Underwater rivers and lakes exist on the ocean floor, formed by dense brine that flows along the seabed.

Male seahorses carry and give birth to the young — the only male animal known to experience true pregnancy.

Fact #3527 · Ocean

Some seals can sleep underwater by surfacing periodically.

Fact #1290 · Ocean

Blue whales are the largest animals known to have ever lived.

Fact #246 · Ocean

Some deep-sea creatures produce their own light through bioluminescence.

Fact #1391 · Ocean

More than 70% of Earth's oxygen is produced by marine plants, primarily phytoplankton.

Fact #3399 · Ocean

There are deep ocean creatures that glow.

Fact #2292 · Ocean

Prehistoric oceans had different currents than today.

Fact #740 · Ocean

Male seahorses carry and give birth to their young.

Fact #359 · Ocean