Phylogenetic linguistic evidence and the Dene-Yeniseian homeland

Sicoli & Holton (2014) (PLoS ONE 9:3, e91722) use computational phylogenetics to argue that linguistic data from the putative, but likely, Dene-Yeniseian macro-family are better compatible with a homeland in Beringia (i.e., northeastern Siberia plus northwestern Alaska) than with one in central Siberia or deeper Asia. I show that a more careful examination of the data invalidates this conclusion: in fact, linguistic data do not support Beringia as the homeland. In the course of showing this, I discuss, without requiring a deep mathematical background, a number of methodological issues concerning computational phylogenetic analyses of linguistic data and drawing inferences from them. The aim is to contribute to making computational phylogenetics less of a black box for historical linguists. I conclude with a brief overview of the current evidence bearing on the Dene-Yeniseian homeland from linguistics, archaeology, folklore studies and genetics, and suggest current best practice for linguistic phylogenetics, the use of which would have helped to avoid some of the problems in Sicoli and Holton’s Dene-Yeniseian study, and in turn the percolation of those problems into subsequent synthetic interdisciplinary research.

Phylogeny in Phonology: How Tai Sound Systems Encode Their Past

The study of sound change is foundational to traditional historical linguistics, particularly the linguistic comparative method. It is well established that the phonology of modern languages encodes useful data for studying the history of those languages, and their genetic relationships to one another. However, phonology has typically been the means to the end, enabling the comparative method, and coding of a comparative lexicon for cognacy. Once coded, the particular sounds involved no longer factor into the analysis. This study examines whether the phoneme inventories and phonotactic profiles of a set of languages themselves contain phylogenetic signal detectable using established statistical tests D statistic (Fritz & Purvis 2010), K (Blomberg et al 2003), and NeighborNet delta score (Holland et al 2002) and Q-residual (Gray et al 2010). This study adds to the growing body of work on the use of phonological traits in computational phylogenetics for linguistics. Using data from 20 Tai lects from the Kra-Dai language family, this study confirms and extends previous findings. This includes detection of strong phylogenetic signal in phoneme frequency and biphone transition probabilities, but also relatively strong phylogenetic signal detected in even coarse-grained phoneme and biphone presence/absence, which previous work was unable to do.

Support for linguistic macrofamilies from weighted sequence alignment

Computational phylogenetics is in the process of revolutionizing historical linguistics. Recent applications have shed new light on controversial issues, such as the location and time depth of language families and the dynamics of their spread. So far, these approaches have been limited to single-language families because they rely on a large body of expert cognacy judgments or grammatical classifications, which is currently unavailable for most language families. The present study pursues a different approach. Starting from raw phonetic transcription of core vocabulary items from very diverse languages, it applies weighted string alignment to track both phonetic and lexical change. Applied to a collection of ∼1,000 Eurasian languages and dialects, this method, combined with phylogenetic inference, leads to a classification in excellent agreement with established findings of historical linguistics. Furthermore, it provides strong statistical support for several putative macrofamilies contested in current historical linguistics. In particular, there is a solid signal for the Nostratic/Eurasiatic macrofamily.