What’s the first thing you see when you look at these birds? For me, it’s their incredible diversity of color! And it’s not only tropical birds—even cold climates produce blue Steller’s Jays, red House Finches, yellow goldfinches, and pink rosy-finches. Or consider the ruby gorget on a Broad-tailed Hummingbird, flashing its iridescent hue when the sunlight hits it just right. How can feathers be all these colors? It varies.

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