Volcanic sulfur may make barn owls grow redder feathers
Exposure to sulfur-rich, volcanic soil appears to encourage the production of reddish pigments
The chest and belly plumage of barn owls (one shown) varies considerably across the globe, ranging from nearly white to a much darker copper color. New research suggests a boost in pheomelanin from sulfur exposure may give the feathers of ones living on volcanic islands a reddish or yellow tint.