The social nature of consonant sounds. Insights from chicks

Do we like consonant sounds before any exposure to music? One hypothesis is that consonant sounds represent biological determinants in agents’ identification: consonant ratios are predominant in human vocalizations and, when in agreement, people produce consonant utterances in dyadic conversations. Consonance seems also a cue we are predisposed to attend to: human newborns readily show neural circuits to encode consonance as different from dissonance. However, only data from completely naïve organisms could disentangle whether consonant sounds have an innate biological value. In a previous study, the young of the domestic fowl (Gallus gallus) showed to prefer consonant sounds. Here, with the aim at investigating the reason for such preference, we analyzed the ratio of fundamental frequencies between specific points in the spectrogram of four different types of positive/negative valenced calls and we quantified the frequency of consonant/dissonant intervals. Consonant ratios prevailed in chicks’ calls and this was true also for fear thrills, thus fueling the idea that consonant sounds are biologically relevant, likely facilitating the detection of an organism. In sum, there would be a highly social component in consonant organization of sounds that has nothing to do with experience.