Are we born with full-sized eyeballs or brains? © Getty Images

Are we born with full-sized eyeballs or brains?

A newborn baby's head accounts for approximately a quarter of their body weight!

Asked by: Anonymous

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Babies are born with a lot more neurons than there are in an adult brain, but the brain itself weighs about a third as much. This is disproportionately large compared to the size of the body. It continues to grow until about age 18 as more connections are made between neurons.

The eyes are also about a third of their final size at birth, but they grow faster and at six months are already two-thirds of their adult size.


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