Up the mountain

I donned my nitrile gloves, wiped down the lab bench with ethanol, and opened my freezer. One hundred and eighty coral samples stared me in the face. Each one rested quietly in its small ethanol tube. They had no idea what was about to happen to them, but I did. The battle belonged to me.

Friends, I have spent a lot of time extracting DNA from Porites lobata. I mean, a lot of time. So much time. I started with a round of 90 samples in 2019. That was followed by another round of 90 in late 2021. Don't forget about the 150 samples I did in 2022, either. I couldn't even tell you at this point how much time I've spent extracting DNA. The process is pretty repetitive, to the point that I treat it like a form of meditation. 

Take a wild guess what I've been doing this week. Yep, extracting DNA from Porites lobata. This time, the corals in my dataset are parents that contributed offspring to our experiments last spring. We did a ton of experiments - to the point that it was hard to keep them all straight. We tested whether a coral's ability to tolerate high temperatures is inherited from its parents. We tested whether cryopreserved sperm could fertilize eggs spawned hours to days later. We tested whether juvenile corals could survive outside their home environment. We tested whether parents belonging to different genetic groups could fertilize one another's gametes. We even georeferenced corals to test if genetically distinct corals occupied different areas on a reef. 

Every single one of those experiments has the same thing in common: we need to know who the parents are. Specifically, we need to know which of the three lineages each of our corals belongs to. And for that, we need to extract DNA. 

Once I'm finished with the extractions, I'll hand off the samples to my collaborators at Boston University for the next steps. Identifying which lineage each coral belongs to is a super labor-intensive process, but hey, at least it works. (My attempt to develop a quick-and-dirty method went nowhere.) With 180 corals in my freezer and countless hours ahead of me at the lab bench for just the extraction step, it can feel like climbing a mountain. The good news is I've been to the top of this particular mountain before. I know I can do it.