According to the latest estimates, insects account for probably 4 to 6 million of the species of creatures living on the planet—but relatively little is understood about how they get around. Anyone who’s ever been hunted by a bloodthirsty mosquito knows that insects can indeed fly, and fly well. But as theoretical and applied mechanics professor Steve Strogatz puts it, “If you look at traditional aerodynamics, insect flight doesn’t work.”

For Strogatz’s TAM colleague Z. Jane Wang, figuring out how and why it does work is an overarching passion. A 34-year-old physicist, Wang has been fascinated by the subject ever since she ran into a book called Mechanics of Swimming and Flying by Steve Childress, who later became her advisor at New York University’s Courant Institute of Mathematical Sciences. “It was purely accidental,” she says. “I wanted to do something different, and I thought, ‘Hmm, that would be an interesting thing to look at.’”

Accidental or not, within a couple of years she’d made a breakthrough. She devised a computer simulation that—taking into account both rapidly oscillating wings and the complex motion of air—proves that insect flight does conform to the physical principals of aerodynamics after all. “One hundred years ago, when people started designing planes, they failed by copying birds,” Wang says. “Now that we understand things a little better, can we rethink flapping flight?”

It’s Wednesday toward the end of spring semester, and Wang is sitting outdoors at Collegetown Bagels, nibbling on a cherry strudel and drinking a cup of green tea. A bed of vivid tulips and daffodils has drawn her to a table at the edge of the patio; the only brighter color in sight is her chartreuse Oxford shirt. “Insect flight is a mystery to me,” she says between bites. “The first question is, how do they stay airborne? The second question is, how do they maneuver? And ultimately, how did they evolve? Planes are great engineering achievements, but they don’t have the same sense of mystery.”

The mystery of natural flight has endured for centuries and captured such great minds as Leonardo DaVinci, who designed several “ornithopters,” flying machines that copied birds. Early in the 20th century, engineers came to the conclusion that bumblebees “can’t” fly—at least they shouldn’t be able to, given their ratio of body weight to wingspan. The pronouncement sparked an enduring scientific “urban legend”; there’s even a self-help book out there called Bumblebees Can’t Fly, intended to inspire people to transcend their perceived limitations.

“It’s a really hard problem in math,” Strogatz says of insect flight, “because two things—the wing and the air—affect each other.” But bumblebees do fly. And if science can’t explain it, it clearly isn’t the bees’ fault; it’s a gap in the science. Wang and her colleagues, including University of California at Berkeley biologist Michael Dickinson, are now on the vanguard of finding new ways to understand a phenomenon that’s untold millions of years old. “Engineers say they can prove that a bumblebee can’t fly,” Dickinson has said. “And if you apply the theory of fixed-wing aircraft to insects, you do calculate that they can’t fly. You have to use something different.”

The issue, Wang says, is in great part a matter of fluid dynamics. “Insects are using their wings to play with fluid and to get forces,” she says. “It’s very much like when you row, you use oars to maneuver. But it’s not quite the same, because when you row, you can lift the oars out of the water, and insects can’t lift their wings out of air.”

And the situation is even more complicated, because all flying things aren’t created equal. As they get smaller, their relationship to the fluid changes—as do the physics of flying. To illustrate, Wang picks up her paper teacup, covered by a plastic lid, and rotates it gently. “If I do this, I don’t even have to ask you to look at the water,” she says. “You can imagine the water is swirling around, and if I stop, it’s probably going to keep swirling for a little while, right? But if I do the same thing with a cup of honey, it’s harder to get a swirl, and if I stop, it probably stops immediately. For insects, it’s as if they’re living in honey, because they’re very small. The viscous effect is much more important.”

But for birds, she says, the air is more analogous to the tea; consequently, they glide a lot. “It’s inertia,” she says. “So once they start to glide, they can keep generating lift for some distance.” Insects, on the other hand, can’t glide like that, so they had to evolve efficient wing strokes to keep themselves airborne. “There are certain strokes insects have to do in order to fly that birds don’t have to do,” she says. “From a biology point of view, the wing structure is also different. And very few birds can hover; the hummingbird is remarkable. But big birds can’t hover, so there’s a size limitation too.”

