Kinship and familiarity as factors affecting social transfer of food preferences in adult Mongolian gerbils (Meriones unguiculatus).

Abstract

Experiments were carried out with Mongolian gerbils (Meriones unguiculatus) to assess whether a socially mediated acquisition of diet selection exists in this species. Results showed that a gerbil was influenced in its diet choices by information extracted during a brief period of interaction with a familiar conspecific that had recently eaten a novel food. Data revealed that the acquisition of a food preference from a conspecific depends on the existence of a social bond between the interacting gerbils. Either genetic relatedness (being brother or sister raised in different litters) or familiarity (being bred in the same litter or being member of a reproductive pair) is necessary for the transfer of information. Unfamiliar and unrelated observer gerbils did not selectively choose their demonstrator's food.

Familiarity and relatedness: Effects on social learning about foods by Norway rats and Mongolian gerbils

“…However, unlike observer rats (Galefet aI., 1984), observer gerbils acquired flavor preferences from conspecific demonstrators only when those demonstrators were either genetically related or familiar to their observers (Valsecchi et aL, 1996). Further, even when demonstrator Mongolian gerbils and their observers were from the same litter and had been raised together, the effects of the food fed to demonstrators on the food choices of their observers were relatively short-lived.…”

“…Further, even when demonstrator Mongolian gerbils and their observers were from the same litter and had been raised together, the effects of the food fed to demonstrators on the food choices of their observers were relatively short-lived. Observer gerbils exhibited a preference for their respective demonstrators' diets for 16 but not for 24 h after the start of testing (Valsecchi et al, 1996). Valsecchi et al (1996) attributed the difference between their finding of an important impact of familiarity and relatedness on social learning in Mongolian gerbils and Galef et als (1984) failure to find such an effect in Norway rats to a difference between Norway rats and Mongolian gerbils in the relative likelihood that members of each species will behave aggressively when they first meet conspecifics that are both unfamiliar and unrelated.…”

“…Observer gerbils exhibited a preference for their respective demonstrators' diets for 16 but not for 24 h after the start of testing (Valsecchi et al, 1996). Valsecchi et al (1996) attributed the difference between their finding of an important impact of familiarity and relatedness on social learning in Mongolian gerbils and Galef et als (1984) failure to find such an effect in Norway rats to a difference between Norway rats and Mongolian gerbils in the relative likelihood that members of each species will behave aggressively when they first meet conspecifics that are both unfamiliar and unrelated. Unfamiliar/unrelated Mongolian gerbils fight when they meet for the first time, whereas the young female Norway rats that have served as subjects in most experiments on sociallearning about foods are far less likely to behave aggressively on first encounter.…”

“…The most obvious difference in how studies on social learning have been conducted when gerbils (Valsecchi et a!., 1996) rather than rats (Galef& Wigmore, 1983) have been used as subjects lies in the ways in which demonstrators of each species are fed before they interact with conspecific observers. Rat demonstrators are typically placed on a 23-h schedule offood deprivation for several days and are then fed a flavored diet for 1 h immediately before they interact with their observers.…”

“…Because it is difficult to induce Mongolian gerbils to eat unfamiliar powdered foods on a 23-h schedule of food deprivation (Choleris & Valsecchi, unpublished observation), gerbil demonstrators are typically food deprived for 16 h and then given access to a flavored powdered food for 8 h before they interact with their respective observers (Valsecchi et a!., 1996). When fed in this way, demonstrator gerbils eat only 20o/",'&ftheir days' rations in the last 2 h of the 8"h feeding period (Choleris & Valsecchi, unpublished observation).…”