Transmission of walnut-feeding skills from mother to young in wood mice (Apodemus speciosus)

Mammalian feeding behavior is often acquired or improved by learning. Social learners are thought to attain novel information or skills faster and at lower cost than asocial learners. In this study, we examined what types of learning affect the acquisition of efficient feeding behavior by the wood mouse Apodemus speciosus when feeding on large, hard-shelled walnuts. In house cages, naïve mice acquired an efficient feeding manner during the 14-day conditioning to walnuts, suggesting individual trial-and-error learning contributes to their feeding skills. Social factors such as learning from walnuts that have been opened by other individuals or by observing walnut consumption by proficient conspecifics did not affect the rate of acquisition of efficient feeding. However, weaned offspring could eat walnuts more efficiently and frequently if the mother had been given walnuts during her rearing period. Thus, the skill is likely transmitted between the mother and offspring in addition to individual self-learning.