Arizona's saguaro cactus has evolved to thrive in the extreme climate of the Sonoran Desert, but after decades of rising heat, even these towering icons are showing signs of stress.

The program looks at the history of the saguaro, its life cycle and how the great cactus uses - and is used by - various plants, insects and animals. 03/27/2018 Problems playing video?

And it's only fitting — the saguaro cactus is an Arizona icon. The towering cactuses only grow in the Sonoran Desert, meaning Arizona is one of the few places on earth where you can spot them.