Experimental evidence for delayed post-conflict management behaviour in wild dwarf mongooses

  1. Amy Morris-Drake
  2. Julie M Kern
  3. Andrew N Radford

  • Curated by eLife

    eLife logo

    Evaluation Summary:

    This article will be of interest to behavioural ecologists studying aggression, within-group conflict, communication, and the use of social information. The study elegantly combines well-designed experiments with field observations to investigate the effects of within-group conflict on social behaviour. Specifically, it expands our understanding of social dynamics in group-living species by providing evidence that bystanders of within-group conflict may play a role in maintaining group cohesion. The findings provide a valuable contribution, and contrast, to existing work in this field.

    (This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 agreed to share their name with the authors.)

Reviewed by

Read the full article See related articles

Listed in

Log in to save this article

Abstract

In many species, within-group conflict leads to immediate avoidance of potential aggressors or increases in affiliation, but no studies have investigated delayed post-conflict management behaviour. Here, we experimentally test that possibility using a wild but habituated population of dwarf mongooses ( Helogale parvula ). First, we used natural and playback-simulated foraging displacements to demonstrate that bystanders take notice of the vocalisations produced during such within-group conflict events but that they do not engage in any immediate post-conflict affiliative behaviour with the protagonists or other bystanders. We then used another playback experiment to assess delayed effects of within-group conflict on grooming interactions: we examined affiliative behaviour at the evening sleeping burrow, 30–60 min after the most recent simulated foraging displacement. Overall, fewer individuals groomed on evenings following an afternoon of simulated conflict, but those that did groomed more than on control evenings. Subordinate bystanders groomed with the simulated aggressor significantly less, and groomed more with one another, on conflict compared to control evenings. Our study provides experimental evidence that dwarf mongooses acoustically obtain information about within-group contests (including protagonist identity), retain that information, and use it to inform conflict-management decisions with a temporal delay.

Article activity feed

  1. Version published to 10.7554/elife.69196 on eLife
  2. eLife

    Evaluation Summary:

    This article will be of interest to behavioural ecologists studying aggression, within-group conflict, communication, and the use of social information. The study elegantly combines well-designed experiments with field observations to investigate the effects of within-group conflict on social behaviour. Specifically, it expands our understanding of social dynamics in group-living species by providing evidence that bystanders of within-group conflict may play a role in maintaining group cohesion. The findings provide a valuable contribution, and contrast, to existing work in this field.

    (This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 agreed to share their name with the authors.)

  3. eLife

    Reviewer #1 (Public Review):

    The authors explore a gap in knowledge pertaining to the non-immediate effects of intragroup interactions on individual behaviour. The main strength of this research is analysing both natural and simulated situations to demonstrate behavioural patterns to suggest that interactions between individuals may have long-lasting effects on an entire social group. The manuscript could improve by better highlighting the significance of their specific findings in a broader context. For instance, more discussion into the implications of delayed responses to intragroup conflict are desired, and a more in-depth introduction of the relationship between conflict bystanders and conflict resolution would be ideal. The authors achieve their goal of understanding the immediate and non-immediate effects of intragroup conflict on dwarf mongoose, however the conclusions can be expanded to enhance the significance of this research in relation to broader literature. This work will encourage others to consider multiple antecedents when observing behaviour, including those occurring hours beforehand. I believe that this research is significant and unique, however the emphasis of the novelty of these findings could be enhanced throughout the manuscript.

  4. eLife

    Reviewer #2 (Public Review):

    Morris-Drake et al. investigate the effect of within-group conflict on behaviour of bystanders in wild dwarf mongooses (Helogale parvula). They test whether hearing a foraging displacement between a dominant and subordinate in the social group changes the behaviour of bystanders in both the immediate and longer term, using both natural occurrences of foraging displacements, and playbacks of displacement calls to experimentally simulate conflict. They show that bystanders are more vigilant immediately following natural and simulated conflict, but that there is no change in bystanders' affiliative behaviour (measured by grooming) in the minutes after conflict. By contrast, they find that, overall, occurrences of grooming decrease in the evening following conflict but that there are contrasting patterns of grooming between certain individuals within the social group: aggressors are groomed by bystanders less, but bystanders groom each other more. Together, these data are presented as evidence that information about within-group conflict is obtained through displacement calls, and that this information is used by bystanders to shape social interactions even some time after the occurrence of conflict.

    Strengths:

    1)The study's aim to test whether there are delayed effects of within-group conflict is novel and the finding that aggressive interactions between social partners can affect the behaviour of fellow group members for some time after provides evidence that within-group conflict can have effects on social behaviour over varying temporal scales.

    1. The use of acoustic stimuli to simulate within-group conflict is novel and provides a new angle to previous work on this topic. The indication from the study that individual identity can be obtained from these acoustic calls, and that the information can be used at a later time to inform social interactions between bystanders and protagonists or victims is interesting and adds to a growing body of evidence that acoustic information can play a strong role in shaping social behaviour.

    2. The combination of natural observations and experimental simulation of within-group conflict, in the form of foraging displacements, provides a systematic examination of the effects of within-group conflict on affiliative behaviour. Experiments and natural observations comprise pair-matched treatment and controls which provide a robust test. The effort of performing such rigorous experiments on a wild population is highly commended and the neat experimental design goes some way to countering the lack of statistical power that the study is exposed to from small sample sizes.

    Weaknesses:

    1. The modelling framework used in some statistical analyses is not the most appropriate given the nature of the data.

    2. The difference in the context of post-conflict behaviour in the immediate (during foraging) and the longer term (during resting) is not really acknowledged in the interpretation of the results. While this does not affect the interpretation of evidence of delayed post-conflict increases in affiliation (grooming), there could be an argument that it would not be possible to detect changes in affiliation immediately following conflict because grooming behaviour is not observed during foraging and therefore does not represent the most suitable metric of affiliation in this context.

    3. The study finds increased vigilance in the minutes following both natural and simulated occurrences of foraging displacement but this result is not given much attention in the discussion of the results. Vigilance was not measured in the hours following simulated conflict, as grooming behaviour is, and so there is no test of whether there is a delayed change in avoidance behaviour in the same way as there is a delayed change in affiliative behaviour.

    4. Some claims for evidence for delayed post-conflict management are a little overstated given the small sample sizes in the study.

  5. Version published to 10.1101/2021.05.02.442338v1 on bioRxiv