Despite more than 200 years of research, the internal structure of the Turkic language family remains subject to debate. Classifications of Turkic so far are based on both classical historical–comparative linguistic and distance-based quantitative approaches. Although these studies yield an internal structure of the Turkic family, they cannot give us an understanding of the statistical robustness of the proposed branches, nor are they capable of reliably inferring absolute divergence dates, without assuming constant rates of change. Here we use computational Bayesian phylogenetic methods to build a phylogeny of the Turkic languages, express the reliability of the proposed branches in terms of probability, and estimate the time-depth of the family within credibility intervals. To this end, we collect a new dataset of 254 basic vocabulary items for thirty-two Turkic language varieties based on the recently introduced Leipzig–Jakarta list. Our application of Bayesian phylogenetic inference on lexical data of the Turkic languages is unprecedented. The resulting phylogenetic tree supports a binary structure for Turkic and replicates most of the conventional sub-branches in the Common Turkic branch. We calculate the robustness of the inferences for subgroups and individual languages whose position in the tree seems to be debatable. We infer the time-depth of the Turkic family at around 2100 years before present, thus providing a reliable quantitative basis for previous estimates based on classical historical linguistics and lexicostatistics.
{"title":"Bayesian phylolinguistics infers the internal structure and the time-depth of the Turkic language family","authors":"A. Savelyev, Martine Robbeets","doi":"10.1093/jole/lzz010","DOIUrl":"https://doi.org/10.1093/jole/lzz010","url":null,"abstract":"\u0000 Despite more than 200 years of research, the internal structure of the Turkic language family remains subject to debate. Classifications of Turkic so far are based on both classical historical–comparative linguistic and distance-based quantitative approaches. Although these studies yield an internal structure of the Turkic family, they cannot give us an understanding of the statistical robustness of the proposed branches, nor are they capable of reliably inferring absolute divergence dates, without assuming constant rates of change. Here we use computational Bayesian phylogenetic methods to build a phylogeny of the Turkic languages, express the reliability of the proposed branches in terms of probability, and estimate the time-depth of the family within credibility intervals. To this end, we collect a new dataset of 254 basic vocabulary items for thirty-two Turkic language varieties based on the recently introduced Leipzig–Jakarta list. Our application of Bayesian phylogenetic inference on lexical data of the Turkic languages is unprecedented. The resulting phylogenetic tree supports a binary structure for Turkic and replicates most of the conventional sub-branches in the Common Turkic branch. We calculate the robustness of the inferences for subgroups and individual languages whose position in the tree seems to be debatable. We infer the time-depth of the Turkic family at around 2100 years before present, thus providing a reliable quantitative basis for previous estimates based on classical historical linguistics and lexicostatistics.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jole/lzz010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46159012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The theory of communication accommodation refers to linguistic processes through which human interactants—consciously or subconsciously—shift their speech and gesture styles to resemble those of their conversation partners. This phenomenon represents a crucial feature of human language and is particularly pronounced in affiliative and/or strong relationships. Communication accommodation is suggested to reflect a need for social integration or identification with other individuals and, as such, plays an important role in communication within closely-knit social units and in particular monogamous relationships. Concerning nonhuman animals, the phenomenon of communication accommodation has received relatively little research attention. Here, we tested whether common ravens (Corvus corax), which are known for their sophisticated communicative skills and lifelong monogamous pair bonds, accommodate their nonvocal signals within a relationship (i.e., pair-partners). Specifically, we investigated whether the nonvocal signals exchanged within pairs become synchronized over time. Our results provided evidence that raven pairs matched their repertoires, with recipients reciprocating the signals of their communication partners in relation to time spent together. This study thus strengthens the hypothesis that the motives to form and maintain affiliate relationships may have been crucial in boosting not only cognitive but also communicative abilities, and provides insight into the role social bonding might have played in the evolution of communicative plasticity.
