Colloquia Green

– Matches and mismatches between genetic and linguistic diversity

The coevolution of languages and genes represents the ultimate Darwinian paradigm for the reconstruction of population dynamics in time and space, and is still one of the most evoked parallels between cultural and biological diversity. In recent years, scholars have focused on the congruence of linguistic and genetic histories to shed light on population origin, diversification and contact. Popular case studies include the diffusion of major language families, such as Indo-European and Austronesian, but smaller, regional cases of population contact have also been examined.

Mismatches between linguistic and genetic variation are usually disregarded as an exception to the general pattern. But how often do these mismatches actually occur? Can we estimate the incidence of language shift and reconstruct more realistic models of cultural evolution? And which circumstances drive such discontinuities in cultural transmission?

In this talk I will examine the two sides of the gene-language mismatch. The first concerns genetically diverse populations who speak languages of the same family. I will use the case study of the Quechua language family (western South America) to illustrate different patterns of genetic relatedness between speakers of the subfamilies proposed, in particular focusing on the northern and southern varieties. The genetic results support a complex interaction of demographic and cultural forces to account for the spread and diversification of Quechua.

The second side of the mismatch concerns genetically similar populations who speak unrelated languages. This phenomenon, which occurs in various regions of the world, can be directly associated to the formation and maintenance of language barriers within human groups. Such linguistic boundaries, permeable to gene flow, are sustained by socio-cultural forces, for example multilingualism and group identity marking. I propose to address these interaction dynamics with large-scale datasets which take into account the environmental, historical and social contexts.

The final aim of these lines of research is to develop a more realistic understanding of the complex mechanisms behind cultural transmission and cultural change. The fluidity of cultural features through time and space not only impacts our ability of tracing back human prehistory, but also influences the definition of “population” as the unit of research.

9 MAR 2017 | MPI Room 163 | 15.45 – 17.00