Familiarity facilitates social learning of foraging behaviour in the guppy

Abstract

Previous studies have shown that guppies, Poecilia reticulata, can learn the route to a food source by shoaling with knowledgeable conspecifics, and prefer to shoal with experienced foragers and familiar fish. We tested the hypothesis that guppies would learn more effectively from (1) familiar than unfamiliar demonstrators and (2) well-trained than poorly trained demonstrators. Demonstrator fish were given experience in swimming a route to a food source and then introduced into shoals of untrained observer guppies; the spread of this foraging skill was recorded over 15 trials. The demonstrators were either familiar or unfamiliar to the observers and either well trained or poorly trained. Observers performed significantly better when the demonstrators were familiar. The training of the demonstrators made no overall difference to the performance of naïve observers. However, whilst observers in shoals exposed to well-trained demonstrators did better initially than those with poorly trained ones, the latter learned the route to the feeder faster. Our results suggest that familiarity may generate a form of directed social learning in guppy shoals, in which fish learn more effectively from familiar conspecifics. An analysis of who follows whom suggests that well-trained demonstrators can provide a 'tip-off' as to the location of the hole but poorly trained demonstrators were more likely to be followed. The results suggest that while observers are able to shoal with poorly trained demonstrators, well-trained demonstrators swim the maze route too quickly to be followed, but may attract attention to the maze route.

Effective leadership and decision-making in animal groups on the move

“…However, in many cases, few individuals have pertinent information, such as knowledge about the location of a food source 3,4 , or of a migration route [5][6][7][8][9] . Using a simple model we show how information can be transferred within groups both without signalling and when group members do not know which individuals, if any, have information.…”

“…Although it is likely that some species have a genetically determined propensity to migrate in a general direction 14,15 , or respond to abiotic cues such as thermal gradients that may aid migration 16,17 , it is likely for many species that experienced group members play an important role in guiding those that are less experienced or inexperienced. Relatively few informed individuals within fish schools are known to be able to influence the foraging behaviour of the group 3 and the ability of a school to navigate towards a target 4 . Similarly, very few individuals (approximately 5%) within honeybee swarms can guide the group to a new nest site 7 .…”

“…2b). Lack of group cohesion would clearly be detrimental to honeybees [6][7][8] or obligate schooling fish 1,2,13 and there is experimental evidence that such a trade-off also occurs in other animal groups where social learning of routes depends on the ability of informed individuals to maintain social interactions with those that are naive 4 .…”

“…Groups of animals often have to make collective decisions, such as to move together to a specific resource, such as a nest site 1,5-9 or food source 2,4 . The means by which such decisions can be made is very poorly understood, especially in the case of large groups and when individuals are not capable of knowing whether they are in a majority or minority, or how the quality of their information compares with that of others, or even whether there are any other individuals in the population with information.…”

Consensus decision making in human crowds

“…In some cases, it has been shown that very few individuals within a group may actually possess information on, for example, the direction to a resource (ants, Leptothorax albipennis: Franks et al 2002; honeybees, Apis mellifera: Seeley 2003; golden shiners, Notemigonus crysoleucas (in the laboratory): Reebs 2000; guppies, Poecilia reticulata (in the laboratory) : Reader & Laland 2000;Swaney et al 2001). The simplest situation where such information differences among group members are present could be because of the different spatial positions of individuals.…”