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.
Awake when
Any time wonders
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.
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.