Each sugary snack is also pollinated with pollen left over from the bird's previous meal.

Each of these sugary snacks also pollinates the flower being visited with pollen left on the bird from previous meals. That's just a rough idea of what hummingbirds can do in several seconds. But if we hang around a little longer, we might see their aerial acrobatics put to a more dangerous test. Hummingbirds keep track of which flowers they've recently drained, as well as those they plan to drain next. And each bird will fight ruthlessly to defend this floral territory from their only real competition: other hummingbirds.