words by Rob Barrie, Science and Technology Editor
A discussion on insects, teamwork and my summer research placement.
Since childhood I have always been fascinated by insects, but after a summer of researching ants in a secluded wood in East Sussex, that fascination turned to pure amazement.
A 2009 study by researchers at Arizona State University and Princeton University revealed a remarkable finding – ants perform tasks with more rationality than humans. Obviously, this is not a case of intelligence quotient (IQ). The origin of ant rationale can be found in their sociality. They innately aggregate into colonies and are one of the model organisms for eusociality – the most sophisticated level of sociality. Though they possess a queen, colonies do not possess any hierarchical divisions. Her sole role is in reproduction – she carries no colony organisational responsibilities. And yet, despite no chain of command existing, ants divide labour amongst themselves perfectly.
The resulting behaviour, which has a near optimum efficacy, arises from the collective actions of individuals. It is here where the rationale is generated. Collective decision making, especially where individuals have less options, leads to more accurate outcomes. Such decisions could be choosing a nest site – studies have proven that ants can make sophisticated choices based on various qualities of nest sites that include ambient temperature and nest material availability. When aggregated too, decision errors by a single ant simply become drowned out by the overwhelming amount of correct choices by the rest of the colony. Thus, despite their simple brains, this adaptive behaviour is what makes ants so rational.
I was privileged enough to be accepted onto the Junior Research Scheme (JRA) at the University of Sussex last summer. I was thrilled to be investigating cooperative behaviour in wood ants – Formica rufa – and pursue our understanding of them. My research question centred around ant to ant interactions: “Is precise cooperation amongst ants needed for effective collaborative movement?” was my question, and my hypothesis was that it is needed.
I used the principle of ants collaborating to move an item as a framework to test my hypothesis. A wooden disc was placed on their nest blocking an entrance, encouraging them to move it. Each ant that joined the disc was tracked and analysed.
After approximately sixty trials, helpful behaviours were observed the most – indicating that ants do prefer to join an item near an existing ‘pulling’ ant. There was not, however, a statistical link between this and movement of the disc which indicates a level of imprecision. Ants also had a preference of joining position on the disc itself, preferring to join on the side opposite to that of nest entrance, thus indicating possible pre-emptive ‘knowledge’ of wanting to move the item away to stop occlusion of the entrance.
My results were not what I expected. Though many of the interactions were imprecise in nature, an adaptive consequence of movement still arose, and the disc was no longer covering the entrance. The ants did show a preference for useful joining positions, which indicates the potential existence of underlying biases that provide the framework for cooperation in large colonies.
I thoroughly enjoyed my research on ants. I found their collaboration arising from imprecise interactions captivating. As humans, we often associate imprecision with undesirable results. This study, therefore, is but just a small example of how we still have much to learn from our tiny six-legged friends.