Population size is generally assumed to play a pivotal role in the evolution of languages and cultures, but the expected patterns and potential mechanisms of change are unsettled. Theoretical models are limited by this uncertainty because they require making prior assumptions about language evolution. Using a sample of 20 Polynesian languages, authors test the effect of population size on the gain, loss, and total change of basic vocabulary words.

Population size is generally assumed to play a pivotal role in the evolution of languages and cultures, but the expected patterns and potential mechanisms of change are unsettled. Theoretical models are limited by this uncertainty because they require making prior assumptions about language evolution. Using a sample of 20 Polynesian languages, authors test the effect of population size on the gain, loss, and total change of basic vocabulary words.

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.

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.

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.

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.

Scholars generally agree that, across languages, the relationship between particular sounds and the meaning of words is arbitrary. In this article the authors test this assumption, seeking patterned associations between sound and meaning in the basic vocabulary lists of a large, worldwide sample of languages.

Researchers looked at four different demographic scenarios (altered mean vital rates (i.e., fertility and mortality), vital rate stochasticity, vital rate covariance, and periodic catastrophes) and their possible effects on the rapid population growth of contemporary human foragers and steady population decline of chimpanzees. They evaluated these variables and the various conditions that would favor a more sustainable zero population growth (ZPG) among 10 small-scale subsistence human populations (Agta, Ache, Hadza, Hiwi, Ju/’hoansi, Gainj, Tsimane, Yanomamo, Northern Territory Aborigines, and Herero) and five wild chimpanzee groups (Gombe, Kanyawara, Mahale, Ngogo, and Taï). The results state that the most effective modifications towards ZPG would include a combination of more than one of the four demographic scenarios tested, with the most realistic solution including both vital rate alteration and an increase in catastrophes.

Previous research has found that words are replaced faster in language vocabularies the less the word is used, whereas words that are used more frequently endure longer. Drawing from this theory, the authors of this article propose two questions: 1) Is the rate of replacement for Indo-European kinship terms correlated with their usage frequency? 2) How does this relationship differ between kinship terms and core vocabulary? Using phylogenetic comparative methods to analyze 10 kinship categories from 47 Indo-European languages, the authors find that more frequently used kinship terms tend to be replaced at a much slower rate than less frequently used words. Furthermore, this relationship between word replacement rate and usage frequency is stronger for kinship terms than it is for core vocabulary terms.

Previous research has found that words are replaced faster in language vocabularies the less the word is used, whereas words that are used more frequently endure longer. Drawing from this theory, the authors of this article propose two questions: 1) Is the rate of replacement for Indo-European kinship terms correlated with their usage frequency? 2) How does this relationship differ between kinship terms and core vocabulary? Using phylogenetic comparative methods to analyze 10 kinship categories from 47 Indo-European languages, the authors find that more frequently used kinship terms tend to be replaced at a much slower rate than less frequently used words. Furthermore, this relationship between word replacement rate and usage frequency is stronger for kinship terms than it is for core vocabulary terms.