What is eDNA?
DNA, or deoxyribonucleic acid, is the molecule found in the nuclei of living cells that carries the genetic instructions for making the entire organism – the genome. Technology for interpreting and reading this code (known as DNA fingerprinting) is now so advanced that species can be identified from miniscule quantities of DNA. No longer is it necessary to have intact tissue samples or even whole cells to work with.
So-called environmental DNA (eDNA) can be extracted from water, soil, or other media, then amplified and decoded to provide evidence for the presence of a particular species without the organism ever being seen. In the UK, the technique is particularly useful for confirming the presence of great crested newts (which are protected by law) in bodies of water, saving ecological consultants many long nights of surveying work. Amy-Jane Beer
Ponds can be tested in May for newt DNA, which enters water during reproduction, and via shed skin cells and droppings.