Challenges of mismatching timescales in longitudinal studies of collective behaviour

Abstract

How individuals’ prior experience and population evolutionary history shape emergent patterns in animal collectives remains a major gap in the study of collective behaviour. One reason for this is that the processes that can shape individual contributions to collective actions can happen over very different timescales from each other and from the collective actions themselves, resulting in mismatched timescales. For example, a preference to move towards a specific patch might arise from phenotype, memory or physiological state. Although providing critical context to collective actions, bridging different timescales remains conceptually and methodologically challenging. Here, we briefly outline some of these challenges, and discuss existing approaches that have already generated insights into the factors shaping individual contributions in animal collectives. We then explore a case study of mismatching timescales—defining relevant group membership—by combining fine-scaled GPS tracking data and daily field census data from a wild population of vulturine guineafowl ( Acryllium vulturinum ). We show that applying different temporal definitions can produce different assignments of individuals into groups. These assignments can then have consequences when determining individuals' social history, and thus the conclusions we might draw on the impacts of the social environment on collective actions. This article is part of a discussion meeting issue ‘Collective behaviour through time’.

A multi-scale review of the dynamics of collective behaviour: from rapid responses to ontogeny and evolution

“…[ 174 ] and Ogino et al . [ 175 ] both analyse metrics of collective behaviour at a range of timescales, and demonstrate that the conclusions drawn are dependent on the timescale chosen for analysis. Romero-Ferrero et al .…”

“…While there is great potential in studying collective behaviour over developmental and evolutionary timescales, there are substantial challenges comparing behaviours across time and species. The contributions to the special issue by Sridhar et al [174] and Ogino et al [175] both analyse metrics of collective behaviour at a range of timescales, and demonstrate that the conclusions drawn are dependent on the timescale chosen for analysis. Romero-Ferrero et al [176] develop new analytical tools to track how information can flow among members of the same group.…”

Breeding alters females’ social positions by changing dominance dynamics

“…Subtle variation in dyadic interaction rates among group members could therefore influence hierarchy inference. We tested this using agent-based models as follows: 1) Generate a group comprising 16 males and 10 females, emulating sex ratios and group sizes seen in vulturine guineafowl [22,48]. 2) Assign individuals a dominance value (representing all determinants of dominance in one value) from two normal distributions, such that males are dominant over all females, and assign females’ ‘real hierarchy positions’ as the order of their dominance values (for subsequent comparisons with their estimated hierarchy positions). 3) Randomly assign 50% of females as ‘breeding’ and 50% as ‘non-breeding’. 4) Simulate outcomes of dyadic dominance interactions via a probabilistic approach based on interacting individuals’ relative dominance values and a hierarchy steepness parameter.…”

“…1) Generate a group comprising 16 males and 10 females, emulating sex ratios and group sizes seen in vulturine guineafowl [22,48].…”

Group-level differences in social network structure remain repeatable after accounting for environmental drivers

“…While during the pre-breeding season colonies contained a mix of familiar (within sex) and unfamiliar (between sex) individuals, familiarity was more uniform in post-breeding seasons (as all birds had been together for at least three months). Thus, we analysed these two seasons independently, allowing us to ensure that our findings are robust to colony history (which can also drive differences in behaviours among groups; [31,32]). ) and we had four colonies for year.…”