The photographs are amazing...I love hummingbirds and so just for the pictures this is worth a good look, but it is full of amazing facts. There is a bit of quite technical information about the aerodynamics of hummingbird flight and the extraordinary structure of their wings and the 'structural' color of their iridescences, not all of which I quite grasped but that was all right. But what could give me more joy than discovering that there exists in the Andes the giant hummingbird (Calypte helenae), which is 8 1/2 inches long and has a wingspan of a foot? Nothing. Maybe the bee hummingbird which is only 2 1/4 inches long, or the sword-billed hummingbird with a four inch beak. Learning that both bats and moths can also hover, and more efficiently, than hummingbirds was also exciting. Hummingbirds when cold can go into what is called torpor (I do too, but it's not quite the same), also called 'noctivation' where they slow down everything, appear to be almost dead, can be handled but quickly come back to life with the warmth of a hand. They can fly backwards and upside down when threatened. A few species, like the rufous in its travels from western north America through the Rockies to southern Mexico, migrate hundreds and thousands of miles. In tropical areas where there are more types, they form what is known as 'guilds', up to 20 species coexisting peacefully occupying different niches in a landscape. A few species go 'lekking', where males congregate and perform and females choose among them. They use spider webs t build their nests.
They are amazing.