Language families, human families

Razib Khan over at ScienceBlogs has an excellent post today on the relationship between population genetics and the spread of languages around the globe. He gives a wide background of the anthropological, linguistic and biological research behind what we know about the evolution of the world’s languages. Razib quotes a 1997 paper by L. L. Cavalli-Sforza, Genes, peoples, and languages:

Most patterns found in the analysis of human living populations are likely to be consequences of demographic expansions, determined by technological developments affecting food availability, transportation, or military power. During such expansions, both genes and languages are spread to potentially vast areas. In principle, this tends to create a correlation between the respective evolutionary trees. The correlation is usually positive and often remarkably high. It can be decreased or hidden by phenomena of language replacement and also of gene replacement, usually partial, due to gene flow.*

The post also reviews a recent paper by Ger Reesink, Ruth Singer, and Michael Dunn: “Explaining the Linguistic Diversity of Sahul Using Population Models”.

The authors studied the languages of Sahul,  the continent that during the last Ice Age covered the area of modern Australia and New Guinea. Using “a Bayesian phylogenetic clustering method, originally developed for investigating genetic recombination”, the authors examine ” the underlying structure of the diversity of these languages, reflecting ancient dispersals, millennia of contact, and probable phylogenetic groups.”

The post is here, and the papers, cited below, can be downloaded by following the links in their titles.

  1. L. Luca Cavalli-Sforza (1997) Genes, peoples, and languages. Proc. Natl . Acad. Sci . USA
    Vol. 94, pp. 7719 –7724.
  2. Reesink G, Singer R, Dunn M. (2009) Explaining the Linguistic Diversity of Sahul Using Population Models. PLoS Biol 7(11): e1000241. doi:10.1371/journal.pbio.1000241
*Errata: The first blockquote in this post was originally attributed to the Reesink paper – that was incorrect. The quote was taken from the Cavalli-Sforza paper. That has been corrected in this edited post.