How do hummingbirds remember which flowers they visited?

A hummingbird's hippocampus, which is responsible for memory and learning, is up to five times bigger than the hippocampus of other birds, according to a study from The Royal Society. The result is that the birds remember which flowers they've visited, their locations and when they'll have nectar again. Given that they can visit a thousand or more flowers a day and can fly 500 miles before resting, pretty amazing.