fundamentals of eDNA

If I took one thing away from class this week it is to really be aware of targets and intentions when conducting a study with eDNA. Lecture on Monday focused on having three things in mind when designing a study: DNA state (extracellular or within the cell), the type of cell, and the environment in which one collects the eDNA. All of these play into the methods one will use to collect, extract, and store their samples. For example, in Foote et al. (2012), they used a method similar to one used in a freshwater environment, to try and detect species in a marine environment. Because it was early in the development of eDNA, it makes sense that maybe methods were not as well-developed as they are now. If the study were re-conducted now, I would hope that larger volumes of water would be collected, and then filtered before doing any extraction. But, the point I was trying to make was that methods should differ between marine and freshwater environments to yield the best results possible.

There was lots of discussion on Monday about standardizing protocols for eDNA, and although I think it is important collection standards are met, the foci of so many researchers varies greatly. So, it does not make sense for all of the methods to be standardized, when there are so many different things to consider. For example, my research involving detection of white sharks will be completely different from another student investigating harmful algal blooms. The methods that we use should be different! Another fun week with great topic points to think about moving forward into the field season.