Lambert here: And now for something completely different….
By Jackie Higgins, who worked for Oxford Scientific Films for over a decade, with National Geographic, PBS Nova and Discovery Channel. She has also written, directed and produced films at the BBC Science Department. Posted from alternet.
For the ancient Greeks, the owl symbolized wisdom, but the Romans saw it as a bad omen. Their myths speak of an owl strix who stalked the night and fed on human flesh. Ovid’s poem fasti describes how such a demon crept into the nursery of the sleeping Prince Proca and was found hunched over the cradle, sucking blood from the newborn. This supernatural owl has changed over time. In Italian, strix became strega, meaning witch; in Romanian, strigoi is a vampire; and in macbeth, Shakespeare once again redefines the owl as “the fatal hunter” whose cry calls for the death of King Duncan. Like its legendary counterparts, the great gray owl, nebulous strix, dwells in the shade. He lives in the icy north, in the dark dense coniferous forests of Russia, Alaska and Canada. At night he hunts. Scythe-like talons and a hooked, knife-sharp beak make the great gray owl a fearsome predator. By day, it remains hidden. Although one of the largest of its kind, its dark, mottled plumage blends in with tree branches to atomize the bird’s silhouette, making it as nebulous and insubstantial as mist. Moreover, on a still moonlit night when snow covers the landscape and muffles the sound, the owl swoops down on its prey and barely breaks the silence.
The calmness of the owl’s flight is unparalleled; its wing beat produces a sound so soft that it is almost imperceptible. “While we have known for centuries”, said Professor Nigel Peake of the University of Cambridge, “what is not known is how owls are able to fly silently.” His lab is one of the few in the world trying to learn from this avian acoustic stealth. For years the focus has been on feathering along the leading and trailing edges of the kite. The front ones have tiny stiff beards that point forward like the teeth of a comb, while the back ones are soft and fringed. They work together to break up and then smooth out air currents as they flow on and off the wing, dampening any noisy turbulence. Recently, Peake has focused on a third element: the luxurious feel of the kite. “We were among the first to think about the aerodynamics of this velvet,” he told me. In 2016, he collaborated with American scientists to take a closer look at the smooth surface of the wings of various species of owls, including the great grey. They saw that the birds’ primary feathers were covered with a millimeter of fine down.
“Microscope photographs of the down show that it consists of hairs that form a forest-like structure,” Peake said. Explain. “The hairs initially rise nearly perpendicular to the surface of the feather, then bend in the direction of flow to form a canopy.” This Lilliputian “forest” greatly reduces pressure fluctuations and turbulence as the air passes over the wing. The researchers, funded by the US National Science Foundation and the US 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 only stealthier surveillance planes or submarines, but also a significant drop in daily noise pollution from, for example, wind turbines, computer fans and even passenger planes that daily criss-cross the planet.
“Owls have a lot to teach us about making our own world quieter,” Peake said. “No other bird has wings that scatter sound so that its prey cannot hear it coming.” The great gray is neither seen nor heard, and this natural spectrum also seems endowed with a supernatural sense. From a distance of about 30 meters (100 feet), it can spot mice or voles with astonishing accuracy, even those hidden under mounds of untouched snow.
Scientific research brought the owl out of the shadows and returned it to Athena, the Greek goddess of wisdom. Through this creature, we learn what it means to hear: not only to detect sounds but to create rich and perspective soundscapes. We discover our talent for discerning whispers from whispers, then locating and layering them to build cathedrals of sound. The silent bird also guides us to make this world a better place: whether by redesigning technology to dampen unwanted noise or improving the lives of those less fortunate. “I am as deaf as I am blind” wrote American deafblind activist Helen Keller to her doctor in 1910. “The problems of deafness are deeper and more complex, if not greater, than those of blindness. Deafness is a much worse misfortune. The owl sits on the blind man’s shoulder, bearing the gift of sight. One day, alongside her extended avian family, she may offer others the gift of sound.
This excerpt is from Sentient: how animals illuminate the wonders of our human sensesby Jackie Higgins (Atria Books, 2022) and was produced for the web by Earth | Food | Lifea project of the Independent Media Institute.