The Deep History of the Sonoran Desert
The Sonoran Desert is considered to be the most “tropical” of the North American deserts. 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. It has both geographic and biologic connections with more tropical communities.