The United States was a more colorful place when flocks of Carolina parakeets flew across the sky like daytime fireworks, flashing pops of orange, yellow, and green.

The country’s only native parrot species ranged from southern New England down to Florida and as far west as Colorado, but the last one died in captivity at the Cincinnati Zoo in 1918. Since then, the Carolina parakeet has symbolized the perils of extinction in the United States, much like the dodo has on the global stage.

A century after the last parakeet soared over America, a mystery endures: Was the demise of the 12-inch-long bird entirely driven by people? Farmers, who saw them as crop pests, easily eliminated whole flocks, since the