Penguins propose to their mates by presenting a carefully chosen pebble — and rejection is common.

Some species of jellyfish can shrink and regrow their bodies.

Fact #428 · Animals

Certain frogs can inflate themselves to appear larger to predators.

Fact #377 · Animals

A chameleon changes color primarily for communication and temperature control.

Fact #431 · 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 bamboo species can grow more than a foot in a single day.

Fact #115 · Animals

Pterosaurs were flying reptiles, not dinosaurs.

Fact #628 · Animals

Some species of crabs can regenerate lost claws.

Fact #396 · Animals