The Aerodynamics of Velvet: What Humans Can Learn from Owls

Lambert here: And now for something completely different….

By Jackie Higgins, who has worked for Oxford Scientific Films for over a decade, along with National Geographic, PBS Nova, and the Discovery Channel. She has also written, directed, and produced films at the BBC Science Department. Cross-posted from Alternet.

To the ancient Greeks, the owl symbolized wisdom, but the Romans saw it as an evil omen. Their myths tell of an owl-like strix that stalked the night and preyed on human flesh. Ovid’s poem Fasti describes how such a demon slipped into the nursery of the sleeping prince Proca and was found hunched over the cradle, sucking the newborn’s blood. This supernatural owl changed over time. In Italian, strix became strega, meaning witch; in Romanian, strigoi is a vampire; and, in Macbeth, Shakespeare once more recast the owl as ‘the fatal bellman’ whose shriek summons King Duncan’s death. Like its legendary counterparts, the great gray owl, Strix nebulosa, inhabits the shadows. It lives in the icy north, in the dense, dark conifer forests of Russia, Alaska, and Canada. By night, it hunts. Scythe-like tal­ons and hooked, knife-sharp beak make the great gray owl a fearsome predator. By day, it stays hidden. Although one of the largest of its kind, its dusky and mottled plumage blends with the tree branches to atomize the bird’s silhouette, making it as nebulous and insubstantial as mist. Moreover, on a still moonlit night where snow blankets the landscape and deadens sound, the owl swoops on its quarry and barely breaks the silence.

The quietness of the owl’s flight is unrivaled; its wing beat makes a sound so soft that it is nearly imperceptible. “While we’ve known this for centuries,” said Professor Nigel Peake of the University of Cam­bridge, “what hasn’t been known is how owls are able to fly in silence.” His laboratory is one of a few around the world trying to learn from this avian acoustic stealth. For years, the focus had been the feathers along the wing’s leading and trailing edges. Those at the front have tiny stiff barbs that point forward like the teeth of a comb, whereas those at the back are flexible and fringed. They work together to break up, then smooth the air currents as they flow over and off the wing, damping down any noisy turbulence. Recently Peake homed in on a third ele­ment: the wing’s luxuriant touch. “We were among the first to think about the aerodynamics of this velvet,” he told me. In 2016, he collabo­rated with scientists in America for a closer look at the smooth surface of wings from various owl species, including the great gray. They saw that the birds’ primary feathers were covered with a millimeter of fine fluff.

“Microscope photographs of the down show it consists of hairs that form a structure similar to that of a forest,” Peake explained. “The hairs ini­tially rise almost perpendicular to the feather surface but then bend over in the flow direction to form a canopy.” This Lilliputian ‘forest’ reduces pressure fluctuations and turbulence dramatically as the air flows over the wing. The researchers, funded by the U.S. National Science Foundation and the U.S. Office of Naval Research, recreated this topography in plastic. Testing their prototype in a wind tunnel, they found it reduced sound so well that they patented the de­sign. This discovery promises not simply stealthier surveillance aircraft or submarines but also a significant drop in everyday noise pollution from, say, wind turbines, computer fans, and even the passenger planes daily crisscrossing the planet.

“Owls have much to teach us about mak­ing our own world quieter,” said Peake. “No other birds have wings that scatter sound so their prey can’t hear them coming.” The great gray is neither seen nor heard, and this natural specter also seems endowed with a supernatural sense. From a distance of some 30 meters (100 feet), it can pinpoint mice or voles with uncanny precision, even those hidden beneath mounds of virgin snow.

Scientific research has coaxed the owl from the shadows and restored her to Athene, the Greek goddess of wisdom. Through this creature, we learn what it means to hear: not simply to detect sounds but to create rich and perspectival soundscapes. We discover our talent for discerning whispers of whispers, then locating and layering them to build cathedrals of sound. The silent bird also guides us toward making this world a better place: whether through redesigning technology to subdue unwanted noise or improving the lives of those less fortunate. “I am just as deaf as I am blind,” wrote the American deaf-blind activist Helen Keller to her doctor in 1910. “The problems of deafness are deeper and more complex, if not more important, than those of blindness. Deafness is a much worse misfortune.” The owl sits on the shoulder of the blind, bearing the gift of earsight. One day, alongside her wider avian family, she may also offer others the gift of sound.

This excerpt is from Sentient: How Animals Illuminate the Wonder of Our Human Senses, by Jackie Higgins (Atria Books, 2022) and was produced for the web by Earth | Food | Life, a project of the Independent Media Institute.

