The Nematode Crane Game

Since I completed microplastics extractions and processing for all of my samples, I took this past week to count and nematodes from my samples and make slides for identification. Although this step can be taxing because I sit for hours at the microscope without my glasses on counting every nematode in a sample, which can amount to > 1,000, the slide-making portion can be quite fun, hence the title of today's blog.

Nematodes tend to have a recognizable body structure that I refer to as cooked spaghetti. They are usually longer than they are wide and have a slight tapering at the mouth and rear end. However, nematodes, much like cooked spaghetti, can be quite flimsy and floppy, which can make picking them up using the small extraction hook quite difficult. It helps when a nematodes has looped around or resembles a curly fry (many examples in the picture above), because I can get the hook under one of the loops and have a sturdy area of the body to grab on to. Just like the classic arcade crane game, the shape of the item you are trying to pick up can help or hinder your success. Some nematodes, however, do have different body shapes, resembling more of an American football shape, rather than spaghetti. These nematodes can be excruciatingly frustrating to pick up out of the sample because the hook doesn't have much to grab onto and the game becomes more of a balancing act than an arcade game. 

What happens if I can't pick up the nematode easily? As nice as it would be to pretend like the difficult nematode wasn't there, bias is not something that I am trying to add to my work. Body shape can sometimes be related to nematode taxonomy, so excluding a nematode because it is challenging is certainly not advisable.I can use the hook to move the nematode up higher in the dish and refocus the microscope so that the focus is on one nematode rather than the whole group. With better focus, I am more easily able to maneuver the hook and grab onto a nematode. Sometimes it does take a few minutes to complete a single nematode if it is being quite challenging, but all in a day's work.

As a reminder, this post is the last weekly update for a few weeks, as I will be taking my preliminary examinations. Usual posting will resume Thursday, October 21 with an update from the field, since I will be going into the field that week to do more sample collection.

---