Territoriality in ants revisited: iconic collective displays reflect resource, not territorial defense in meat ants Irid
- PDF / 574,550 Bytes
- 6 Pages / 595.276 x 790.866 pts Page_size
- 61 Downloads / 210 Views
SHORT COMMUNICATION
Territoriality in ants revisited: iconic collective displays reflect resource, not territorial defense in meat ants Iridomyrmex purpureus Shaolin Han 1
&
Mark A. Elgar 1
Received: 18 July 2020 / Revised: 18 July 2020 / Accepted: 19 August 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Non-injurious, collective ritualized displays may have evolved in some species of ants as a means of resolving contests for key resources, without causing a drain in worker numbers through injury. Colonies of the Australian meat ant, Iridomyrmex purpureus, deploy numerous workers to engage in collective displays, which are widely understood to be involved in maintaining exclusive territories. A combination of field surveys and behavioral assays revealed that display grounds do not delimit borders that define exclusive territories. Rather, the proportion of workers from a focal colony found in a quadrat declines monotonically with distance from the nest. In addition, we documented collective displays around food trees, where workers congregated in greater densities and engaged in more aggressive behavior. These results refute the assumption that colonies of I. purpureus establish territorial boundaries by collective displays. Rather these collective displays may be related to the defense of specific resources, including food trees and nest sites. The difference in the level of aggression among displaying workers at different locations may reflect a balance between the benefits of defending a particular resource and an unappreciated cost of escalation. Keywords Collective displays . Territorial behavior . Resource defense . Contest escalation
Introduction Animal contests are pervasive and govern access to key resources, including territories and food resources (Hardy and Briffa 2013). Injurious and fatal contests are rare, and most are resolved by signals, including traits and behaviors that convey information about the resource holding potential of the contestants (Hardy and Briffa 2013; Stevens 2013). Social animals, including ants, also contest resources using collective displays, which often involve simultaneous contests between many hundreds of individuals (Sherratt and MestertonGibbons 2013; Adams 2016). Species of ants form exclusive Communicated by: Sean O'Donnell Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00114-020-01693-y) contains supplementary material, which is available to authorized users. * Shaolin Han [email protected] 1
School of Biosciences, University of Melbourne, Melbourne, Victoria 3010, Australia
spatial territories, with intruders repulsed through physical contests or signals (Levings and Traneillo 1982; Hölldobler and Wilson 1990; Adams 2016). Collective displays in ants are thought to function in maintaining territorial borders but, for most species, this is only inferred (Table S1, Supplementary Material) and it is typically unknown whether the location of these displays defines the territ
Data Loading...
