A Taxonomy of Movement

One of the goals of my residency at the Andes Sprouts Society was to document the movement of composting worms. This goal was part of a larger plan to observe and document movement as a way to connect science and art, part of my sabbatical activities.

I got wonderful results from observing the worms move, though it wasn't easy, especially at first. Worms hate light, and I knew that if I tried to film them I would be observing their back ends as they slid into the comfortable dark world of their bin.

With this in mind I came to the residency prepared with a couple of infrared lights, which I knew the worms wouldn't mind. Alas, the solar panels that were supposed to provide electricity at the cabin hadn't been installed yet. As in many instances of the residency, I had to improvise.

I mixed up a medium of sand (for texture) and while clay slip (to trace their movement) and let the worms move freely through that medium in an environment that was exposed to indirect (cloudy) light. Since they didn't have anywhere to hide, I was able to approximate their natural movements, or at least to extrapolate how worms might move in their natural state if we could observe such a thing.

I was enchanted by the way their bodies made beautiful curves in the medium, the way they seemed to pulsate as they activated a sequence of muscles, and the way they formed sharper curves with the part of their bodies leading the movement. 

Several hours of recording yielded about 15 minutes of video, some of which I'm including here. 

After observing the worms for hours in an inorganic substrate I decided to trace their movement in a two-dimensional medium of ink. I found them to be willing and talented collaborators whose work I documented here in an earlier post. Seeing the worms work with the ink gave me some insights into the way we might classify their movement.

First we have to consider that as "unlimited" as the worms' movement seems (and we can assume it would be more so in the three-dimensional compost bin habitat) there are certain constraints. For example, the musculature of the worms limits the way they move in certain ways. Gentle arcs, broadly rounded curves, and body pulses are three things that come to mind. Another constraint, consider that worms moved one way in a "natural" inorganic substrate of sand and clay slip but differently on a smooth surface with ink. So within the large taxonomic class of "red wiggler movement" we can see that there are variations depending on the immediate environment of the worms.

Worm movement is one of multitudes of types of animal movement, which we might classify together because of their common genetic origin.

Consider another large taxonomic class of plant movement, which Darwin studied in detail. In a post I made in my blog "Botany Without Borders" I wrote some about plant movement, which is highly varied and includes growth, endogenous locomotion, locomotion by wind and water, and locomotion by the agency of other organisms. 

We are not limited to classifying movement by genetic category and that might not even be a satisfactory way of looking at things. Consider the movement of water vapor over a pond, the flow of a stream, the movement of a sand dune, the movement of a rock as it breaks through freeze-thaw action, or the movement of continents over time.

In a sense all of these movements are abstract signals that exist when we observe them. They are part of the world and they partially define the world but they are a tiny sliver of what the world is about. As a scientist or an artist, it is my job to interpret movement through an aesthetic moment and articulate it in a meaningful way (through some kind of communicative message) to other humans. 

It seems to me that a taxonomy of movement holds enormous potential for further study as I continue to explore connections between the world of art and science.