Trochilidae
Watching hummingbirds is a breathtaking experience. There are enough clues that they are birds, but so much else of what they do is so completely wacko. They come in psychedelic packaging. They fly backwards, and they can hover in one place. Their acceleration and deceleration are barely within the bounds of physical laws. They flap their wings so fast that all you can see of them are two blurs. And yes, you can hear the humming. All those adaptations are designed to capture the nectar market, but they are so energy intensive that the birds have to go into a state of torpor when they rest. In the remaining time they have to ingest twice their body weight's worth of food.
15 unique species photographed in this family