Birds of Uruguay: white-throated hummingbird
As might be clear from the amount of photos of that specific subject I take, I like birds. And sometimes, when I research the backgrounds of birds, I become more interested than other times. So I thought, why not share? Take the case of the white-throated hummingbird (Leucochloris albicollis). This species is one of the two species of hummingbird that can be found all-year round in Uruguay, the other species being the Gilded hummingbird (Hylocharis chrysura). Like all hummingbirds, this is a small bird that hovers in front of flowers to drink their nectar. In Uruguay, this bird is called "Picaflor garganta blanca". "Picaflor" is the generic Spanish name for hummingbird and means something like "flower pincher". I think that name is quite apt. Although the necessary energy for flying is obtained mostly from nectar, they do in fact eat other food like small insects to obtain the necessary proteins.
Hummingbirds belong to the family trochilidae, which only exist natively in the Americas. Being amongst the smalles of birds, they are capable of hovering with incredible precision in front of the flowers from which they suck their nectar, their wings beating around 70-200 times per second. To sustain the incredible amount of energy needed to be able to do this, their metabolism is fast. Very fast. In fact, they have the highest metabolism of any homeothermic animal. Their metabolism is in fact so fast, that they would die from starvation if they would sleep like other animals do. To conserve energy, hummingbirds go into a special state called torpor when they sleep. This is a state similar to hibernation, where their metabolic rate drops to around 1/15th of their normal rate. Although I couldn't find metabolic information specific to the white-throated hummingbird, measurements in other species have measured heart rates of up to about 1.250 beats per minute (!) with breathing rates of about 250 per minute, even in rest! So even when in torpor, they have a heart rate higher than a human being in rest. They still lose about 10% of weight per night! These birds don't have any risk of becoming obese.
The wings of the white-throated hummingbird, and in fact all hummingbirds birds, are true pieces of art. Small, light and strong. A hummingbird's wings are unlike any other wings found in birds. Hummingbirds can do things no other bird can do. Apart from the hovering, they can fly forwards, backwards, sidewards en even upside down for a short while! They are true acrobats. The reason a hummingbird is capable of these remarkable feats is in their special anatomy. Unlike other birds where the shoulder is a normal joint, the shoulder of a hummingbird is a ball and socket joint that allows them to rotate their wings. They don't "flap" their wings as other birds do: they rotate them. When flying, their wings move in an oval pattern, and when when hovering they move in an "8" pattern, or "∞" if you will.
These little birds can be seen everywhere in Uruguay. It defends its territory quite aggressively and can often be seen chasing hummingbirds of the same or other species.