Comment on “Consistency of fish‐shoal social network structure under laboratory conditions (Gaffney & Webster, 2018)”

Abstract

Funding information Alexander von Humboldt-Stiftung; Association for the Study of Animal Behaviour; Biotechnology and Biological Sciences Research Council; Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Zukunftskolleg Sociality is an omnipresent feature in the animal kingdom, ranging from loose aggregations of animals and fission-fusion systems to highly stable groups of related individuals. While much work on the topic has focused on understanding the emergence of group-level properties, relatively little is known about the variability among groups and about collective dynamics and structure at the community level. In a recent issue of this journal, Gaffney and Webster (2018) present some simple yet neat experiments with shoals of three-spined stickleback Gasterosteus aculeatus L. 1758 that, although perhaps a bit limited in terms of the size and number of groups tested, present some promising insights into social network characteristics at the dyadic and community level. Gaffney and Webster (2018) looked at fission-fusion characteristics by recording the number and distribution of smaller groups when shoals split. They found that, at the dyadic level, pairwise association

Reply to Jolles (2018): Comment on “Consistency of fish‐shoal social network structure under laboratory conditions (Gaffney & Webster, 2018)”

“…An unanticipated finding arising from this work was that many of the measured network metrics tended to remain consistent within groups across observations. In his recent commentary, Jolles () highlights the concordance between our finding of consistency of social network metrics and of his measures of collective motion (Jolles et al . ), with both studies dealing with functional and mechanistic aspects of grouping behaviour that probably influence one another.…”

“…As Jolles () identifies, we were unable to account for any effects of individual characteristics in shaping the social interactions recorded in our study, since these were not measured (or else were controlled for). Local assortment within shoals can arise through active shoaling preferences, such as preferences for familiar or similarly‐sized individuals, as well as passively due to differences in factors including swimming speed and sociability, as shown by Jolles et al .…”

“…), with both studies dealing with functional and mechanistic aspects of grouping behaviour that probably influence one another. Jolles () goes on to suggest how these approaches might be used to further explore fish shoal social organisation. We thank Jolles () for his comments and endorse his suggestions, adding a few of our own in this response.…”

“…Jolles () goes on to suggest how these approaches might be used to further explore fish shoal social organisation. We thank Jolles () for his comments and endorse his suggestions, adding a few of our own in this response.…”

“…Reply to Jolles (2018): Comment on "Consistency of fish-shoal social network structure under laboratory conditions In a paper this year we presented a series of experiments in which we investigated the effects of arena size and inter-observation duration upon basic social network structure metrics and related measures for shoals of threespine sticklebacks Gasterosteus aculeatus L. 1758. We were motivated to perform this experiment by the question of whether such measurements can meaningfully be compared between experiments run by different researchers and under different conditions.…”