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About Lambert Strether

Readers, I have had a correspondent characterize my views as realistic cynical. Let me briefly explain them. I believe in universal programs that provide concrete material benefits, especially to the working class. Medicare for All is the prime example, but tuition-free college and a Post Office Bank also fall under this heading. So do a Jobs Guarantee and a Debt Jubilee. Clearly, neither liberal Democrats nor conservative Republicans can deliver on such programs, because the two are different flavors of neoliberalism (“Because markets”). I don’t much care about the “ism” that delivers the benefits, although whichever one does have to put common humanity first, as opposed to markets. Could be a second FDR saving capitalism, democratic socialism leashing and collaring it, or communism razing it. I don’t much care, as long as the benefits are delivered. To me, the key issue — and this is why Medicare for All is always first with me — is the tens of thousands of excess “deaths from despair,” as described by the Case-Deaton study, and other recent studies. That enormous body count makes Medicare for All, at the very least, a moral and strategic imperative. And that level of suffering and organic damage makes the concerns of identity politics — even the worthy fight to help the refugees Bush, Obama, and Clinton’s wars created — bright shiny objects by comparison. Hence my frustration with the news flow — currently in my view the swirling intersection of two, separate Shock Doctrine campaigns, one by the Administration, and the other by out-of-power liberals and their allies in the State and in the press — a news flow that constantly forces me to focus on matters that I regard as of secondary importance to the excess deaths. What kind of political economy is it that halts or even reverses the increases in life expectancy that civilized societies have achieved? I am also very hopeful that the continuing destruction of both party establishments will open the space for voices supporting programs similar to those I have listed; let’s call such voices “the left.” Volatility creates opportunity, especially if the Democrat establishment, which puts markets first and opposes all such programs, isn’t allowed to get back into the saddle. Eyes on the prize! I love the tactical level, and secretly love even the horse race, since I’ve been blogging about it daily for fourteen years, but everything I write has this perspective at the back of it.

13 comments

  1. Nikkikat

    I had an experience with a great horned owl. One summer night as I stood in the yard, there was no breeze. Air was very still. I felt an almost imperceptible movement of air over my head. I looked up to discover the underside of the owl as it dipped down in flight maybe a couple of feet above my head. It then swept up and on to the top of a telephone pole in the yard. Beautiful experience. I will never forget. Completely silent.

  2. Chet G

    Owls are wonderful, and thank you for this extract.
    I’ve been lucky enough to photograph a few owl releases as well as encountering the occasional owl in nearby forests. One happy surprise was during a night of insomnia when I peeked through the closed blinds and saw a screech owl perching a few feet away in the nearby serviceberry (and so I ran, grabbed camera, and managed to get one clear photo).

  3. flora

    When I was a child dad and I were in the backyard after sunset, deep dusk but not completely dark, and dad softly said “look” and pointed. A large owl flew in low and landed on a nearby fence post. Absolutely silent. I’d never heard any bird fly in absolute silence. Not even a sparrow. This large owl, which if it had been a crow or a hawk would have made a great deal of wing noise, was absolutely silent. How could this large bird fly in close and land silently? It was almost like a dream.

    1. flora

      adding per the original post:

      “To the ancient Greeks, the owl symbolized wisdom, but the Romans saw it as an evil omen. ”

      and

      “Scientific research has coaxed the owl from the shadows and restored her to Athene, the Greek goddess of wisdom. ”

      The some of the Italian Renaissance artists adopted this ancient idea. See Michelangelo’s sculpture of Notte (Night) in the Medici Chapel sculptures. Notice the owl under “Night’s” raised knee.

  4. vao

    Testing their prototype in a wind tunnel, they found it reduced sound so well that they patented the de­sign. This discovery promises not simply stealthier surveillance aircraft or submarines, but also…

    Again, when something is learnt about the wonders of nature, military applications come first.

    1. FreeMarketApologist

      Excellent excerpt, and I’m fine with the military applications, but since the research was “…funded by the U.S. National Science Foundation and the U.S. Office of Naval Research,…“, meaning that taxpayers footed at least part of the bill for the work, why not put it in the public domain, so that any manufacturer might use the techniques to reduce the noise of their products?

      If some other country wants to use it for military purposes, they will, regardless of the patent status. Maybe the technique should be released into the global public domain so it doesn’t represent a specific military advantage, and then noise reduction techniques could be mandated for everybody’s benefit, using the commonly available method?

    2. chuck roast

      If it means that the military develops yet another weapon based upon the deep secrets of the natural world, I would prefer to learn nothing at all and simply marvel in my ignorance.

  5. Tom Stone

    I saw a great snowy owl in Oakland once, blown south by a big storm.
    I walked out my back door before dawn one morning, looked down and there it was.
    Perched on a railing and stripping and eating a feral cat.
    I must have made a sound because it looked up at me, spread its wings and hissed.
    I went back inside immediately and later picked up and disposed of the remains.
    The head was untouched and the entire spine was there but the rest had been neatly removed and eaten.
    It hung around the ‘hood a few days and then disappeared.
    That fence had upright posts 6’ apart, the wingspan was a few inches wider than that.

  6. Alex Cox

    “Testing their prototype in a wind tunnel, they found it reduced sound so well that they patented the de­sign.”

    The US Navy and their civilian chow-hounds make a copy of something which exists in nature, and then patent it? This is so sad.

  7. The Rev Kev

    Feelings about owls have changed a lot since ancient times regarding owls. I once stayed in a small German village for a while and whose mascot happened to be the owl – and you don’t do that if you have negative feelings about them.

  8. CitizenSissy

    Owls are wonderful! Used to hike at night, and the leader did very creditable (to the owls, at least) owl calls. They’d follow us on the trail for an evening of call-and-response.

    Definitely going to check out this book.

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