Space ants!

Choosing a certain study or career to excel in gives a sense of purpose and accomplishment. However, I have always found myself interested in many different fields. I therefore found the end of high school rather stressful. How could I choose one subject to work on for the rest of my life?

Of course, I now realise that the end of high school doesn’t mean the end of a diverse education. It just means I have to seek it out myself. This is why I try and make a point of leaving my world of ecology and talk to people from different fields, believing that all disciplines have something to learn from each other.

I recently had a conversation with Thomas Johansen from the Brorfelde Observatory . From 1953-1996, Brorfelde was an engaging workplace for astronomers. Last year (2016) it opened as an exploration center, focusing on astronomy, geology, technology and nature. The observatory has 42 hectares of land and Thomas wanted to know if I was interested in doing an Ant Hunt with them. Of course! I thought. But what do ants have to do with astronomy?

Turns out that, besides having conquered most of Earth, ants have been to Space. Don’t get too excited. We have not found extra-terrestrial life. However, the pavement ant (Tetramorium caespitum) had its’ moment in Space in January 2014, when taken aboard the international space station (ISS).

The aim was to see how ants would perform collective search in microgravity compared to on Earth. Perhaps not surprisingly, they weren’t as effective. I doubt anyone would be systematic and effective in searching if they lost contact with the surface, floated around for a while and then landed somewhere different. In fact, at any one time 7 % of the ants were floating around in the best astronaut style you can imagine. Furthermore, ants communicate through odours and we know that, at least for humans, the ability to perceive odours is affected by microgravity.

This being said, isn’t it impressive that only 7 % lost contact? With no exterior aid to keep them grounded. On top of that, a lot of those who lost surface contact were able to regain it again.

“An ant that lost contact with the surface usually turned and tumbled in the air, or skidded rapidly, in the small space between the two surfaces of the arena. This indicates that the ant exerted some pressure on the surface before losing contact with it; otherwise the ant would have just floated away from the surface without turning in the air or going quickly in one direction. Sometimes an ant attached itself to another ant to climb back down to the surface. Once back at the surface an ant appeared to hold on to it by flattening its body toward the surface.” (Countryman et al. 2015).

This behaviour may relate to how ants can hold onto each other to form bridges, or balls so they stay together during a flood (see youtube video). Some ants can also glide through the air and then find contact with a tree.

The study was carried out by Deborah Gordon and her collaborators and resulted in the publication Countryman et al. (2015) Collective search by ants in microgravity, Frontiers in Ecology and Evolution 30.