New research provides insight into plumage evolution

During his notable trip to the Galápagos Islands, Charles Darwin collected several mockingbird specimens on different islands in the region. He later discovered that each island only contained a single species of mockingbird and no two species of mockingbird co-existed on an individual island. Due to their geographical separation, over time these birds had evolved different characteristics in coloration, behavior, and beak shape. These observations raise the question: how does a geographi