What Is Environmental DNA? ... And How Can It Be Used To Conserve Biodiversity?

As animals and plants pass through an environment they leave behind traces of their presence in the form of feces, shed skin or fur, leaves, pollen, mucus, etc.  All of these contain DNA, termed environmental DNA (eDNA), as it is not collected directly from the animal but, rather, is found in environmental samples, such as soil and sediment.  Once collected, environmental samples can be analyzed using DNA sequencing technology to identify the community of organisms present in that location.

Other methods of assessing biodiversity are often invasive, potentially with negative impacts on the fauna and flora they are assessing.  Additionally, it is often difficult to locate and therefore monitor rare and endangered species. Environmental DNA is a non-invasive method of detecting hard to observe, rare or endangered species. Organisms merely need to leave DNA as they pass through the environment rather than being physically trapped or sighted. As such, environmental DNA can be used establish a more accurate assessment of the species in an environment whilst causing less disturbance and harm to those organisms.