Concordia College - Moorhead, Minnesota |


Amphipod Antics

Ingrid Jacobson ’21, Biology Major – Summer 2019

Sometimes, you have excellent lab days. And sometimes, you rip your preserved organism in half without even trying.

In Dr. Jennifer Sweatman’s lab, we monitor the overall health of the Florida Bay. In 2018, Dr. Sweatman and her summer research interns went down to Florida Bay and collected many samples of a tiny, marine, shrimp-like crustacean called an ‘amphipod.’ Now, Dr. Sweatman’s lab is processing and analyzing these amphipod samples.

What do amphipods have to do with measuring the health of the Florida Bay? Amphipods are present in almost every aquatic environment on Earth, from Antarctica to Concordia’s own Prexy’s Pond. Due to their prevalence, they are excellent organisms to collect for analysis. Amphipods are also bioindicators – their health reflects the well-being of their overall environment. Dr. Sweatman’s dissertation was on this very topic.

Figure 1: Dr. Sweatman and her summer interns collecting samples from the Florida Bay, Summer 2018. Photo by Brooke Swarthout

In addition to being bioindicators, amphipods are also excellent organisms to use in the lab because of their size. Amphipods are very small, and so once they are collected (Figure 1), large numbers of amphipods can be preserved in ethanol and taken back to the lab for identification.

Figure 2: A Cymadusa compta specimen from Dr. Sweatman’s lab. Photo by Ingrid Jacobson

In addition to being delicate, amphipod specimens are also hard to work with because there are so many different species (over 9,950 species of amphipods exist). The learning curve on amphipod identification is intense, and at times can feel insurmountable.

Amphipods are excellent creatures to use for aquatic ecosystem monitoring. However, amphipods have a few downsides. Due to their extremely small size, researchers require dissecting microscopes to appropriately identify their species (Figure 2). Although they aren’t alive, these amphipod samples still require a delicate touch, and my untrained hands have inadvertently decapitated many-a-creature. Just last week, I successfully identified an amphipod. Without letting go of my tweezers, I looked up to tell my lab mates. Unfortunately, the movement of my shoulders was too much for the preserved amphipod. That poor specimen was left in thirds.

How can one survive working with these delicate creatures without going insane? I’ve found three strategies for dealing with amphipods:

  1. Deep breathing. Keep calm and use slow, steady movements to manipulate the amphipod. I’ve found that when I perform the more delicate maneuvers on an inhale, the amphipods rip much less. The most delicate maneuvers I save for in-between my heart beats, to minimize the micro-shakes in my hands.
  2. Taking a break. If my hands are too shaky from being tensed up, I’m going to make more mistakes. I can also use a break to reset my patience meter, which will allow me to pay more attention to the smaller details, and in turn achieve success in identification.
  3. More Cowbell.Everything is better with more cowbell.

I hope that you all can benefit from my strategies, even if you don’t deal with amphipods. Maybe they can be helpful if you deal with sculpting, or painting, or small children.