{"title":"The ‘culture of two’: Communication accommodation in ravens’ (Corvus corax) nonvocal signaling","authors":"E. Luef, A. Maat, Manuela Jäger, S. Pika","doi":"10.1093/jole/lzz008","DOIUrl":"https://doi.org/10.1093/jole/lzz008","url":null,"abstract":"The theory of communication accommodation refers to linguistic processes through which human interactants—consciously or subconsciously—shift their speech and gesture styles to resemble those of their conversation partners. This phenomenon represents a crucial feature of human language and is particularly pronounced in affiliative and/or strong relationships. Communication accommodation is suggested to reflect a need for social integration or identification with other individuals and, as such, plays an important role in communication within closely-knit social units and in particular monogamous relationships. Concerning nonhuman animals, the phenomenon of communication accommodation has received relatively little research attention. Here, we tested whether common ravens (Corvus corax), which are known for their sophisticated communicative skills and lifelong monogamous pair bonds, accommodate their nonvocal signals within a relationship (i.e., pair-partners). Specifically, we investigated whether the nonvocal signals exchanged within pairs become synchronized over time. Our results provided evidence that raven pairs matched their repertoires, with recipients reciprocating the signals of their communication partners in relation to time spent together. This study thus strengthens the hypothesis that the motives to form and maintain affiliate relationships may have been crucial in boosting not only cognitive but also communicative abilities, and provides insight into the role social bonding might have played in the evolution of communicative plasticity.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":"14 1","pages":"1-16"},"PeriodicalIF":2.6,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jole/lzz008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"61538827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The world is facing a crisis of language loss that rivals, or exceeds, the rate of loss of biodiversity. There is an increasing urgency to understand the drivers of language change in order to try and stem the catastrophic rate of language loss globally and to improve language vitality. Here we present a unique case study of language shift in an endangered Indigenous language, with a dataset of unprecedented scale. We employ a novel multidimensional analysis, which allows the strength of a quantitative approach without sacrificing the detail of individual speakers and specific language variables, to identify social, cultural, and demographic factors that influence language shift in this community. We develop the concept of the ‘linguatype’, a sample of an individual’s language variants, analogous to the geneticists’ concept of ‘genotype’ as a sample of an individual’s genetic variants. We use multidimensional clustering to show that while family and household have significant effects on language patterns, peer group is the most significant factor for predicting language variation. Generalized linear models demonstrate that the strongest factor promoting individual use of the Indigenous language is living with members of the older generation who speak the heritage language fluently. Wright–Fisher analysis indicates that production of heritage language is lost at a significantly faster rate than perception, but there is no significant difference in rate of loss of verbs vs nouns, or lexicon vs grammar. Notably, we show that formal education has a negative relationship with Indigenous language retention in this community, with decreased use of the Indigenous language significantly associated with more years of monolingual schooling in English. These results suggest practical strategies for strengthening Indigenous language retention and demonstrate a new analytical approach to identifying risk factors for language loss in Indigenous communities that may be applicable to many languages globally.
{"title":"Language endangerment: a multidimensional analysis of risk factors","authors":"L. Bromham, Xia Hua, C. Algy, F. Meakins","doi":"10.1093/jole/lzaa002","DOIUrl":"https://doi.org/10.1093/jole/lzaa002","url":null,"abstract":"\u0000 The world is facing a crisis of language loss that rivals, or exceeds, the rate of loss of biodiversity. There is an increasing urgency to understand the drivers of language change in order to try and stem the catastrophic rate of language loss globally and to improve language vitality. Here we present a unique case study of language shift in an endangered Indigenous language, with a dataset of unprecedented scale. We employ a novel multidimensional analysis, which allows the strength of a quantitative approach without sacrificing the detail of individual speakers and specific language variables, to identify social, cultural, and demographic factors that influence language shift in this community. We develop the concept of the ‘linguatype’, a sample of an individual’s language variants, analogous to the geneticists’ concept of ‘genotype’ as a sample of an individual’s genetic variants. We use multidimensional clustering to show that while family and household have significant effects on language patterns, peer group is the most significant factor for predicting language variation. Generalized linear models demonstrate that the strongest factor promoting individual use of the Indigenous language is living with members of the older generation who speak the heritage language fluently. Wright–Fisher analysis indicates that production of heritage language is lost at a significantly faster rate than perception, but there is no significant difference in rate of loss of verbs vs nouns, or lexicon vs grammar. Notably, we show that formal education has a negative relationship with Indigenous language retention in this community, with decreased use of the Indigenous language significantly associated with more years of monolingual schooling in English. These results suggest practical strategies for strengthening Indigenous language retention and demonstrate a new analytical approach to identifying risk factors for language loss in Indigenous communities that may be applicable to many languages globally.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jole/lzaa002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49464241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luke Maurits, M. D. Heer, T. Honkola, M. Dunn, O. Vesakoski
The use of computational methods to assign absolute datings to language divergence is receiving renewed interest, as modern approaches based on Bayesian statistics offer alternatives to the discredited techniques of glottochronology. The datings provided by these new analyses depend crucially on the use of calibration, but the methodological issues surrounding calibration have received comparatively little attention. Especially, underappreciated is the extent to which traditional historical linguistic scholarship can contribute to the calibration process via loanword analysis. Aiming at a wide audience, we provide a detailed discussion of calibration theory and practice, evaluate previously used calibrations, recommend best practices for justifying calibrations, and provide a concrete example of these practices via a detailed derivation of calibrations for the Uralic language family. This article aims to inspire a higher quality of scholarship surrounding all statistical approaches to language dating, and especially closer engagement between practitioners of statistical methods and traditional historical linguists, with the former thinking more carefully about the arguments underlying their calibrations and the latter more clearly identifying results of their work which are relevant to calibration, or even suggesting calibrations directly.
