Hummingbirds

In the sugar-charged lives of the world’s smallest birds, sexual selection has taken over, with males vying for mates by competing in leks or defending rich nectar resources. Hummingbirds showcase a dizzying array of plumages, almost all of which rely on odd tail plumes or the angle-sensitive iridescence of their feathers for their effect. The extreme maneuverability of these most acrobatic of birds seems to engender a lack of concern about predators, making them easy to approach near sources of food. Burning energy so fast during the day that most species cannot make it through the night on a stomach full of nectar, most go into torpor every night, even in tropical environments, to reduce energy loss.