A comparative wordlist for investigating distant relations among languages in Lowland South America

The history of the language families in Lowland South America remains an understudied area of historical linguistics. Panoan and Tacanan, two language families from this area, have frequently been proposed to descend from the same ancestor. Despite ample evidence in favor of this hypothesis, not all scholars accept it as proven beyond doubt. We compiled a new lexical questionnaire with 501 basic concepts to investigate the genetic relation between Panoan and Tacanan languages. The dataset includes data from twelve Panoan, five Tacanan, and four other languages which have previously been suggested to be related to Pano-Tacanan. Through the transparent annotation of grammatical morphemes and partial cognates, our dataset provides the basis for testing language relationships both qualitatively and quantitatively. The data is not only relevant for the investigation of the ancestry of Panoan and Tacanan languages. Reflecting the state of the art in computer-assisted approaches for historical language comparison, it can serve as a role model for linguistic studies in other areas of the world.

Grammars Across Time Analyzed (GATA): a dataset of 52 languages

Grammars Across Time Analyzed (GATA) is a resource capturing two snapshots of the grammatical structure of a diverse range of languages separated in time, aimed at furthering research on historical linguistics, language evolution, and cultural change. GATA comprises grammatical information on 52 diverse languages across all continents, featuring morphological, syntactic, and phonological information based on published grammars of the same language at two different time points. Here we introduce the coding scheme and design features of GATA, and we describe some salient patterns related to language change and the coverage of grammatical descriptions over time.

Grambank reveals the importance of genealogical constraints on linguistic diversity and highlights the impact of language loss

While global patterns of human genetic diversity are increasingly well characterized, the diversity of human languages remains less systematically described. Here, we outline the Grambank database. With over 400,000 data points and 2400 languages, Grambank is the largest comparative grammatical database available. The comprehensiveness of Grambank allows us to quantify the relative effects of genealogical inheritance and geographic proximity on the structural diversity of the world's languages, evaluate constraints on linguistic diversity, and identify the world's most unusual languages. An analysis of the consequences of language loss reveals that the reduction in diversity will be strikingly uneven across the major linguistic regions of the world. Without sustained efforts to document and revitalize endangered languages, our linguistic window into human history, cognition, and culture will be seriously fragmented.

Untangling the evolution of body-part terminology in Pano: conservative versus innovative traits in body-part lexicalization

Although language-family specific traits which do not find direct counterparts outside a given language family are usually ignored in quantitative phylogenetic studies, scholars have made ample use of them in qualitative investigations, revealing their potential for identifying language relationships. An example of such a family specific trait are body-part expressions in Pano languages, which are often lexicalized forms, composed of bound roots (also called body-part prefixes in the literature) and non-productive derivative morphemes (called here body-part formatives). We use various statistical methods to demonstrate that whereas body-part roots are generally conservative, body-part formatives exhibit diverse chronologies and are often the result of recent and parallel innovations. In line with this, the phylogenetic structure of body-part roots projects the major branches of the family, while formatives are highly non-tree-like. Beyond its contribution to the phylogenetic analysis of Pano languages, this study provides significative insights into the role of grammatical innovations for language classification, the origin of morphological complexity in the Amazon and the phylogenetic signal of specific grammatical traits in language families.

Using lexical language models to detect borrowings in monolingual wordlists

Lexical borrowing, the transfer of words from one language to another, is one of the most frequent processes in language evolution. In order to detect borrowings, linguists make use of various strategies, combining evidence from various sources. Despite the increasing popularity of computational approaches in comparative linguistics, automated approaches to lexical borrowing detection are still in their infancy, disregarding many aspects of the evidence that is routinely considered by human experts. One example for this kind of evidence are phonological and phonotactic clues that are especially useful for the detection of recent borrowings that have not yet been adapted to the structure of their recipient languages. In this study, we test how these clues can be exploited in automated frameworks for borrowing detection. By modeling phonology and phonotactics with the support of Support Vector Machines, Markov models, and recurrent neural networks, we propose a framework for the supervised detection of borrowings in mono-lingual wordlists. Based on a substantially revised dataset in which lexical borrowings have been thoroughly annotated for 41 different languages from different families, featuring a large typological diversity, we use these models to conduct a series of experiments to investigate their performance in mono-lingual borrowing detection. While the general results appear largely unsatisfying at a first glance, further tests show that the performance of our models improves with increasing amounts of attested borrowings and in those cases where most borrowings were introduced by one donor language alone. Our results show that phonological and phonotactic clues derived from monolingual language data alone are often not sufficient to detect borrowings when using them in isolation. Based on our detailed findings, however, we express hope that they could prove to be useful in integrated approaches that take multi-lingual information into account.

Nasal Coarticulation and Prosody in Kakataibo

This paper presents the first phonetic description of the patterns of nasal coarticulation in Kakataibo. While closely related Panoan languages have been described as having anticipatory nasal coarticulation in VN sequences, there are only a few reports of other types of nasal coarticulation. Based on a detailed investigation of the aerodynamic properties of nasality, we account for the full variety of nasal coarticulation patterns in Kakataibo and discuss their interaction with prosody. This paper shows that nasal coarticulation occurs in all contexts in which there is vowel-nasal contiguity, although the amount and patterns of nasal coarticulation are dependent on the directionality of the process, the presence or absence of a syllable boundary and stress.