An Immense World

Ed Yong / Random House / 464 pages 

An elephant, a mouse, a robin, an owl, a bat, a rattlesnake, a spider, a mosquito, a bumblebee, and a human enter a school gym. An Immense World: How Animal Senses Reveal the Hidden Realms Around Us opens not with a joke, but with a thought experiment: How would each of these creatures perceive the colors, textures, smells, sounds, vibrations, electric and magnetic fields, and open space around them—and each other? How would this change, if at all, if the lights were turned off? 

So begins a remarkable exploration of what Pulitzer Prize– winning science journalist Ed Yong terms animals’ “sensory bubbles,” or “Umwelten.” “Umwelt” (singular) means “environment” in German—but Yong uses it more specifically to mean the parts of an animal’s surroundings that the animal can actually sense and experience. He reveals that the human Umwelt, though our reality, is but a sliver of all reality. We perceive only a fraction of the colors that hummingbirds do. We cannot hear the ultrasonic squeaks of rodents or the infrasonic calls of elephants or whales, smell the cornucopia of scents our dogs pick up during neighborhood walks, or register the magnetic fields that sea turtles, lobsters, and migratory birds have used for millions of years to navigate.

But, writes Yong, the purpose of the book, and of examining other animals’ senses, is not to compare animals with ourselves. Rather, it is to better understand “animals as animals.” To that end, Yong introduces us to snakes that smell with their tongues, catfish that taste with their skin, moles that feel with fingered noses, bats that echolocate, fish that electrolocate, octopuses whose arms act as individual brains, and spiders whose webs act as extensions of their minds. And with each astonishing encounter, we are reminded of just how much more there is to our stimulus-suffused world than meets any of our eyes (or tongues, or tentacles, or trunks).