I know a lot of biologists who have lists related to their work: lists of birds they have seen, lists of journals they want to publish in, lists of top wildlife spectacles they want to see, lists of species they have studied, lists of their favourite fieldwork sites.
I too have a few lists, and in writing this post I’m thinking of one list in particular: my list of the most disgusting batches of tissue samples I have ever had the misfortune to extract DNA from. It is a short but memorable list, which, as of this week, stands at four entries. And despite the large number of scat DNA samples I have worked with over the years, there are no faeces on that list!
I thought it was going to be a routine afternoon in the lab. I was planning to take subsamples from some roadkilled mammal ear tissues we had been sent. Roadkills can be a valuable non-invasive source of population genetic information for many species. The procedure goes something like this: take a 2mm subsample of tissue, finely chop it with a scalpel and forceps, and transfer the tissue to a tube with lysis buffer to incubate overnight. I had 48 samples to prepare, so was expecting to spend a couple of hours in the lab, then finish the DNA extractions the next morning.
That was the plan…