By testing relationships between musical, geographic, genetic, and linguistic distance among nine indigenous groups in Taiwan, the researchers aim to quantitatively evaluate a developing theory of coevolution between these traits. An especially strong correlation between musical variability and genetic distance suggests that music may possess worldwide time depth, diversity, and universality equal to or greater than that of language, and could thus serve as a complementary marker for reconstruction of long-term population shifts.

In asking whether or not there are meaningful universals in music, researchers compiled two catalogs – the Natural History of Song (NHS) Ethnography which contains ethnographic descriptions of song performances collected from eHRAF World Cultures, and the NHS Discography, which contains field recordings of performances of dance, healing, love, and lullaby. Using these two corpora, the study tests a variety of hypotheses about the universality and variability of both music behavior and music form. Specifically, whether there are meaningful universals in meaning and sound. The catalog of published sound recordings was analyzed by machine summaries, listener ratings, and manual transcriptions, which revealed that there were identifiable features of songs which could then predict their primary function cross-culturally. The results as a whole revealed that the existence of music is a cultural universal, and that the variation within music can be characterized by three factors assessing the formality, arousal, and religiosity of the song events. They also found that musical behavior varies more within societies than between them.

This chapter examines the relationship between social cohesion (measured using variables like subsistence type, stable work teams, and settlement patterns) and musical cohesion. All hypotheses are supported.

Inter-group variation is greater in humans than in any other animal, and scholars continue to debate the cause of this diversity. Two competing explanatory models of human variation emphasize either (1) ecological differences and "evoked" culture or (2) population-level effects of cultural transmission. The former emphasizes mechanisms that operate within a single generation, while the latter emphasizes cumulative cultural history operating over many generations. To test these competing models, the authors measured the relative power of ecological variables as compared to culture history to predict behavioral variation in 172 western North American tribes. Culture history is subdivided into culture phylogeny (based on language phylogeny) and spatial distance.

This paper examines the enormous variation in linguistic diversity among Pacific Islands by testing its relationship with various environmental variables put forth in several common theories of language richness. The researchers identify variables relating to land area and island isolation as accounting for about half of variation in linguistic diversity, suggesting that the other half is a result of complex social factors.

This article re-examines previous hypotheses by Tylor regarding kin avoidance behavior. The author tests hypotheses on a sample of North American societies that accounts for genetic language families. Results provide partial support for hypotheses.

A large-scale comparative study of folk songs around the world employing systematic measures (cantometrics). The aim was not just to describe variation but to test hypotheses about the relationships between song style and societal structures. Dance was also considered.

The author reanalyzes hypotheses proposed by Lomax et al. (1968) that are based on Lomax's collection of cantometric data. Considering historical/regional variables, the author suggests that difusion and common history better explain certain musical features such as wordiness than functional and evolutionary processes. However, other Lomax findings are supported involving interlocked, contrapuntal singing and narrow nasal-voiced singing.

Several theories on the development of matrilocal residence are tested. The main argument put forth predicts that matrilocal residence will develop in response to a need to break up fraternal interest groups that encourage internal war and instead encourage a pattern of external war that is more beneficial in populated regions with additional group migration.

The researchers utilize a GIS approach in order to examine the relationship between global linguistic distribution and various cultural and environmental factors. The resulting positive association between political complexity and both latitude and language range leads the researchers to propose that large, politically complex entities exert a homogenizing pressure on language. However, the causal link may also be in the other direction, with possession of common language facilitating the creation of more complex political institutions.