BY THE OPTIMIST DAILY EDITORIAL TEAM

In the lush forests of northern Belize, surrounded by hibiscus blooms, kingfishers overhead, and the busy trails of leaf-cutter ants below, biodiversity scientist Elizabeth Clare reflects on a question as profound as it is urgent: how do we measure all of life?

“You can look at a couple square feet of ground here and never possibly describe all the things that are in it,” says Clare. “Most things in the world have never been recognized by science.”

This sense of wonder is at the heart of a powerful new approach to biodiversity monitoring—one that captures the invisible traces life leaves behind. Clare and her team have found that DNA floating through the air may hold the key to understanding—and protecting—the rich fabric of species across the planet.

A footprint in the wind

Every creature, whether a leaf-cutter ant or a vampire bat, sheds tiny fragments of DNA simply by existing: skin cells, saliva, hair, even breath. These fragments drift into the environment and become what scientists call environmental DNA, or eDNA.

PhD student Nina Garrett has been experimenting with how to catch this elusive trace of life. In Belize, she places a fan and filter system inside a guanacaste tree known to house bats. The goal is to collect airborne DNA from animals inside without disturbing them. “They are shedding hair, could be little skin cells… even when they breathe out,” she explains.

Using these traces, researchers can detect not only known residents, but elusive species never physically seen in the area. It’s a tool that reveals the hidden dimensions of biodiversity—and it’s just the beginning.

From one tree to an entire nation

What started with individual trees is now scaling to an awe-inspiring national level. A collaboration between Clare’s team and the U.K.’s National Physical Laboratory (NPL) used a surprising tool: pollution monitors. These stations, set up to detect airborne heavy metals, also collect filters that unknowingly trap DNA from the surrounding environment.

Clare’s team analyzed about a year’s worth of filters. What they found was staggering: hundreds of species—insects, spiders, birds, mammals, even plants and fungi—had left their biological footprints in the air.

“It’s like a treasure hunt for biodiversity scientists,” Clare says. Each filter may hold only a whisper of life, but taken together, they form a mosaic of an entire nation’s living world.

A new way to see the planet

While traditional surveys depend on visual sightings, this airborne DNA method can detect species that humans might never see. “Airborne eDNA recovered fewer taxa overall,” says lead author Orianne Tournayre, “but detected species that are harder to spot or identify visually.”

Marine scientist Ryan Kelly, who was not involved in the study, marvels at the possibilities: “We can see the whole living world based on the DNA in the air, and we can do it all without any new infrastructure.”

This is more than just a scientific feat. It’s a new kind of planetary awareness.

Turning pollution monitors into wildlife sentinels

If filters are optimized for DNA preservation, these networks could become a standardized, cost-effective system for continuous biodiversity tracking.

“The same network designed to protect human health could become a system for protecting wildlife as well,” Tournayre writes.

This could transform how we assess conservation success, detect species shifts due to climate change, and respond to emerging threats like invasive species or agricultural pests.

And this is only the beginning.

“If we can do it at the level of a country, we can do it at a level of a continent,” Clare says. “This is something that truly could scale to huge, almost planetary measurements.”

From the breath of a bat to the winds that cross oceans, the story of life is written in the air. Now, we have a way to read it.