Reconciling the father tongue and mother tongue hypotheses in Indo-European populations

Menghan Zhang; Hong-Xiang Zheng; Shi Yan; Li Jin

doi:10.1093/nsr/nwy083

Reconciling the father tongue and mother tongue hypotheses in Indo-European populations

Natl Sci Rev. 2019 Mar;6(2):293-300. doi: 10.1093/nsr/nwy083. Epub 2018 Aug 20.

Authors

Menghan Zhang^{1

2}, Hong-Xiang Zheng^{2

3}, Shi Yan^{2

3}, Li Jin^{1

2

4}

Affiliations

¹ State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, China.
² Human Phenome Institute, Fudan University, Shanghai 200438, China.
³ Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai 200438, China.
⁴ Chinese Academy of Sciences Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, SIBS, CAS, Shanghai 200031, China.

Abstract

In opposition to the mother tongue hypothesis, the father tongue hypothesis states that humans tend to speak their fathers' language, based on a stronger correlation of languages to paternal lineages (Y-chromosome) than to maternal lineages (mitochondria). To reassess these two competing hypotheses, we conducted a genetic-linguistic study of 34 modern Indo-European (IE) populations. In this study, genetic histories of paternal and maternal migrations in these IE populations were elucidated using phylogenetic networks of Y-chromosomal and mitochondrial DNA haplogroups, respectively. Unlike previous studies, we quantitatively characterized the languages based on lexical and phonemic systems separately. We showed that genetic and linguistic distances are significantly correlated with each other and that both are correlated with geographical distances among these populations. However, when controlling for geographical factors, only the correlation between the distances of paternal and lexical characteristics, and between those of maternal and phonemic characteristics, remained. These unbalanced correlations reconciled the two seemingly conflicting hypotheses.

Keywords: Indo-European populations; Y-chromosomal haplogroup; lexical system; mitochondrial DNA haplogroup; phonemic system.