Echo Chambers

When I was a child, my favorite bedtime story was called Stellaluna. Each night as I nestled under my covers, I would insist that my mom read it to me. The book follows a young fruit bat named Stellaluna who becomes separated from her own mother and finds herself among a nest of birds. Despite feeling like an outsider, she learns their ways—until she is eventually reunited with her bat family, vowing to stay friends with the birds. It’s a story about both embracing and transcending our differences: that which makes us unique.

There are many aspects of bats that make them extraordinary, starting with the unique evolutionary niche they occupy as the only mammals able to fly. The oldest known bat fossils date back to 50 million years ago, and these already had wings—meaning that it remains a mystery among scientists as to when and why bats actually gained the ability to fly, making them somewhat of a marvel. More than that, a study published by researchers at the University of Tennessee found that the Brazilian free-tailed bat can reach speeds of up to 100 mph, making it the fastest mammal on Earth (for comparison, Cheetahs can only reach 70 mph). 

What makes bats even more remarkable is how they navigate the world. While large bats mostly feast on fruit and find their way with sight, smaller species rely on sound to hunt insects and rodents. Using a technique known as echolocation, they produce high-pitched sounds and then listen for the echoes that are reflected back by their environment, allowing them to perceive their surroundings and pinpoint prey. A recent study found that bats can even identify insects sitting stationary on a leaf; while one might think the bug would blend in, the leaf acts as a perfect mirror, meaning that bats can detect when their echoes are weakened by an insect in the way. 

Using this sophisticated sonar system, bats are able to see sound—a process that behavioral ecologist Inga Geipel has likened to “having music around you all the time.” So how do they drown out unwanted noise? For this, their ears have been expertly designed by evolution, able to zero in on high frequencies that we humans would easily miss, and overlook low-frequency noises in the vicinity that might otherwise distract them. Perhaps even more notable is that every bat has its own unique “voice” to which it can attune itself. Through honing in on and hearing their own voice, these nocturnal animals are able to discern their way through the darkness.

In some social species, these unique voices also allow bats to recognize each other; according to National Geographic, false vampire bats (Megaderma lyra) are able to distinguish each other by vocalization. Another study, published in Behavioral Ecology last year, found that Molossus molossus bats forage in groups, using echolocation calls to communicate with one another and share information about feeding grounds. And as in Stellaluna, mother bats can locate their pups by their individual sounds—even among millions of other bats, per The Nature Conservancy. This is especially important because bats only have one pup per year, making them particularly vulnerable to extinction.

Despite the stigma that surrounds these creatures, bats serve a number of vital functions in maintaining healthy ecosystems, from insect population and pest control to pollination and seed dispersal. We humans rely on them more than many realize; 80 medicines come from plants that rely on bats to pollinate them, according to the Department of the Interior. More than 500 tropical plants and 300 species of fruit are pollinated by bats, including avocados, bananas, guavas, and mangoes. And yet, due to habitat destruction and disease, over half of the bat species in the U.S. are in dramatic decline or considered endangered.

A question I am often asked is “what can I bring to this movement?” and to that, my answer is always the same: yourself. Like bats, we all have our own unique voices. This can be hard to remember in a world that is full of so much noise. In our echo chambers and catacombs of comparison, we must work to listen for our inner voice, which can help us determine our own individual path. In so doing, every detail of our environment—every leaf, every insect, every pond—can help us find our way, so that we may aid others and the larger ecosystems to which we belong. We must learn to listen to ourselves and each other. We’ll need to, when night falls.