing sessions.
10. All babies develop amnesia.
In a phenomenon known as "infantile amnesia," babies forget most of their first three years of life. Neuroscientists think this might be because the sections of the brain that record memory are not fully developed for a baby's first few years. Either way, it's the reason that most of us can't remember those carefree kneecap-less, mustache-eating days of childhood.
Editor's note: This story has been updated with new information since it was published in January 2016.