Imagine you are taking a stroll around your neighborhood or park when you hear the sounds of an insect orchestra.
This imagined soundscape is created by the muscular movements and vibrations of sap-feeding insects, the treehoppers. It isn’t like the familiar vocalizations made by cicadas or crickets. Instead, it is richer and more varied. Some sounds sound like songs, while others are more similar to those made by machines and musical instruments. Even a single plant can emit noises that are “as loud as a busy street.”
Ed Yong, a Pulitzer Prize-winning science journalist, explains in An Immense World that humans wouldn’t be able hear the treehoppers’ songs if they were walking on a real path. Yong is accompanied by scientists who have a laser vibrometer. This device converts treehopper vibrations into audible sounds that can be heard by human ears. The “horrifying, mesmerizing” sounds leave Yong “dumbfounded”.
This book, which follows 2018’s I Contain Multitudes is Yong’s second. He writes with a perfect blend of scientific rigor as well as personal awe. Communication through surface vibrations is a cool example. It extends beyond treehoppers to spiders and elephants. And it even includes this interesting fact about frogs. Frog embryos can hatch quickly if a snake comes up with a hard bite. But they ignore rain, wind and footsteps. Yong wrote, “They have agency.” They have an environment.”
Jakob von Uexkull, a zoologist, made the term Umwelt famous in 1909. It refers to the perceptual world each animal experiences, a very specific type of “sensory bubble”. Our dog stops walking and smells every bush and tire. She’s taking in more than we do through our sensitive noses. This is because dogs and humans have different sensory bubbles called Umwelten.
Yong examines the Umwelten of animals through chapters that are dedicated to light, color, pain, heat, contact and flow, sound, echoes, electric fields, and magnetic fields. The final two chapters discuss how the senses interact and how noise pollution has affected animal senses. Slowly, the theme Yong starts to develop takes shape as he writes that while our Umwelt feels natural, it is only one way to perceive the world.
It is all we know and we often mistake it for everything else. We tend to “frame animals’ lives in terms our senses, rather than theirs”.
Yong doesn’t care about the two reasons that scientists study animal senses. To better understand ourselves and to use knowledge of animals’ senses to create new technologies, Yong is not interested. His perspective was refreshing to me: “Animals don’t just serve as stand-ins for people or are fodder for brain-storming sessions.” They are worth their own value.”
Did you know that the majority of insects are deaf? Cows’ visual fields wrap around so they can see all three sides of the room. Magnetoreception is the only sense that doesn’t require an associated organ. It is used by green sea turtles to “read” Earth’s magnetic fields when they return home from 1,200 miles away.
While magnetoreception is an ability humans use very rarely, some animals’ sensory capabilities are completely unavailable to us. Some electric fish can “recognize the size, shape and distance of objects near them” by creating “electric images…from patterns of voltage dancing across their skin.” The click sounds of clicking are what dolphins use to navigate.
“If a dolphin echolocates upon you, it will sense your lungs as well as your skeleton. It is capable of sensing shrapnel in war vets and pregnant women’s fetuses. Based on their air bladders, it can easily distinguish between different species of fish.
This is not to say that humans cannot echolocate at all. Yong walks with Daniel Kish, a man who had both his eyes removed early in life due to aggressive cancer. Kish emits clicks as he walks, rides, or hikes. These clicks allow him to detect the shape and location of everything, from cars and houses to trees and buildings, using echolocation. Even the most skilled human echolocators cannot do what dolphins can.
The book has a lot of admiration from me. One thing that I am not sure about is the choice made by Yong, as shown in sentences such as this: “A dolphin clicks with his nose and listens to its jaws.” The word “it”, as opposed to a living, thinking entity, is more appropriate here. A different sentence would be “Dolphins click with their noses, listen with their jaws” and it would seem more in line with Yong’s apparent respect for animals as valuable individuals. Scott Simon wrote last summer for NPR that “if a cat and dog share your domicile, then I’ll venture to guess that you don’t refer to the four footed family member who lies on your back, licks your face, or sleeps in your lap… as ‘it’.” Full disclosure: Simon asked for more respective pronouns for animal species. I signed Simon’s letter.
Our insistence on bright lights that disturb dark skies and our way of living that makes incessant noises from all kinds of machines, including air and land, is seriously affecting other animals’ ability to use their senses correctly. There is hope because “sensory polluting” is an ecological advantage: When lights and engines are turned off or adjusted, conditions improve instantly. We can help protect the beautiful Umwelten around us by turning off lights that interfere with the migration of sea turtles and migrating birds, as well as reducing noise levels through the use of sound barriers.
As many others, I have relied on Yong’s reporting at The Atlantic throughout COVID-19. He opened up the rapidly-changing world pandemic science and made it accessible to me. Yong now brings to life with An Immense the animal sensory worlds of other animals that co-exist with ours and how we can protect them. This is a remarkable amount of scientific data that he has compiled and presented in a compelling way, making it seem easy. It’s not easy. It is a remarkable achievement.
Barbara J. King is a William & Mary biological anthropologist emerita. Animals’ Best Friend: Putting Compassion at Work for Animals in Captivity, is her seventh book. Follow her @bjkingape
