The rise and fall of an arbitrary tradition: an experiment with wild meerkats

Abstract

Humans often follow the choices of others, even when profitable alternatives exist, leading to the maintenance of arbitrary traditions. Arbitrary traditions have also been shown to persist in captive groups of other animals, but it is unclear whether they do so in the wild where there are ample opportunities for exploring alternatives. We conducted the first experiment examining the maintenance of arbitrary traditions in wild mammal groups. We trained 'demonstrators' in seven meerkat groups to obtain rewards from one out of the two distinctive landmarks. Two control groups had no trained demonstrators. Naive individuals initially ignored the landmarks, but were more likely to approach them and obtain rewards following encounters with demonstrators. Individuals in control groups were less likely to obtain rewards. While control groups showed no landmark preference, experimental groups initially preferred the landmark chosen by demonstrators, even though an equally rewarding alternative was nearby, leading to the establishment of local traditions. However, individuals that learned that one landmark was profitable began to explore the other rather than conforming to the majority behaviour, so traditions collapsed over time. This suggests that where conformist tendencies are lacking, the maintenance of traditions in natural populations depends on the relative influence of social and individual learning.

Individual variation in cognitive performance: developmental and evolutionary perspectives

“…There may also be instances in which the relative comfort and lack of risk in captivity may result in artificially elevated results. For example, the presence of abundant food and lack of predation pressure may facilitate the persistence of arbitrary, socially learned traditions [26] and promote the manufacture and use of tools in normally non-tool using species [27,28]. Impressive feats by captive animals may be the manifestation of cognitive abilities latent in their wild counterparts, but unless we understand the developmental inputs necessary for such abilities to be expressed, we cannot begin to unravel how they evolved.…”

Social learning and the development of individual and group behaviour in mammal societies

“…Where low-cost opportunities for individual learning are readily available, socially learned traditions are unlikely to persist (see also [72 -75]). This is illustrated by a second experiment, which examined whether naive meerkats would adopt the preferences of demonstrators trained to obtain rewards from one of two adjacent and equally rewarding landmarks of distinctive shape and colour [76]. Here, social learning promoted an initial bias towards the landmark used by demonstrators, generating arbitrary traditions within groups.…”

Experimental identification of social learning in wild animals

“…Using two artificially created landmarks and trained demonstrators exhibiting a preference for one over the other, Thornton and Malapert (2009) examined the transmission of foraging patch preferences in wild meerkats. Individual demonstrators were trained to associate food rewards with one of two locations marked by distinctive landmarks, and they had subsequent opportunities to perform their choices in front of, and be joined at the landmarks by, naive members of their group.…”