Animals detected by their airborne DNA

Airborne DNA can identify animal species nearby. A new analysis reported simultaneously by independent research groups studying zoos in Denmark and the UK could be a valuable tool for monitoring biodiversity (Curr. Biol. 2022, DOI: 10.1016/j.cub.2021.12.014, 10.1016/j.cub.2021.11.064). Collecting environmental DNA (eDNA) from water sources is a common way for ecologists to track some species. Until now, no one had success with airborne eDNA, which is present at much lower levels, but recent advances in technology have made it possible to detect much smaller amounts of DNA. Both groups—one led by Elizabeth Clare of York University and one by Kristine Bohmann from the Globe Institute at the University of Copenhagen—created vacuum devices to suck air through filters and then amplify the fragments of DNA captured from the air. They suspect the DNA comes from animals’ saliva, skin cells, or feces. The researchers detected the DNA of animals up to several hundred meters away from their zoo enclosures, as well as some, like hedgehogs and ducks, that live in the zoo surroundings. The researchers also identified DNA from animals fed to the zoo animals. With further research, they say, sampling airborne eDNA could transform biodiversity monitoring, especially of invasive and elusive species.