{"title":"Best practices in justifying calibrations for dating language families","authors":"Luke Maurits, M. D. Heer, T. Honkola, M. Dunn, O. Vesakoski","doi":"10.1093/jole/lzz009","DOIUrl":"https://doi.org/10.1093/jole/lzz009","url":null,"abstract":"\u0000 The use of computational methods to assign absolute datings to language divergence is receiving renewed interest, as modern approaches based on Bayesian statistics offer alternatives to the discredited techniques of glottochronology. The datings provided by these new analyses depend crucially on the use of calibration, but the methodological issues surrounding calibration have received comparatively little attention. Especially, underappreciated is the extent to which traditional historical linguistic scholarship can contribute to the calibration process via loanword analysis. Aiming at a wide audience, we provide a detailed discussion of calibration theory and practice, evaluate previously used calibrations, recommend best practices for justifying calibrations, and provide a concrete example of these practices via a detailed derivation of calibrations for the Uralic language family. This article aims to inspire a higher quality of scholarship surrounding all statistical approaches to language dating, and especially closer engagement between practitioners of statistical methods and traditional historical linguists, with the former thinking more carefully about the arguments underlying their calibrations and the latter more clearly identifying results of their work which are relevant to calibration, or even suggesting calibrations directly.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2019-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jole/lzz009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45739066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Cuskley, Seán G. Roberts, Stephen Politzer-Ahles, T. Verhoef
A previous study of reviewing at the Evolution of Language conferences found effects that suggested that gender bias against female authors was alleviated under double-blind review at EvoLang 11. We update this analysis in two specific ways. First, we add data from the most recent EvoLang 12 conference, providing a comprehensive picture of the conference over five iterations. Like EvoLang 11, EvoLang 12 used double-blind review, but EvoLang 12 showed no significant difference in review scores between genders. We discuss potential explanations for why there was a strong effect in EvoLang 11, which is largely absent in EvoLang 12. These include testing whether readability differs between genders, though we find no evidence to support this. Although gender differences seem to have declined for EvoLang 12, we suggest that double-blind review provides a more equitable evaluation process.
{"title":"Double-blind reviewing and gender biases at EvoLang conferences: An update","authors":"C. Cuskley, Seán G. Roberts, Stephen Politzer-Ahles, T. Verhoef","doi":"10.1093/jole/lzz007","DOIUrl":"https://doi.org/10.1093/jole/lzz007","url":null,"abstract":"\u0000 A previous study of reviewing at the Evolution of Language conferences found effects that suggested that gender bias against female authors was alleviated under double-blind review at EvoLang 11. We update this analysis in two specific ways. First, we add data from the most recent EvoLang 12 conference, providing a comprehensive picture of the conference over five iterations. Like EvoLang 11, EvoLang 12 used double-blind review, but EvoLang 12 showed no significant difference in review scores between genders. We discuss potential explanations for why there was a strong effect in EvoLang 11, which is largely absent in EvoLang 12. These include testing whether readability differs between genders, though we find no evidence to support this. Although gender differences seem to have declined for EvoLang 12, we suggest that double-blind review provides a more equitable evaluation process.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2019-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jole/lzz007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44543771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pronouns as a diagnostic feature of language relatedness have been widely explored in historical and comparative linguistics. In this article, we focus on South American pronouns, as a potential example of items with their own history passing between the boundaries of language families, what has been dubbed in the literature as ‘historical markers’. Historical markers are not a direct diagnostic of genealogical relatedness among languages, but account for phenomena beyond the grasp of the historical comparative method. Relatedness between pronoun systems can thus serve as suggestions for closer studies of genealogical relationships. How can we use computational methods to help us with this process? We collected pronouns for 121 South American languages, grouped them into classes and aligned the phonemes within each class (assisted by automatic methods). We then used Bayesian phylogenetic tree inference to model the birth and death of individual phonemes within cognate sets, rather than the typical practice of modelling whole cognate sets. The reliability of the splits found in our analysis was low above the level of language family, and validation on alternative data suggested that the analysis cannot be used to infer general genealogical relatedness among languages. However, many results aligned with existing theories, and the analysis as a whole provided a useful starting point for future analyses of historical relationships between the languages of South America. We show that using automated methods with evolutionary principles can support progress in historical linguistics research.
