The integrative biology of marmoset monkey vocal learning

Primates exhibit a range of vocal behaviours. This range arises from species-specific developmental processes which, in turn, are shaped by evolutionary pressures. We must therefore consider that all primate species do not follow the same developmental path to their vocal behaviours. We will use marmoset monkeys as a case study for the integrative biology of vocal learning. As we will show, marmoset contact call development exhibits a pattern of socially guided vocal production learning that is like the pattern exhibited by prelinguistic human infants and the juvenile zebra finch, a songbird. This socially guided contact call development and other vocal behaviours emerge in a landscape of anatomical changes that is modulated by a large-scale neural system. Comparing their vocal developmental strategies with humans, we will then consider the possibility that the marmoset monkey's potential for infant vocal production learning may be the result of similar (convergent) evolutionary changes to their developmental timing and life history strategy. Overall, we hope that the example of marmoset monkeys presented here reveals how species differences in vocal behaviours-vocal learning, in this instance-can unfold across the different timescales of evolution, development and behaviour. This article is part of the theme issue 'Mechanisms of learning from social interaction'.