LK Hodgkin, MRE Symonds, MA Elgar (2014) Leaders benefit followers in the collective movement of a social sawfly. Proceedings of the Royal Society of London B 281: 20141700 PDF
What’s it about?
Social animals maintain cohesive mobile groups by making collective decisions. Leaders facilitate this process by guiding group movements. In this paper we look at larval aggregations of the iconic Australian Steel-blue sawfly, which comprise a few individuals that consistently lead foraging movements. The field experiments that Lisa painstakingly did revealed no clear benefit to being a leader, but, crucially, individuals in groups with leaders did much better than those in groups of exclusive leaders or followers. Our study highlights the importance of recognising that when leadership is consensual, then both followers and leaders likely benefit, else leaders will have no followers.
What’s the story behind it?
“The idea behind this experiment came about after reading a paper by Weinstein et al. They looked at just 2 sawfly aggregations and found some consistent leadership occurring in the lab. I decided that such a fantastic topic needed much more investigation and so set out not only to prove that leadership was occurring in the field, but also to explore how manipulating the amount of leaders and followers would influence group behaviour and fitness. The main thing I remember about actually conducting this experiment was being freezing cold all the time. The experiment went for a month and each night I had to stay til after 10pm in the middle of nowhere on a lonely island in the dead of winter. I learnt my lesson though and the following field season I had thermals, a balaclava, waterproof gumboots and about 40 layers of socks! Much of the time was spent sitting miserably in the freezing cold and dark waiting to see when (or whether) certain aggregations would forage and as a result I managed to listen to the entire unabridged audiobook of Gone With The Wind (49 hours 7 minutes). Near the end I may or may not have been slightly crazy and talking to my sawflies in a Georgian accent.”