{"title":"Exploring the history of pronouns in South America with computer-assisted methods","authors":"Luis Miguel Rojas-Berscia, Seán G. Roberts","doi":"10.1093/JOLE/LZZ006","DOIUrl":"https://doi.org/10.1093/JOLE/LZZ006","url":null,"abstract":"\u0000 Pronouns as a diagnostic feature of language relatedness have been widely explored in historical and comparative linguistics. In this article, we focus on South American pronouns, as a potential example of items with their own history passing between the boundaries of language families, what has been dubbed in the literature as ‘historical markers’. Historical markers are not a direct diagnostic of genealogical relatedness among languages, but account for phenomena beyond the grasp of the historical comparative method. Relatedness between pronoun systems can thus serve as suggestions for closer studies of genealogical relationships. How can we use computational methods to help us with this process? We collected pronouns for 121 South American languages, grouped them into classes and aligned the phonemes within each class (assisted by automatic methods). We then used Bayesian phylogenetic tree inference to model the birth and death of individual phonemes within cognate sets, rather than the typical practice of modelling whole cognate sets. The reliability of the splits found in our analysis was low above the level of language family, and validation on alternative data suggested that the analysis cannot be used to infer general genealogical relatedness among languages. However, many results aligned with existing theories, and the analysis as a whole provided a useful starting point for future analyses of historical relationships between the languages of South America. We show that using automated methods with evolutionary principles can support progress in historical linguistics research.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2019-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/JOLE/LZZ006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46557532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many languages use pitch to express pragmatic meaning (henceforth ‘tune’). This requires segmental carriers with rich harmonic structure and high periodic energy, making vowels the optimal carriers of the tune. Tunes can be phonetically impoverished when there is a shortage of vowels, endangering the recovery of their function. This biases sound systems towards the optimisation of tune transmission by processes such as the insertion of vowels. Vocative constructions—used to attract and maintain the addressee’s attention—are often characterised by specific tunes. Many languages additionally mark vocatives morphologically. In this article, we argue that one potential pathway for the emergence of vocative morphemes is the morphological re-analysis of tune-driven phonetic variation that helps to carry pitch patterns. Looking at a corpus of 101 languages, we compare vocatives to structural case markers in terms of their phonological make-up. We find that vocatives are often characterised by additional prosodic modulation (vowel lengthening, stress shift, tone change) and contain substantially fewer consonants, supporting our hypothesis that the acoustic properties of tunes interact with segmental features and can shape the emergence of morphological markers. This fits with the view that the efficient transmission of information is a driving force in the evolution of languages, but also highlights the importance of defining ‘information’ broadly to include pragmatic, social, and affectual components alongside propositional meaning.
