Is a Roadrunner a Cuckoo? The Roadrunner's Family Explained

Where the roadrunner fits in the cuckoo family

The cuckoo family, Cuculidae, is a large group of roughly 150 species found on every continent except Antarctica. It includes the well-known common cuckoo of Europe and Asia, the North American yellow-billed cuckoo, the koels of Asia and Australia, the anis of the American tropics and the large coucals of Africa and Asia.

The greater roadrunner (Geococcyx californianus) and the lesser roadrunner (Geococcyx velox) make up the genus Geococcyx, a name that means “earth cuckoo”. With a few other American species, such as the striped cuckoo and the forest-floor ground cuckoos of the genus Neomorphus, they form a subgroup usually called the New World ground cuckoos.

What makes a roadrunner a cuckoo

At first sight a roadrunner looks more like a slim pheasant than a cuckoo. Scientists group it with cuckoos because of features of its skeleton, feathers and DNA, and some of these are easy to see.

• Zygodactyl feet: each foot has two toes pointing forward and two pointing backward, the classic cuckoo arrangement. It is the reason roadrunner tracks look like an X.
• Body shape: a long, graduated tail, a slender body and a strong, slightly curved bill are typical of many cuckoos.
• Genetics: DNA studies confirm that roadrunners sit firmly within the cuckoo family, close to the other American ground cuckoos.

What sets roadrunners apart is their lifestyle. Most cuckoos live in trees and fly well, while roadrunners spend nearly all their time on the ground, running rather than flying, in hot, dry country.

Do roadrunners behave like cuckoos?

The word cuckoo often makes people think of brood parasitism: laying eggs in other birds’ nests and letting the hosts raise the young. The common cuckoo of Europe is the best-known example. But only about 40 percent of cuckoo species do this. Many others, including most American cuckoos, build nests and care for their own young.

Greater roadrunners are devoted parents. A pair builds a stick nest in a cactus or thorny shrub, both adults incubate the 3–6 eggs for about 20 days, and both feed the chicks. There are a few records of roadrunners laying eggs in the nests of common ravens and northern mockingbirds, but this is rare. Interestingly, some of the roadrunner’s closest relatives, such as the striped cuckoo and the pheasant cuckoo, are brood parasites, which shows how this habit has come and gone within the family.

The dark skin trick: warming up like a solar panel

One remarkable roadrunner habit links to its desert life rather than its family. Nights in the desert can be cold, and a roadrunner saves energy by letting its body temperature fall from about 40 °C (104 °F) to about 34 °C (93 °F) overnight.

To warm up again in the morning, it sunbathes. The bird turns its back to the sun, droops its wings and lifts the feathers of its back, exposing patches of dark, almost black skin. Dark skin and feathers absorb sunlight efficiently, so the bird can regain heat without burning food energy. On cold mornings this can last two to three hours, and in winter roadrunners may sunbathe several times a day. The photo above shows a roadrunner doing exactly this in Joshua Tree National Park.

Roadrunner relatives in the Americas

Several other cuckoos share the roadrunner’s continent:

• Lesser roadrunner: smaller, with a shorter bill and fewer streaks on the chest; lives in dry scrub from western and southern Mexico to northern Central America.
• Yellow-billed and black-billed cuckoos: shy, slim birds of woodland that eat many hairy caterpillars; both migrate to South America for the winter.
• Mangrove cuckoo: a tropical species reaching southern Florida.
• Anis: black, big-billed cuckoos that live in noisy groups and lay eggs in a shared nest.
• Squirrel cuckoo: a long-tailed, rufous cuckoo of tropical forests from Mexico to Argentina.

None of these runs like a roadrunner, but all share its two-forward, two-back toes. Across the Atlantic, the common cuckoo of Europe is a summer visitor famous for its two-note call and its habit of leaving its eggs for reed warblers, meadow pipits and other small birds to raise, a life history very different from the roadrunner’s. For more about how fast the roadrunner really is, see how fast can a roadrunner run?