Across planet Earth, the animal world is full of species perfectly adapted for life in their specific niche. From polar bears ...

Spiders living in caves show how tiny genetic changes can reshape vision or cause complete blindness over generations.

These hairs are covered in tiny barbs. The spiders can flick them at predators as a form of self-defense. While tarantulas have eight eyes, they don't see well. "Their hairs are sensory structures ...

This cross section through the head of a jumping spider shows off the interior structure of four of its eight eyes. Jumping spiders have the most acute vision of any terrestrial invertebrate. In fact, ...