The geoduck clam's siphon is so large it cannot retract into its shell.

Sharks predate trees by about 90 million years — they've been swimming Earth's oceans for 450 million years.

Fact #5120 · Ocean

Some deep-sea fish like the viperfish have teeth so large they cannot close their mouths.

Fact #5109 · Ocean

The Pacific Ocean contains numerous coral atolls.

Fact #315 · Ocean

The ocean contains structures larger than mountain ranges.

Fact #2142 · Ocean

The tallest mountain from base to peak is Mauna Kea in Hawaii — it's just mostly underwater.

Fact #3405 · Ocean

Over 90% of Earth's volcanic activity occurs underwater, along mid-ocean ridges.

Fact #4774 · Ocean

The highest recorded ocean wave exceeded 80 feet in height.

Fact #920 · Ocean

Ancient oceans once covered much of Earth's surface.

Fact #705 · Ocean