Evolutionary musicology is a subfield of biomusicology that grounds the cognitive mechanisms of music appreciation and music creation in evolutionary theory. It covers vocal communication in other animals, theories of the evolution of human music, and holocultural universals in musical ability and processing.
History
The origins of the field can be traced back to Charles Darwin who wrote in The Descent of Man, and Selection in Relation to Sex:
This theory of a musical protolanguage has been revived and re-discovered repeatedly.
The origins of music
Like the origin of language, the origin of music has been a topic for speculation and debate for centuries. Leading theories include Darwin's theory of partner choice (women choose male partners based on musical displays), the idea that human musical behaviors are primarily based on behaviors of other animals (see zoomusicology), the idea that music emerged because it promotes social cohesion, the idea that music emerged because it helps children acquire verbal, social, and motor skills, and the idea that musical sound and movement patterns, and links between music, religion and spirituality, originated in prenatal psychology and mother-infant attachment.
Two major topics for any subfield of evolutionary psychology are the adaptive function (if any) and phylogenetic history of the mechanism or behavior of interest including when music arose in human ancestry and from what ancestral traits it developed. Current debate addresses each of these.
One part of the adaptive function question is whether music constitutes an evolutionary adaptation or exaptation (i.e. by-product of evolution). Steven Pinker, in his book How the Mind Works, for example, argues that music is merely "auditory cheesecake"—it was evolutionarily adaptive to have a preference for fat and sugar but cheesecake did not play a role in that selection process. This view has been directly countered by numerous music researchers.
Adaptation, on the other hand, is highlighted in hypotheses such as the one by Edward Hagen and Gregory Bryant which posits that human music evolved from animal territorial signals, eventually becoming a method of signaling a group's social cohesion to other groups for the purposes of making beneficial multi-group alliances.
The bipedalism hypothesis
The evolutionary switch to bipedalism may have influenced the origins of music. The background is that noise of locomotion and ventilation may mask critical auditory information. Human locomotion is likely to produce more predictable sounds than those of non-human primates. Predictable locomotion sounds may have improved our capacity of entrainment to external rhythms and to feel the beat in music. A sense of rhythm could aid the brain in distinguishing among sounds arising from discrete sources and also help individuals to synchronize their movements with one another. Synchronization of group movement may improve perception by providing periods of relative silence and by facilitating auditory processing. The adaptive value of such skills to early human ancestors may have been keener detection of prey or stalkers and enhanced communication. Thus, bipedal walking may have influenced the development of entrainment in humans and thereby the evolution of rhythmic abilities. Primitive hominids lived and moved around in small groups. The noise generated by the locomotion of two or more individuals can result in a complicated mix of footsteps, breathing, movements against vegetation, echoes, etc. The ability to perceive differences in pitch, rhythm, and harmonies, i.e. "musicality", could help the brain to distinguish among sounds arising from discrete sources, and also help the individual to synchronize movements with the group. Endurance and an interest in listening might, for the same reasons, have been associated with survival advantages eventually resulting in adaptive selection for rhythmic and musical abilities and reinforcement of such abilities. Listening to music seems to stimulate release of dopamine. Rhythmic group locomotion combined with attentive listening in nature may have resulted in reinforcement through dopamine release. A primarily survival-based behavior may eventually have attained similarities to dance and music, due to such reinforcement mechanisms . Since music may facilitate social cohesion, improve group effort, reduce conflict, facilitate perceptual and motor skill development, and improve trans-generational communication, music-like behavior may at some stage have become incorporated into human culture.