At the moment, Wang is particularly interested in dragonflies; because they’re so maneuverable, she says, “I think they’re capable of doing something special.” She offers swimming as an analogy: while most insects do a treading stroke, dragonflies do the butterfly. And speaking of butterflies... Wang is interested in them, too. With neurobiology and behavior professor Tom Eisner, she’s been studying cabbage butterflies, which fly in a “fluttery” trajectory, possibly to avoid predators. Her students have been collecting specimens, and next year Wang—who up until now has been predominantly a theorist—plans to have a colony of them in her lab in Thurston Hall. “In the process of working with Jane, I’ve come to admire her quite a great deal,” says Eisner. “She’s everything a scientist should be—curious and persistent and totally wrapped up in solving the questions that capture her mind. When she sees the potential of something, she takes off like a chariot hitched to a star.”

A native of Shanghai, China, Wang earned an undergraduate degree in physics from Shanghai’s Fudan University, then a Ph.D. in physics from the University of Chicago. She did postdoctoral work at Oxford University and at Courant, where she returns every summer. “She’s energetic, funny, and dynamic,” Strogatz says. “I think her work is very original and brilliant. She has resolved what had been a big gaping hole in fluid mechanics.”

In addition to insect flight, Wang is also fascinated by how leaves fall; when the subject comes up, she scours the Collegetown Bagels tulip bed for a “helicopter,” one of those dual-winged maple seed pods that kids love to play with. “Here’s one,” she says, brandishing a slightly brittle specimen. “It’s an old one. I don’t know what it will do. It may not drop very well.” She gives it a few tries, and it finally spins and flutters away satisfactorily. Then Wang pulls a credit card out of her wallet, holds it parallel to the table, and lets go. It drops like a stone. “It’s very boring, right?” she says, then drops it again, this time perpendicular to the table. The card hangs in the air a bit on its way down. “This tells you what happens when a piece of wing doesn’t have any muscle,” she says. “It’s just passive dynamics—there’s one force, which is gravity. There’s gravity on it, so it wants to fall, but as it falls it cuts through the air. What you don’t see is the motion of air, which interacts with this piece of wing and pushes it around.”

Those fluid dynamics issues, obviously, intersect with Wang’s work in insect flight, but the potential implications don’t end there. Her research may also have applications in biology, as in how blood and the heart interact, and in engineering, such as how bridges are affected by wind—for example, Washington state’s infamous Tacoma Narrows suspension bridge, which collapsed in 1940 a mere four months after it was completed.

Other possible applications for Wang’s work range from the lighthearted to the deadly serious—literally from video games to the military. Wang envisions her computer models leading to the creation of a game simulating insect flight, with the player as the insect. “We can’t really fly as people,” she says. “I can give you a pair of wings, but it doesn’t matter how hard you try. It’s a question of the ratio of your muscles to your body; once you grow over a certain size, you can’t fly by using your own power. So it would be interesting and fun to design virtual flight. I’m imagining this living theater where you’re actually flying. You could feel the forces just like what you’d feel when you’re swimming, and on the screen you could see the insects taking off. That would be cool.”

But Wang’s funding doesn’t come from Nintendo; it comes from a National Science Foundation Early Career grant, an Office of Naval Research Young Investigator grant, and an Air Force Office of Scientific Research grant. Those agencies, Wang says, are funding her pure research, which she calls “a little bit of a luxury.” “In that regard I’m very lucky,” she says, “because I can mostly think about work instead of asking for more money.”

The military is particularly interested because it hopes to design surveillance and reconnaissance planes the size of a human fist. “Their fantasy is to build these very small airplanes,” Wang says, “and when you scale it down to the size of insects, fixed-wing technology may not work very well. It doesn’t have the maneuverability they might want.” Instead of reinventing the wheel—or the wing—researchers are looking to nature for inspiration. At Berkeley, Dickinson is part of the Micromechanical Flying Insect Project, which is designing tiny robots that fly using insect flight principles. Why mimic insects? “It’s very difficult to design a stroke,” Wang says. “If you want to swim, you learn from somebody.”

Wang oversees the work of four Ph.D. students whose projects include insect flight, paper falling, and computational fluid dynamics, and she teaches courses in math modeling, calculus for engineers, and biofluid dynamics. She lives downtown just steps from The Commons and relishes her daily commute hiking up and down the Cascadilla Gorge Trail (or a nearby street in the winter); she also enjoys watching movies at Ithaca’s arthouse cinemas. But when asked what she does for fun, Wang says she doesn’t believe in making artificial separations between work and the rest of her life. “I enjoy skiing and skating in winter; hiking and rowing in summer. But if work itself is not fun, and we try to get fun mostly from doing other things,” she says, “that is as if we replace the main course with dessert.”

Beth Saulnier is an associate editor of Cornell Alumni Magazine and the author of the Alex Bernier mysteries, published by Warner Books/Mysterious Press.