Penguins have excellent underwater vision.

Some butterflies migrate seasonally.

Sea lions can rotate their rear flippers forward to walk on land.

Public health sanitation reforms reduced disease outbreaks.

The Mariana Trench is so deep that Mount Everest could be placed inside it and still be covered by over a mile of water.

Dolphins can recognize themselves in mirrors.

The Earth's oceans are interconnected.

A giant squid lives in deep ocean waters.

Many deep-sea animals lack strong pigmentation.