I used to think hummingbirds were just tiny, aggressive jewels that showed up at my feeder every summer.
Turns out, the mechanics of how these birds actually stay aloft while feeding are so bizarre that engineers have been studying them for decades—and we’re still finding new details. The thing is, hummingbirds don’t fly like other birds. Most birds generate lift on the downstroke of their wings, pushing air down and themselves up. But hummingbirds? They rotate their wings in a figure-eight pattern, generating lift on both the downstroke and the upstroke. It’s more like insect flight than bird flight, honestly, which is why some researchers call it “insect-style hovering.” Their wings beat roughly 50 to 80 times per second, depending on the species, and the smaller the bird, the faster the beat. I’ve watched slow-motion footage of this and it’s mesmerizing—the wing doesn’t just flap, it twists at the shoulder joint in ways that seem anatomically impossible.
Here’s the thing: their shoulder joints are wildly flexible compared to other birds. The humerus bone can rotate almost 180 degrees, allowing the wing to flip upside down on the backstroke. That means the leading edge of the wing stays forward even when the wing is moving backward, which maintains lift throughout the entire cycle. It’s exhausting just thinking about it.
The Metabolic Cost of Hovering Is Absolutely Brutal for These Tiny Birds
Hovering burns energy at a rate that would kill most vertebrates. A hummingbird’s heart can beat over 1,200 times per minute during flight—roughly 20 beats per second—and their metabolism is so fast they need to consume about half their body weight in sugar every day. They’re basically living on the edge of starvation constantly. During the night, they enter a state called torpor, where their metabolic rate drops by up to 95 percent, because otherwise they’d starve to death in their sleep. I guess it makes sense when you consider that hovering requires about 7 times more energy than forward flight for these birds. Wait—maybe that’s why they’re so territorial? Every flower is a potential life-or-death resource.
How Their Tongues Actually Work Is Weirder Than You’d Expect
For years, scientists thought hummingbird tongues worked like little straws, sucking up nectar through capillary action. Nope. High-speed cameras revealed that the tongue actually has two grooves that split apart when it enters the nectar, then close around the liquid as the tongue retracts—it’s more like a trap than a straw. The tongue darts in and out about 13 to 17 times per second while the bird hovers, which means the bird is coordinating wing beats, hovering position, and rapid tongue flicks all at once. The energy expenditure during feeding is slightly lower than during regular hovering, but not by much. Some species have tongues that are longer than their entire body, which seems excessive until you realize they need to reach deep into tubular flowers that co-evolved with them over millions of years.
The Aerodynamics Are Still Not Fully Understood, Even Now
Despite decades of research, there are still gaps in our understanding.
Researchers have used everything from wind tunnels to particle image velocimetry to study the vortices created by hummingbird wings, and the data is… complicated. The wings create a leading-edge vortex on both strokes, which provides extra lift, but the exact contribution of each vortex to total lift varies by species, wing shape, and flight speed. A 2005 study showed that roughly 75 percent of lift comes from the downstroke and 25 percent from the upstroke, but more recent studies suggest it might be closer to 60-40 in some species. Honestly, the variation makes sense given that there are over 300 species of hummingbirds, each with slightly different wing morphology. What works for a tiny bee hummingbird (the world’s smallest bird at about 2 grams) might not scale up to a giant hummingbird (which weighs around 20 grams, still tiny by bird standards). The physics of flight at that scale—where air feels more viscous and inertia matters less—is just fundamentally differnet from larger birds.
Anyway, next time you see one at a feeder, just remember: that little bird is pulling off a mechanical and metabolic feat that we still can’t fully replicate with drones.
