Sonoran Desert: The Living Desert at the Edge of Everything

The Sonoran Desert is among the hottest deserts in North America and one of the most biologically diverse in the world. That combination is not accidental. It is the product of a particular geography: a desert low enough and far enough south to receive two rain seasons, one in winter from Pacific storms and one in summer from the monsoon that sweeps up from the Gulf of Mexico. The dual rainy seasons support a complexity of plant and animal life found nowhere else.

There are more than two thousand species of plants in the Sonoran Desert. There are more species of bat than anywhere else on the continent. The desert hosts hundreds of species of birds. The saguaro cactus, which grows only here, is itself an ecosystem: its flowers feed bats and birds and bees. Its cavities, carved by Gila woodpeckers, become nesting sites for elf owls and small raptors. Its fruit feeds javelinas, coyotes, and the O'odham people who harvest it. When the saguaro dies, the dried woody ribs are used by the O'odham as harvest poles and building material. The plant gives completely.

The desert looks still. It is not still. The Sonoran is active in ways that require a particular kind of attention, a willingness to slow down and look at things that do not announce themselves. The desert tortoise moving at its imperceptible pace across a gravel flat has been moving across this landscape for millions of years. The coyote whose howl you hear at night moves ranges measured in dozens of miles.

The border that runs through the southern end of this desert was drawn by humans. The desert does not observe it. The javelinas, the jaguars still occasionally documented crossing from Sonora, the migratory birds, the O'odham whose territory it bisects: they move across it as they have always moved, because the desert is older than any line drawn on a map.