Nocturnal selective pressures on the evolution of human musicality as a missing piece of the adaptationist puzzle

Abstract

Human musicality exhibits the necessary hallmarks for biological adaptations. Evolutionary explanations focus on recurrent adaptive problems that human musicality possibly solved in ancestral environments, such as mate selection and competition, social bonding/cohesion and social grooming, perceptual and motor skill development, conflict reduction, safe time-passing, transgenerational communication, mood regulation and synchronization, and credible signaling of coalition and territorial/predator defense. Although not mutually exclusive, these different hypotheses are still not conceptually integrated nor clearly derived from independent principles. I propose The Nocturnal Evolution of Human Musicality and Performativity Theory in which the night-time is the missing piece of the adaptationist puzzle of human musicality and performing arts. The expansion of nocturnal activities throughout human evolution, which is tied to tree-to-ground sleep transition and habitual use of fire, might help (i) explain the evolution of musicality from independent principles, (ii) explain various seemingly unrelated music features and functions, and (iii) integrate many ancestral adaptive values proposed. The expansion into the nocturnal niche posed recurrent ancestral adaptive challenges/opportunities: lack of luminosity, regrouping to cook before sleep, imminent dangerousness, low temperatures, peak tiredness, and concealment of identity. These crucial night-time features might have selected evening-oriented individuals who were prone to acoustic communication, more alert and imaginative, gregarious, risk-taking and novelty-seeking, prone to anxiety modulation, hedonistic, promiscuous, and disinhibited. Those night-time selected dispositions may have converged and enhanced protomusicality into human musicality by facilitating it to assume many survival- and reproduction-enhancing roles (social cohesion and coordination, signaling of coalitions, territorial defense, antipredatorial defense, knowledge transference, safe passage of time, children lullabies, and sexual selection) that are correspondent to the co-occurring night-time adaptive challenges/opportunities. The nocturnal dynamic may help explain musical features (sound, loudness, repetitiveness, call and response, song, elaboration/virtuosity, and duetting/chorusing). Across vertebrates, acoustic communication mostly occurs in nocturnal species. The eveningness chronotype is common among musicians and composers. Adolescents, who are the most evening-oriented humans, enjoy more music. Contemporary tribal nocturnal activities around the campfire involve eating, singing/dancing, storytelling, and rituals. I discuss the nocturnal integration of musicality’s many roles and conclude that musicality is probably a multifunctional mental adaptation that evolved along with the night-time adaptive landscape.

Globally, songs and instrumental melodies are slower and higher and use more stable pitches than speech: A Registered Report

“…The exploratory analysis of additional features can also be interpreted from the same viewpoint that extra potential differentiating features also function to enhance the saliency of pitch information: Use of longer acoustic phrases, greater sound pressure, and less noisy sounds may ease the intelligibility of pitch information. This increased loudness and salience might also support evolutionary propositions that music evolved as a mnemonic device ( 88 ) or as a night-time, long-distance communication device ( 89 ). The lyrics of the chosen songs frequently mention “night,” “moon,” “sleep,” and “love,” which may further support the nocturnal hypothesis ( 89 ).…”

“…This increased loudness and salience might also support evolutionary propositions that music evolved as a mnemonic device ( 88 ) or as a night-time, long-distance communication device ( 89 ). The lyrics of the chosen songs frequently mention “night,” “moon,” “sleep,” and “love,” which may further support the nocturnal hypothesis ( 89 ). On the other hand, similar timbral brightness, pitch interval size, and pitch range between song and speech may be due to motor and mechanistic constraints, similar to the difficulty of rapid transitioning to distant pitches caused by the limiting control capacity of tension in the vocal folds.…”

How music-induced emotions affect sexual attraction: evolutionary implications

“…The mutual mate choice model, which argues that sexual dimorphism is low among humans, although some sex differences remain, may help explain these results ( Miller, 2013 ). Thus, the absence of significant sex differences in basic music perception skills ( Bertolo et al, 2023 ) does not provide convincing evidence against sexual selection, since both sexes need to be able to perceive and evaluate aesthetic displays ( Miller, 2001 ; Varella, 2023 ). In general, the current empirical evidence seems to be in line with Darwin (1871) , who did not regard music as a sexual dimorphic trait.…”

Love songs and serenades: a theoretical review of music and romantic relationships

“…Even in a species of duck, for which female mate choice seems more important, both partners need to be able to complete a head-bobbing courtship ritual (a kind of head-banging partner dance), and thus both sexes possess the required coordination abilities ( Silberstein, 1983 ). In species with mutual mate choice, such as humans, both sexes need to be able to perceive and evaluate esthetic displays, so less sexual dimorphism would be expected ( Miller, 2001 ; Varella, 2023 ). As Leongómez et al (2022) point out, sex differences could be highly contextual, and may only exist in specific mating behavior, not in general ability.…”