Familiarity affects social network structure and discovery of prey patch locations in foraging stickleback shoals

Abstract

Numerous factors affect the fine-scale social structure of animal groups, but it is unclear how important such factors are in determining how individuals encounter resources. Familiarity affects shoal choice and structure in many social fishes. Here, we show that familiarity between shoal members of sticklebacks (Gasterosteus aculeatus) affects both fine-scale social organization and the discovery of resources. Social network analysis revealed that sticklebacks remained closer to familiar than to unfamiliar individuals within the same shoal. Network-based diffusion analysis revealed that there was a strong untransmitted social effect on patch discovery, with individuals tending to discover a task sooner if a familiar individual from their group had previously done so than if an unfamiliar fish had done so. However, in contrast to the effect of familiarity, the frequency with which individuals had previously associated with one another had no effect upon the likelihood of prey patch discovery. This may have been due to the influence of fish on one another's movements; the effect of familiarity on discovery of an empty ‘control’ patch was as strong as for discovery of an actual prey patch. Our results demonstrate that factors affecting fine-scale social interactions can also influence how individuals encounter and exploit resources.

How social network structure affects decision-making inDrosophila melanogaster

“…At the group level, the social environment, and the social structure that follows, may greatly affect the way social information spreads among individuals [11,12]. Social network structures have been found to vary across and within species, and are sensitive to environmental factors [13].…”

Social dynamics, network structure, and information diffusion in fish shoals.

“…NBDA can be based on either the order in which individuals acquired the trait or the actual times of acquisition. These models can be used to compare strength of social transmission between contexts (e.g., open vs complex environments: Webster et al, 2013) or to test hypotheses related to different social learning strategies thought to be at work in a population (e.g., copying familiar individuals: Atton et al, 2014;vertical transmission: Allen et al, 2013). Factors predicted to influence asocial rates of acquisition, such as neophobia or boldness, can also be incorporated into the models to control for their effects (Hoppitt, Boogert, et al, 2010).…”

“…While still a new technique, NBDA has already been employed in both laboratory and field studies on a number of species, including: three-spined sticklebacks (Gasterosteus aculeatus) (Atton et al, 2012;Webster et al, 2013;Atton et al, 2014), multiple species of Paridae songbirds (Aplin et al, 2012;Aplin et al, 2015), ring-tailed lemurs (Lemur catta) , red-fronted lemurs (Eulemur rufifrons) (Schnoell & Fichtel, 2012), and humpback whales (Megaptera novaeangliae) (Allen et al, 2013). So far NBDA has been used primarily to study the spread of foraging information related to locating and accessing food, but it has the potential to address nearly any behaviorally transmitted trait-e.g., vocal traditions in cetaceans (Noad et al, 2000), mate-choice copying (Dugatkin, 1992), or defensive behaviors (Magurran & Higham, 1988;Mineka & Cook, 1988).…”

“…For example, Atton et al (2014) found that familiarity between two sticklebacks (G. aculeatus) facilitated discovery of a novel food source. The pattern of information acquisition in shoals made up of both familiar and unfamiliar fish was best described by a network allowing information flow only between familiar individuals; these results are largely consistent with a social learning strategy of "copy familiar individuals" (Galef, 2009).…”

“…Across a wide variety of taxa, familiarity has been shown to influence social preferences, including in fish (Griffiths & Magurran, 1997;Atton et al, 2014), birds (Kohn et al, 2015), and mammals (Keller et al, 2011). Familiarity can arise through learned recognition of specific individuals (Griffiths & Magurran, 1997;Ward et al, 2009), as well as via mechanisms that facilitate a more general recognition of particular classes of individual.…”