Gift economies — where goods are given without explicit agreement of repayment — were dominant before money.

A bald eagle builds some of the largest nests of any bird.

Fact #553 · Animals

Certain birds of prey can spot small animals from great heights.

Fact #483 · Animals

Certain owls hunt silently because of specialized feather structures.

Fact #542 · Animals

A tarantula can shed its exoskeleton as it grows.

Fact #563 · Animals

The mantis shrimp has some of the most complex eyes in the animal kingdom.

Fact #442 · Animals

A hedgehog rolls into a spiny ball when threatened.

Fact #555 · Animals

Penguins can drink salt water because of specialized glands.

Fact #362 · Animals

Some animals use camouflage to avoid predators.

Fact #336 · Animals