Scientists are capturing animal DNA in the air for the first time
But for many biologists, it can be almost impossible to monitor mammals that move miles every day and are careful of humans. Enter eDNA. “If we are to regenerate ecosystems, we need to understand how our conservation actions affect endangered and endangered species. But to do that we need to be able to find even the rarest, most shy, and callous species, ”wrote Michael Schwartz, senior scientist at the US Forest Service's National Center for Genomics for Wildlife and Fish Conservation. in Missoula, Montana, by e-mail. and WIRED. "We need new technologies, such as the ability of DNA to detect airborne environments."
Schwartz, who was not involved in the two new studies, has been using air, water and soil samples to track large brown bats (Eptesicus fuscus). Biological Conservation who examined eDNA samples from soil and water outside the caves where the bats live. They also used an air sampler as part of the project to see if they could take DNA in the air from an orbiting bat in Ohio. Six of the seven airborne airborne samples successfully detected their eDNA in the air, the study said, but densities were low, despite the 30 bats in the room.
Schwartz says his colleagues are updating their air sampling methods and working on a way to collect some DNA from the snow. Not only does this allow the USFS team to find out which mammal species have recently traveled over the snow pack, but digging in it will also allow them to find evidence that a particular type of animal had traveled through the area months earlier. The Schwarz group published some findings about this project in the journal Biological Conservation in 2022. Using snow trails to find shy predators like the lynx is cost-effective, efficient and definitive, he says.
Would the aero-DNA sampling method work to detect genetic material from individuals? Surprisingly yes, but almost not, one expert says. "It's possible, but it's a little more challenging," said Melania Cristescu, an associate professor of ecological genomics at McGill University, which uses eDNA to test aquatic habitats. Pieces of human DNA from hair, saliva, blood, or other genetic material left on the surface are easier to examine than air. (Swiss researchers recently solved the mystery of family ancestry using DNA from postage stamps affixed to a World War I postcard, showing the stability of the molecule in certain situations.) But it would longer to obtain a sufficiently large sample of aerial genetic material, and researchers had to be extra careful not to allow their own DNA to contaminate the filter.
With aerial DNA, the weather is also a factor. Sampling may also not work if it is wet or windy, for example, as these conditions may clean the air of DNA-carrying particles. It is also unclear how well the molecule can withstand heat or bright sunlight. “Does solar radiation reduce DNA? Maybe, but we do not know the extent, "says Clare." We do not know how far wind can spread DNA. We do not know how temperature can affect it its pollution levels. These are all very interesting questions. ”