No domestic bargain is more lopsided. On a low branch, a bee hummingbird female assembles a cup of plant fiber and spider silk, then turns it into an incubator; the male's part ends before the eggs demand heat. He does not build. He does not brood.This is solo labor, not a quaint exception. The female manages oviposition, incubation, and chick provisioning while sustaining the metabolic throughput...More