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.

Reputations are an important aspect of human social interactions and cooperation, but much of the research on reputations has focused on a narrow range of domains such as prosociality and aggressiveness. This study aims to provide an empirical view of reputation domains across different cultures by analyzing ethnographic texts on reputations from 153 cultures. The findings suggest that reputational domains vary across cultures, with reputations for cultural conformity, prosociality, social status, and neural capital being widespread. Reputation domains are more variable for males than females, and certain reputation domains are interrelated. The study highlights the need for future research on the evolution of cooperation and human sociality to consider a wider range of reputation domains and their variability across different social and ecological contexts and genders.

This paper discusses a cross-cultural study comparing features of grammatical structure and features of social structure. The author hypothesizes that the language will emphasize "self" with more personal protection within a society.

This article explores the possible relationship between the cultural evolution of language, music, and genetic variation beyond the level of language families. Due to their linguistic diversity, the authors use a sample of 14 Northeast Asian societies with matching information on their music, genetics, and linguistic patterns. The variables measuring language are lexicon, phonology, and grammar. Then, the authors compare each variable's relationship to music and genetic variation. The results only show a significant correlation between grammar and genetic variation.

Is grammatical complexity shaped by sociodemographic and sociolinguistic factors? The previously accepted "linguistic niche hypothesis" claims that with an increased number of nonnative speakers in a social group (high exotericity), grammatic complexity decreases; on the other hand, grammatical complexity increases amongst isolated linguistic communities (low exotericity). Through the use of spatiophylogenetic modelling of 1314 languages, the authors of this study do not find adequate evidence to support the linguistic niche hypothesis. Instead, they suggest that linguistic complexity is better predicted by phylogeny and geographic contiguity.

The authors statistically test existing theories and proposals regarding the existence and nature of the creole language profile. Results indicate that consistencies and variation between creole languages, as with non-creole languages, is a result of genealogical and contact processes. However, creole languages are unique from non-creole languages in that they have more than one language in their ancestry. Findings "call into question the existence of a pidgin stage in creole development and of creole-specific innovations." Support is found for the idea that language learning and transmission are strikingly resilient processes.

This article explores the relationship between language structure and social environment, positing that linguistic factors such as morphological complexity are associated with demographic/socio-historical factors such as number of speakers, geographic spread, and degree of language contact. Data support such an association. The authors further propose a Linguistic Niche Hypothesis suggesting that “the level of morphological specialization is a product of languages adapting to the learning constraints and the unique communicative needs of the speaker population” (7).

Authors hypothesize that grammatical sex gender may be related to social structural variables. Results support this hypothesis and suggest that the degree of sex bias in the social structure is associated with the relative frequency of masculine and feminine nouns in languages with sex gender.

How is the evolution of language shaped by speaker population size? Through comparative data analyses of 153 language pairs from the Austronesian, Indo-European, and Niger-Congo language families, the authors find that the influence of population size on language evolution is not the same in the three language families. Only in Indo-European languages did a smaller population size of language-speakers significantly predict more word loss.

Using ethnography, historical linguistics, paleoanthropology, and speech biomechanics, the present study examines the relationship between labiodentals and the post-Neolithic period with the introduction of agriculture and softer diets. The results offer support for the linguist, Charles Hockett's, hypothesis that the shift in bite configuration in the post-Neolithic period, as well as the persistence of overbite and overjet, facilitates and makes the articulation of labiodentals more prevalent. Using cross-cultural comparison, findings also reveal that societies that produce their food are more likely to evolve and keep labiodentals than those that are not food-producing. Contact with other societies is also a mode by which societies gain labiodentals. Lastly, the expansion of agricultural and food processing technology over time has been imperative to labiodental articulations.