Migration control: A distance compensation strategy in ants

©The Author(s) 2016. This article is published with open access at Springerlink.com. Migratory behaviour forms an intrinsic part of the life histories of many organisms but is often a high-risk process. Consequently, varied strategies have evolved to negate such risks, but empirical data relating to their functioning are limited. In this study, we use the model system of the househunting ant Temnothorax albipennis to demonstrate a key strategy that can shorten migration exposure times in a group of social insects. Colonies of these ants frequently migrate to new nest sites, and due to the nature of their habitat, the distances over which they do so are variable, leading to fluctuating potential costs dependent on migration parameters. We show that colonies of this species facultatively alter the dynamics of a migration and so compensate for the distance over which a given migration occurs. Specifically, they achieve this by modulating the rate of ‘tandem running’, in which workers teach each other the route to a new nest site. Using this method, colonies are able to engage a larger number of individuals in the migration process when the distance to be traversed is greater, and furthermore, the system appears to be based on perceived encounter rate at the individual level. This form of decentralised control highlights the adaptive nature of a behaviour of ecological importance, and indicates that the key to its robustness lies in the use of simple rules. Additionally, our results suggest that such coordinated group reactions are central to achieving the high levels of ecological success seen in many eusocial organisms

Where did it all go wrong? Implementation failure - and more - in a field experiment of procedural justice policing

Objectives: This paper presents the findings from a retrospectively conducted qualitative process evaluation to the Scottish Community Engagement Trial (ScotCET). The study explores the unanticipated results of a randomised field trial testing the effect of ‘procedurally just’ modes of road policing on public perceptions of police. The ScotCET intervention failed to produce the hypothesised results, producing instead significant, and unexplained, negative effects on key aspects of public perception. The present study seeks to examine, from the perspectives of officers implementing the experiment, what the impacts (intended or otherwise) of participation were. Methods: Group interviews were held within the ScotCET experiment ‘units’ to explore how officers had collectively interpreted and framed ScotCET, and responded as a group to its requirements/ demands. Nine groups were held over a 5 month period post experiment completion. Results: Findings indicate that communication breakdowns during the ScotCET implementation led to misunderstandings of its aims and objectives, and of the requirements placed on officers. Within a context of organisational reform and perceived organizational ‘injustice’, commonly cited aspects of police culture were invoked to facilitate officer non-compliance with aspects of the experimental intervention, leading to implementation failures, and, possibly, a diffuse negative effect on the attitudes and behaviours of experiment officers. Conclusions: Organizational structures and processes, and coercive top-down direction, are insufficient to ensure successful implementation of policing research, and, by implication, policing reforms, particularly those that demand alternative ways of ‘doing’ policing and ‘seeing’ citizens. Greater investment in organisational justice and encouraging openness to evidence-led knowledge is needed to promote change