Extraction Methods Reflection
This week we talked about collection and extraction methods, standardization, and how the choices we make when choosing methodology impact our results. I think the discussions really hammered home some points that have started coming up more and more, such as the importance of consistency, tailoring your methods to your research questions and species, and understanding that the field has changed since it’s early years and will continue to do so. There are so many choices to make when designing eDNA studies, and I can see how it could get overwhelming quickly. It has been really helpful to lay out some of the different options and weigh their biases, advantages, and drawbacks.
I had previously read the Foote et al (2012) paper and there is a poster from some similar previous work in my lab hanging on the wall where I filter, so the difference in detection between controlled environments and natural environments is somewhat ‘old news’ to me. However, it was really interesting to discuss how methods have been updated and improved even since the early 2010’s. What seems strange to us now (ie small sample volumes), may have seemed totally reasonable back then (ie to compare to the more established freshwater studies). I wonder what we do now that will make us look back and cringe!
The Deiner et al (2014) paper was interesting in its comparison of different extraction protocols, a very relevant conversation as we approach the start of sample analysis for various projects. What kind of caught me off guard was the discussion on precipitation as a capture method, mostly because I had not heard a ton about it previously. It was interesting to learn about it from an informational perspective, and I was glad to see that this paper showed favor for filtering over precipitation, since that is what we use for the index sites and other projects I have been involved in. I’m curious as to if the decision to use filtering was as debated as the extraction protocol, or if that was simpler to settle on.