Do they not see the birds suspended in mid-air up in the sky? Nothing holds them there except Allah. There are certainly Signs in that for people who have belief. (Surat an-Nahl, 79)
How the tiny fliers manage to dart, hover and dive even in gusty winds.
The smallest hummingbirds weigh barely more than a penny, and the largest weigh in at just 0.7 ounces (20 grams). Despite their mini stature, hummingbirds are among the world's largest hovering animals. Hummingbirds don't fly like other birds. Instead of flapping their wings up and down, hummingbirds oscillate their wings in a figure-eight pattern. The oscillation produces lift on both the downstroke and the upstroke. When hovering, hummingbirds generate extra lift by creating a 
vortex of air on the leading edge of their wings. These wing vortices are very unstable, meaning they should vanish at the teensiest nudge. The hummingbirds have been given a clever way around that problem. Their wings produce the vortex with a high angle of attack on the downstroke. Then they flip their wings around on the upstroke, so as they shed one vortex, they produce another on the other side of the wing, thereby managing to maintain high lift forces. A gust of wind could upset this delicate balance, but it’s not so.
Another miracle is about Hummingbirds’ energy consumption.
Unlike humans who must fuel up hours before intense exercise, hummingbirds can refuel in mid-flight, as wisdom from Allah. Within several minutes of lapping up sweet nectar, the rufous hummingbird uses the just-ingested sugars to fuel more flying and hovering so it can consume more nectar.
Hummingbirds have the highest energy expenditure of any warm-blooded animal, with a heart rate of up to 500 beat per minute, blindingly fast wing beats and sustained hovering. So this bird is nearly always on the edge of starvation, needing to slurp up more than its body weight in nectar each day.
Scientists fasted hummingbirds before giving them cane nectar, a type of nectar that has a characteristic level of the carbon-13 isotope, a form of carbon having a different number of neutrons. As each bird lapped up the sugary substance, the scientists used a special device on the feeder to measure its oxygen intake—used to calculate energy consumed—and the carbon in its breath.
By comparing the energy requirement with the amount of carbon-13, they showed that within 20 minutes of feeding, the hummingbirds were supporting more than 90 percent of their hovering needs with the cane 
sugar. This is the first time anybody has shown a vertebrate animal able to support such a high fraction of exercise metabolism with very newly ingested sugar.
Compare that with a human: An elite cyclist at 60 percent of his maximum aerobic rate can only support 15 to 30 percent of his energy needs with consumed sugars. He needs a high carbohydrate meal such as spaghetti the night before an event in order to process and shuttle the sugar energy to his muscles.
When human or other animals consume meal, they can’t convert the food to energy immediately as hummingbirds. Hummingbirds are created in this way because they need the mechanism to survive; but a human does not need such mechanism. Allah creates everything in a perfect way what they need.
….. the handiwork of Allah Who gives to everything its solidity….. (Surat an-Naml, 88)
