A Label Of Health: A Previous Immune Challenge Is Reflected In The Expression Of A Female Plumage Trait

In the bird world, the ladies traditionally size up and select their mates. But a recent study suggests that sometimes the guys get to be choosy too. The authors show that ornamental white bands on the wings of cryptic brown female Common Eiders is directly affected by an immune challenge during breeding. Immune challenged females produced feathers with smaller white fringes.

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