Expecting a paywall?
Not our style.

We are on a mission to create a more informed public. Your contribution will sustain trustworthy journalism, available to everyone. Can you help?

Yes, I’ll Donate
© 2025 St. Louis Public Radio
St. Louis Public Radio is a listener-supported service of the University of Missouri–St. Louis.
St. Louis Public Radio
Morning Edition
St. Louis Public Radio
Morning Edition
Next Up: 9:00 AM 1A
0:00
0:00
Morning Edition
St. Louis Public Radio
0:00 0:00
Available On Air Stations

It’s in the genes: researchers find the key to the Cardinal’s red hue

Flickr | Cardinal Rehabber
Cardinal Rehabber

Cardinals are known for their bright red plumage, a color that gives birds an advantage when attracting mates. But what gives them this attractive hue?

It’s all in the genes, say scientists at Washington University in St. Louis.

In the journal Current Biology, researchers reported finding a gene that is activated in the skin and feathers of red birds. When red birds eat foods with yellow pigments, an enzyme linked to that gene converts those pigments to red.

Birds that have the gene need to consume lots of yellow pigments to develop that red plumage, said Joseph Corbo, a professor of immunology and pathology at Washington University.

Corbo said that could explain why red birds have more success finding mates.

"It's an indicator that they are otherwise healthy and getting a lot to eat," he said. "So that's an indication that they might be a good mate."

Red factor canaries have been around since the 1920s, when bird fanciers wanted canaries with red feathers. So they crossbred yellow canaries with the red siskin.

"We thought this would be a good entry point to understanding how red birds make red feathers," said Corbo, who compared the genomes of the three birds.

Scientists are studying more species of red birds to understand how the gene works.

Send questions and comments about this story to feedback@stlpublicradio.org.

Support Local Journalism

St. Louis Public Radio is a non-profit, member-supported, public media organization. Help ensure this news service remains strong and accessible to all with your contribution today.

Eli is the science and environment reporter at St. Louis Public Radio.