Although there have been a number of suggestive studies recently investigating personality in ants, a new study published in Behavioral Ecology tested whole-colony personality in a controlled lab setting, The authors showed that colonies of funnel ants show consistent differences in behaviour, with some colonies opting for a bold, risk-taking strategy, and others being more conservative, an effect that was not due to differences in age or experience of the colonies.
The existence of colony-level personality is something I anecdotally observed during my own PhD, and a finding that adds to our understanding of social insects as superorganisms. The superorganism view of social insects is a powerful one, as long as we keep in mind the ways that social insects differ from other groupings that we might consider to posses 'individuality' - workers are not all genetically identical. Their genes and interests differ, and conflict is bound to ensue.
The researchers then observed how each colony foraged for food and explored new environments. They counted the number of ants foraging, exploring, or hiding during set periods of time, and then compared the numbers to measure the boldness, adventurousness, and foraging efforts of each group. They also measured risk tolerance by gradually increasing the temperature of the ants’ foraging area from 26°C to 60°C. Ants that stayed out at temperatures higher than 46°C, widely considered to be the upper limit of their tolerance, were considered risk-takers. The scientists found strong personality differences between colonies, they reported online this month in Behavioral Ecology. Some were bold, adventurous risk-takers with highly active foragers. Others were shy, risk-averse, and fearful of new environments. Their foragers were less active, and they were less inclined to search for food at very high temperatures.