On the scent

Collecting environmental DNA, or eDNA, from water samples is an established technique for tracking aquatic organisms. Now, new research into airborne animal DNA might do the same for flying animals. Two separate experiments, conducted at Hamerton Zoo Park in England and Copenhagen Zoo, have revealed that there is enough DNA in the air alone to identify all nearby animals. Using fans attached to a filter, the teams were able to collect genetic material from a variety of sources, including saliva, fur and faeces, and successfully detect the different species living inside and outside the zoos. This may prove to be a valuable, non-invasive method for tracing endangered animals, even when they can’t be seen.