{"title":"When the tune shapes morphology: The origins of vocatives","authors":"Márton Sóskuthy, Timo B. Roettger","doi":"10.31234/osf.io/ef52k","DOIUrl":"https://doi.org/10.31234/osf.io/ef52k","url":null,"abstract":"Many languages use pitch to express pragmatic meaning (henceforth ‘tune’). This requires segmental carriers with rich harmonic structure and high periodic energy, making vowels the optimal carriers of the tune. Tunes can be phonetically impoverished when there is a shortage of vowels, endangering the recovery of their function. This biases sound systems towards the optimisation of tune transmission by processes such as the insertion of vowels. Vocative constructions—used to attract and maintain the addressee’s attention—are often characterised by specific tunes. Many languages additionally mark vocatives morphologically. In this article, we argue that one potential pathway for the emergence of vocative morphemes is the morphological re-analysis of tune-driven phonetic variation that helps to carry pitch patterns. Looking at a corpus of 101 languages, we compare vocatives to structural case markers in terms of their phonological make-up. We find that vocatives are often characterised by additional prosodic modulation (vowel lengthening, stress shift, tone change) and contain substantially fewer consonants, supporting our hypothesis that the acoustic properties of tunes interact with segmental features and can shape the emergence of morphological markers. This fits with the view that the efficient transmission of information is a driving force in the evolution of languages, but also highlights the importance of defining ‘information’ broadly to include pragmatic, social, and affectual components alongside propositional meaning.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2019-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44439436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stephen Politzer-Ahles, C. Cuskley, Seán G. Roberts, T. Verhoef
{"title":"Errata for Roberts & Verhoef (2016)","authors":"Stephen Politzer-Ahles, C. Cuskley, Seán G. Roberts, T. Verhoef","doi":"10.1093/JOLE/LZZ003","DOIUrl":"https://doi.org/10.1093/JOLE/LZZ003","url":null,"abstract":"","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/JOLE/LZZ003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43876234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Clicks in language evolution: A call for clarification","authors":"A. Voogt","doi":"10.1093/JOLE/LZZ001","DOIUrl":"https://doi.org/10.1093/JOLE/LZZ001","url":null,"abstract":"","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/JOLE/LZZ001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49501465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bayesian phylogenetic methods derived from evolutionary biology can be used to reconstruct the history of human languages using databases of cognate words. These analyses have produced exciting results regarding the origins and dispersal of linguistic and cultural groups through prehistory. Bayesian lexical dating requires the specification of priors on all model parameters. This includes the use of a prior on divergence times, often combined with a prior on tree topology and referred to as a tree prior. Violation of the underlying assumptions of the tree prior can lead to an erroneous estimate of the timescale of language evolution. To investigate these impacts, we tested the sensitivity of Bayesian dating to the tree prior in analyses of four lexical data sets. Our results show that estimates of the origin times of language families are robust to the choice of tree prior for lexical data, though less so than when Bayesian phylogenetic methods are used to analyse genetic data sets. We also used the relative fit of speciation and coalescent tree priors to determine the ability of speciation models to describe language diversification at four different taxonomic levels. We found that speciation priors were preferred over a constant-size coalescent prior regardless of taxonomic scale. However, data sets with narrower taxonomic and geographic sampling exhibited a poorer fit to ideal birth–death model expectations. Our results encourage further investigation into the nature of language diversification at different sampling scales.
{"title":"Influence of the tree prior and sampling scale on Bayesian phylogenetic estimates of the origin times of language families","authors":"Andrew M. Ritchie, S. Ho","doi":"10.1093/JOLE/LZZ005","DOIUrl":"https://doi.org/10.1093/JOLE/LZZ005","url":null,"abstract":"Bayesian phylogenetic methods derived from evolutionary biology can be used to reconstruct the history of human languages using databases of cognate words. These analyses have produced exciting results regarding the origins and dispersal of linguistic and cultural groups through prehistory. Bayesian lexical dating requires the specification of priors on all model parameters. This includes the use of a prior on divergence times, often combined with a prior on tree topology and referred to as a tree prior. Violation of the underlying assumptions of the tree prior can lead to an erroneous estimate of the timescale of language evolution. To investigate these impacts, we tested the sensitivity of Bayesian dating to the tree prior in analyses of four lexical data sets. Our results show that estimates of the origin times of language families are robust to the choice of tree prior for lexical data, though less so than when Bayesian phylogenetic methods are used to analyse genetic data sets. We also used the relative fit of speciation and coalescent tree priors to determine the ability of speciation models to describe language diversification at four different taxonomic levels. We found that speciation priors were preferred over a constant-size coalescent prior regardless of taxonomic scale. However, data sets with narrower taxonomic and geographic sampling exhibited a poorer fit to ideal birth–death model expectations. Our results encourage further investigation into the nature of language diversification at different sampling scales.","PeriodicalId":37118,"journal":{"name":"Journal of Language Evolution","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/JOLE/LZZ005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48693538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}