Early maternal care predicts reliance on social learning about food in adult rats

Abstract

Many vertebrates rely extensively on social information, but the value of information produced by other individuals will vary across contexts and habitats. Social learning may thus be optimized by the use of developmental or current cues to determine its likely value. Here, we show that a developmental cue, early maternal care, correlates with social learning propensities in adult rodents. The maternal behavior of rats Rattus norvegicus with their litters was scored over the first 6 days postpartum. Rat dams show consistent individual differences in the rate they lick and groom (LG) pups, allowing them to be categorized as high, low, or mid-LG mothers. The 100-day old male offspring of high and low-LG mothers were given the opportunity to learn food preferences for novel diets from conspecifics that had previously eaten these diets ("demonstrators"). Offspring of high-LG mothers socially learned food preferences, but offspring of low-LG mothers did not. We administered oxytocin to subjects to address the hypothesis that it would increase the propensity for social learning, but there were no detectable effects. Our data raise the possibility that social learning propensities may be both relatively stable throughout life and part of a suite of traits "adaptively programmed" by early developmental experiences.

Not-so-social learning strategies

“…Therefore, across the full range of conditions that might be thought to induce dissatisfaction or uncertainty, these intuitive, folk psychological labels may provide poor predictors of the magnitude of social learning effects. Illustrating this point, Lindeyer et al [12] recently found that, in adulthood, rats that had received relatively little licking and grooming from their mothers (low LG) showed weaker socially enhanced food preferences than rats that had received more licking and grooming (high LG). As the authors pointed out, previous research has indicated that low-LG rats are more risk-sensitive and anxious-at an intuitive level, they are more 'uncertain'-than high-LG rats.…”

The Evolution of Individual and Cultural Variation in Social Learning

“…Three studies, all with rats, show that maternal 142 deprivation or markers of high maternal stress (infrequent licking and grooming) reduce the 143 subsequent social learning of food preferences from unfamiliar demonstrators [52][53][54]. This 144 facultative switching in response to specific developmental cues might represent an adaptively 145 limited degree of phenotypic plasticity: maternal deprivation or stress might indicate a recent 146 environmental shift to which mothers are poorly suited, making it adaptive to rely less on others' 147 potentially out-dated knowledge (although see [55] for caution regarding anticipatory parental 148 effects).…”

Cultural Evolution: A Review of Theory, Findings and Controversies

“…Recent studies have shown that social learning in rats can be influenced by early developmental cues such as maternal care (Lindeyer et al 2013), and in bees by past learning histories (Dawson et al 2013). However, while similar processes may well operate in humans (Heyes 2012), it is difficult to explain the species differences in cumulative cultural evolution described above without positing some kind of genetic adaptation in the human lineage, perhaps involving the extent of imitation during childhood (Lyons et al 2007) or theory of mind (Tomasello et al 2005).…”