title: Parasites modulate within-colony activity and accelerate the temporal polyethism schedule of a social insect, the honey bee.
abstract: Task allocation in social insect colonies is generally organised into an age-related division of labour, termed the temporal polyethism schedule, which may in part have evolved to reduce infection of the colony's brood by pests and pathogens. The temporal polyethism schedule is sensitive to colony perturbations that may lead to adaptive changes in task allocation, maintaining colony homeostasis. Though social insects can be infected by a range of parasites, little is known of how these parasites impact within-colony behaviour and the temporal polyethism schedule. We use honey bees (Apis mellifera) experimentally infected by two of their emerging pathogens, Deformed wing virus (DWV), which is relatively understudied concerning its behavioural impact on its host, and the exotic microsporidianNosema ceranae. We examined parasite effects on host temporal polyethism and patterns of activity within the colony. We found that pathogens accelerated the temporal polyethism schedule, but without reducing host behavioural repertoire. Infected hosts exhibited increased hyperactivity, allocating more time to self-grooming and foraging-related tasks. The strength of behavioural alterations we observed was found to be pathogen specific; behavioural modifications were more pronounced in virus-treated hosts versusN. ceranae-treated hosts, with potential benefits for the colony in terms of reducing within-colony transmission. Investigating the effects of multiple pathogens on behavioural patterns of social insects could play a crucial role in understanding pathogen spread within a colony and their effects on colony social organisation.
authors.affiliation: Institut für Biologie, Martin-Luther-Universität Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany.
authors.forename: Myrsini E
authors.initials: ME
authors.lastname: Natsopoulou
authors.affiliation: Institute of Biology, Free University Berlin, Schwendenerstr.1, 14195 Berlin, Germany ; Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany.
authors.forename: Dino P
authors.initials: DP
authors.lastname: McMahon
authors.affiliation: Institut für Biologie, Martin-Luther-Universität Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Paxton
keywords: Apis mellifera; Deformed wing virus; Host; Multiple infection; Nosema ceranae; Pathogen