Story
A tooth that senses the sea
The Unicorn of the Sea
A narwhal's long, spiraled tusk isn't a horn at all — it's actually a giant tooth, longer than a grown-up is tall, packed with nerve endings that can sense the water around it.
Size
Car-sized wonders
Story
One eye on watch
The Dolphin's Half-Awake Sleep
A dolphin sleeps with only half of its brain at a time, keeping one eye open to watch for danger.
Story
Memory keeper
Wise Elephant
The oldest elephant in a herd remembers the way to water holes that only she has ever visited.
Story
Hidden warmth
The Bear's Black Skin
Under all that white fur, a polar bear's skin is actually jet black.
Story
Standing dreamer
Giraffe Catnap
A giraffe may sleep for only a few minutes at a time, adding up to less than an hour of rest a day.