How an enzyme powers parrots’ colorful plumage

Parrots’ plumage dazzles with feathers in fiery reds, ostentatious oranges, luminous yellows, and verdant greens. Scientists have now discovered the molecular mechanism that controls these four colors in parrot feathers—a finding that could indicate why the birds have evolved such vivid hues. Birds like cardinals get their colorful plumage from carotenoids in their diets . But the colors in parrots’ plumage come from chemicals known as psittacofulvins, which parrots make endogenously. “Parrots are the only birds that we know of that make bright colors in this way,” says Joseph C. Corbo , a scientist at Washington University School of Medicine in St. Louis who led the study, along with the University of Porto’s Miguel Carneiro , Pedro M. Araújo , and Roberto Arbore . Using genetic mapping, biochemical assays, and single-cell genomics, the researchers discovered that the enzyme aldehyde dehydrogenase family 3 member A2 (ALDH3A2) oxidizes psittacofulvins to change their