Landscape diversity in the Sonoran Desert rivals that of any other terrestrial ecoregion on Earth, with nearly all of the planet's biomes represented, ranging from cold conifer forests to hot deserts, where frost is nearly absent and precipitation rare.

This complex of life-forms is a product of abiotic variables: soil, climate (specifically biseasonal precipitation), community ecology, evolution, and environmental gradients. The extensive niches in this system provide habitat to hundreds of species of birds, bees, butterflies, mammals, hummingbirds, and reptiles.

Its climate is virtually frost-free, and summer rainfall comes from the tropical oceans. The Sonoran Desert�s structurally diverse vegetation, which includes columnar cacti and leguminous trees, certainly differs from those of the shrub-dominated Great Basin, Mohave and Chihuahuan deserts.