Blue whales can grow longer than 90 feet.

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

There is a river in the ocean — the Gulf Stream moves more water than all of Earth's rivers combined.

The anglerfish uses a bioluminescent lure to attract prey in the dark ocean depths.

The immortal jellyfish is the only known animal capable of reverting to its juvenile form repeatedly.

Some coral reefs are visible from space.

In 1796, Edward Jenner developed the world's first vaccine by using cowpox material to induce immunity against smallpox, a breakthrough that led to the disease's global eradication.

Dogs can smell certain diseases such as cancer.

Some whales communicate across vast distances underwater.