Why are vultures bald? Why do some orangutans have big cheeks? And if giraffes have long necks to help them reach the highest leaves, why do they mostly eat low-lying shrubs? Embark on a whirlwind tour around the world as we explore some of nature's most-fascinating evolutionary wonders.

When did we start riding horses? When did dogs become man's best friend? Answering questions like these help us understand our impact on other species' evolutionary journeys - a crucial step toward ensuring our survival doesn't necessarily come at the expense of their own.

Clownfish can change genders, male seahorses carry their young, and some snakes have remnants of leg bones-but why? Discover how significant evolutionary changes inside these creatures have equipped them for survival.

From penguins whose salt-removing eye glands shield them from the harsh ocean to caterpillars whose fake facial markings are meant to mimic a snake's, animals have evolved in amazing ways to see and be seen. Meet these creatures and see how they use eyes and illusions to their advantage.

Bees and ants work selflessly toward a common goal. Bonobos maintain social harmony through sex, while meerkats organize themselves with military-level discipline. What do these creatures all have in common? The basic recognition that their survival hinges on an ability to work and live together.

The older a species, the better it is at adapting to change. From the ancient lineage of sharks, who've evolved into perfect predators, to the living fossil known as the bichir, get a closer look at some of nature's enduring evolutionary masters.