In order to investigate cross-cultural variation in systems of conversational turn-taking (who speaks and when), the researchers analyze the association of various contextual, verbal, and non-verbal factors with mean response time. Despite some variation in response time between languages, each of the explanatory variables is found to have significant impact on response time independent of language. A further test on subjective perception of ideal response time suggests that although similar factors act on response patterns cross-culturally (in support of a 'universal systems' theory), speakers are hypersensitive to even minor cultural variations in response time.

In order to investigate cross-cultural variation in systems of conversational turn-taking (who speaks and when), the researchers analyze the association of various contextual, verbal, and non-verbal factors with mean response time. Despite some variation in response time between languages, each of the explanatory variables is found to have significant impact on response time independent of language. A further test on subjective perception of ideal response time suggests that although similar factors act on response patterns cross-culturally (in support of a 'universal systems' theory), speakers are hypersensitive to even minor cultural variations in response time.

In the field of bioacoustics, the Acoustic Adaptation theory suggests that variation in vocalization across different species can be accounted for by the acoustic properties of different habitats. Here, the researchers test consonant- and vowel-heaviness in human languages against various environmental variables in order to examine the theory's potential application to our own species. The authors identify a significant negative correlation between consonant heaviness and temperature, precipitation, and tree cover, and some positive correlation with rugosity and elevation as their most important findings, while acknowledging the potentially influential roles of migration and demographic factors in producing this relationship.

Stark attempts to resituate Tylor's formulation of religion by calling into question Swanson's (1960) and Peregrine's (1996) findings that supernatural sanctions and moral behavior are consistently correlated in small-scale societies. Positing that Swanson's correlations were confounded by variables related to cultural complexity, Stark tests the association of presence of moralizing Gods with cultural complexity explicitly, as well as measures of morality in various nations as provided by the World Values Survey (1990-1991). The robust correlations across cultures noted below, as well as cross-national findings, provide support for the researcher's theory that it is particular conceptions of God rather than participation in rites and rituals which empower religion to sustain complex moral culture.

The 'obstetrical dilemma' postulates that human females evolved a pelvis shape that was a compromise between the needs of bipedal locomotion and the need for a wider pelvic opening. The implication is that the female pelvis should be similar across the world. Researchers examine the size and shape of the birth canal of female individuals in the Goldman and Human Origin datasets. Contrary to the 'obstetrical dilemma,' the findings reveal that there is indeed significant geographical variation in size and shape of the female birth canal. Neutral evolutionary processes, particularly genetic drift, were suggested to be influential in female canal shape whereas the predicted effects of climate on canal diversity were only minimal.

The 'obstetrical dilemma' postulates that human females evolved a pelvis shape that was a compromise between the needs of bipedal locomotion and the need for a wider pelvic opening. The implication is that the female pelvis should be similar across the world. Researchers examine the size and shape of the birth canal of female individuals in the Goldman and Human Origin datasets. Contrary to the 'obstetrical dilemma,' the findings reveal that there is indeed significant geographical variation in size and shape of the female birth canal. Neutral evolutionary processes, particularly genetic drift, were suggested to be influential in female canal shape whereas the predicted effects of climate on canal diversity were only minimal.

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.

This study seeks correlations between social variables and linguistic variables, including the following ten speech patterns: repetitiveness, long-windedness, drawl, charm and variability, amount of pausing, sharing of air time, tension, noisy qualities, breath control, and forcefulness. Many associations are discussed, particularly those involving societal complexity, sex roles, and singing and dancing.

How do subsystems of language evolve over time? It is commonly assumed that grammatical changes of language are slower than vocabulary changes. Using a Dirichlet process mixture model to analyze rates of language evolution in 81 Austronesian languages, the authors find that to the contrary, the grammatical features of language tend to change at a faster rate than basic vocabulary. Furthermore, their results show that grammatical features have higher rates of homoplasy, more frequent contact-induced change, and less deliberate differentiation than basic vocabulary.

Using experimental methods, these researchers evaluated the function of pride in ten small-scale societies by testing personal pride’s association with valuation by the surrounding community. Their aim was to see if findings from western(-ized), educated, industrialized, rich, and democratic (WEIRD) societies replicate in non-WEIRD societies. Simple linear regression in each society indicates that the amount of pride one feels for a given action closely matches how highly others in the same community value the action. Authors conclude support for the universality of the pride system.