Water is the only natural substance that commonly exists as a solid, liquid, and gas on Earth.

The pacemaker regulates irregular heartbeats.

Fact #1581 · Human Body

Mammoths and early humans lived at the same time.

Fact #633 · Human Body

Border collies can learn hundreds of word-object associations.

Fact #1303 · Human Body

Fossils are formed when remains are preserved in rock over millions of years.

Fact #631 · Human Body

The first successful heart transplant was performed in 1967.

Fact #1014 · Human Body

Some insects can lift many times their body weight.

Fact #213 · Human Body

Cats can rotate their ears independently.

Fact #1336 · Human Body

Learning involves changes in neural connections.

Fact #986 · Human Body