Hummingbirds and pineapples: Why this ancient relationship hits the evolutionary sweetspot

High above the rainforest floor, tiny ponds form in the leaves of plants perched on tree branches.

Frogs breed in these ponds, alongside insects, microbes and even tiny crustaceans, creating miniature ecosystems suspended high in the canopy.

These are the bromeliads—the remarkable plant family that also gave us air plants, the towering 12-meter (39-foot) "Queen of the Andes", and the pineapple on your terrible pizza. ...