Pavlov's dogs conditioned to salivate at the sound of a bell demonstrated classical conditioning in 1890.

Some reptiles can live for over a century.

Fact #319 · Animals

Some frogs carry their tadpoles on their backs.

Fact #354 · Animals

The Amazon rainforest supports millions of species.

Fact #302 · Animals

A meerkat stands upright to scan for predators.

Fact #547 · Animals

Some butterflies use mimicry to avoid predators.

Fact #556 · Animals

Bats are the only mammals capable of sustained flight.

Fact #58 · Animals

A moose has long legs adapted for walking in snow.

Fact #518 · Animals

A cheetah can accelerate from 0 to 60 mph in a few seconds.

Fact #363 · Animals