The pupil dilates in low light to let more in — and constricts in bright light to protect the retina.

Your brain controls your body.

Fact #2403 · Human Body

The human brain consumes roughly the same power as a small light bulb.

Fact #2456 · Human Body

Dogs' brains release oxytocin when they look at their owners, strengthening emotional bonds.

Fact #2521 · Human Body

There are more lifeforms living in your body than human cells.

Fact #2717 · Human Body

The human brain contains about 86 billion neurons.

Fact #1676 · Human Body

Your brain can store the equivalent of millions of gigabytes of information.

Fact #2124 · Human Body

Your senses are limited.

Fact #2377 · Human Body

The human eye can detect a candle flame over a mile away in darkness.

Fact #2633 · Human Body