Foraging on the wing: How can ecologically similar birds live together?

A spat between birds at a backyard birdfeeder highlights the sometimes fierce competition for resources that animals face in the natural world, but some ecologically similar species appear to coexist peacefully. A classic study in songbirds by Robert MacArthur, one of the founders of modern ecology, suggested that similar wood warblers—insect-eating, colorful forest songbirds—can live in the same trees because they actually occupy slightly different locations in the tree and presumably eat different insects.