Environmental DNA (eDNA) is a new emerging technology that is used to detect endangered species, study the impacts of climate change, alert us to invisible threats such as pathogens, and assess the overall health of terrestrial ecosystems.
What is the difference between DNA and eDNA?
DNA (Deoxyribonucleic Acid) is the hereditary material in organisms that contains the biological instructions for building and maintaining them. The chemical structure of DNA is the same for all organisms, but differences exist in the order of the DNA building blocks, known as base pairs. Unique sequences of base pairs, particularly repeating patterns, provide a means to identify species, populations, and even individuals.
Environmental DNA (eDNA) is DNA that is collected from a variety of environmental samples such as soil, water, snow, or air, rather than directly sampled from an individual organism. As various organisms walk and interact with the environment, DNA is expelled and accumulates in their surroundings from various sources.
In aquatic environments, eDNA is diluted and distributed by currents and other hydrological processes, but it only lasts about 7–21 days, depending on the environmental conditions. Exposure to UVB radiation, acidity, and heat can degrade eDNA.
How to collect eDNA
Collecting eDNA samples is quick and easy. The main concern is to make sure that each sample is collected without any contamination. This is only accomplished by not touching the sample with your hands. You should always use fresh gloves, new paper bags or envelopes, and sterilized tweezers when collecting each sample. Once a sample is collected, write the details on the bag or envelope of when and where you found it. It should be kept frozen until it is ready to be run through the lab. The site should also be photographed extensively to show the location, environment, and conditions of where it was collected.
How eDNA can be beneficial to Bigfoot research?
eDNA found in a soil sample may assist in the search for Bigfoot. Soil samples taken from active research areas, ground nest sites, and hair samples, are ideal candidates for eDNA analysis.
Recently, members of the Olympic Project, a group of citizen scientist investigators in Washington state, became aware of multiple ground nests of distinctive construction, which yielded hairs from an unknown hominoid. Expert opinion is that these unusual nests were not made by bears. This was an ideal situation for eDNA testing to be collected and studied.
An obstacle in the search for Bigfoot has been the inability to successfully sequence DNA from hair samples on the basis of their distinctive morphology. Unfortunately, an actual Bigfoot specimen is required in order to compare DNA and eDNA samples against to determine a match. Many times, eDNA results have indicated a type of primate species that is unknown or not known to be in the area, or just comes back as being ‘unknown’.
Unfortunately, the cost of an eDNA test is too expensive for most researchers and can run approximately $1,000 per sample. Eventually the price should go down once more labs start doing it.
In conclusion, eDNA can be a powerful tool for identifying where these magnificent elusive creatures have been out walking or resting. So when in doubt, collect it! You never know what you will find out about it in the future, once the cost of testing becomes more affordable for everyone.