Should Mother Tongue be Father Tongue?

A new paper, published in Science last week, has reviewed some of the correlations which suggest that language change may be subject to sex-specific transmission. This has been discovered through looking at Y-chromosome DNA types. Modern male DNA (Y-Chromosome) is found to be the DNA from the population who originally spoke the language which has survived, whereas modern female DNA is often not the DNA of the population which spoke the language which has survived.

This evidence has come from, among others, a study by Chaubey (2011) with evidence for the Indian subcontinent. Austroasiatic languages are spoken by tribes with a high proportion of immigrant Y-chromosome DNA from East Asia, but with a high percentage of local female (mitochondrial) DNA. This pattern was also true of the Tibeto-Burman language family in northeastern India.

Other studies found matching correlations in Africa and found that Niger-Congo languages correlate with Y-Chromosome types, but the female DNA, which correlated more with geography (Wood et al. (2005) and de Filippo et al. (2011)).

Sex-biased language change can also be seen in the expansion of the Malayo-Polynesians in New Guinea. New Guinea has populations of Malayo-Polynesian speakers and also populations of Melanesian speakers. Malayo-Polynesian female DNA is about the same in both Malayo-Polynesian speaking areas and Melanesian speaking areas. However, the Malayo-Polynesian Y-Chromosome is found way more in the Malayo-Polynesian speaking areas than the Melanesian speaking areas.

This pattern is also seen in Iceland where the female DNA is mainly British, but the Y-chromosome is mainly Scandinavian. This follows the pattern because the Icelandic language is also Scandinavian.

Forster and Renfrew (authors of the Science paper) show that these findings complement studies such as Stoneking and Delfin who found that in East Asia, it is women who move after marriage rather than men. This means that if a man and woman migrate to a populated area their female offspring will move to other villages when married but their male offspring will remain static meaning that their language will stay in the same place as their Y-Chromosomes.

Is this the only mechanism at work when correlations of sex-specific language change can be seen? Others have hypothesized things such as farming and trade might be a factor. Groups of emigrating agriculturalists may also contribute where men outnumber women and take wives from the local community they were moving to. Men are also biologically capable of passing on and spreading about much more of their DNA than women can. It may also be the case that it is the father's language rather than the mother's which will be dominant within a family but I think more research would have to be done on this.

Interestingly the opposite correlation to the ones seen above is seen in Greenland where both the language and female DNA is Eskimo but the Y-Chromosome DNA is European.

  • Kevin

    Is it just me or would saying 'gender-specific' be much more appropriate than 'sex-specific'? The latter suggests a biological effect, even though the bias is clearly purely cultural. Only the genetic methods to trace the effect are based on actual sex, which can be done because there's a strong correlation between the two, but it doesn't imply a direct mechanistic link at all.

  • I had that exact thought while I was writing this but Forster and Renfrew use "sex-specific" which is why I stuck with that term as I didn't want to misrepresent what they were saying. But yes, I agree that gender would be a more appropriate term to use when talking about cultural phenomena. However, I would say that sex and gender are SO strongly correlated that it is safe to draw direct mechanistic links.

  • Kevin

    A link, yes, but not a direct link to how men and women learn or change language differently simply because of their biological dispositions. The link is biologically determined sex ā†’ cultural behaviour ā†’ language differences, not biologically determined brain/language-functions ā†’ language differences. Using 'sex-specific' (and thus conflating the two levels) lends itself to speculations around the second interpretation, even though this is effectively ruled out if you look at the diversity of the data.

  • syg

    Interesting data, wondering if there are some "microscope" researches on this topic, such as ethnography or something.

  • Hi Kevin, yes, I see your point more clearly now. Though "cultural behaviour" is a very broad term and includes use of language and it's been argued before that cognitive biases do directly affect language change. However, I do see that this is probably not what is at the root of the correlations seen here. Most of these findings are reported as correlations and refrain from discussing causations which is probably why they can get away with talking about sex-specific effects but I see your point that you'd have to be careful when one does start trying to disentangle the causations.

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  • Caravelle

    Question : biological or cultural (if it's confirmed of course) ? It could be that children are more likely to adopt the dominant language of their environment, and fathers tend to be more dominant either by virtue of living in a male-dominant society, or because the father belongs to the dominant culture (because women are more exogamous in that region).

    That's interesting, because as I guess the term "mother tongue" implies, people usually assume that language is transmitted through the mothers who interact more with the children at a young age. But children forget their mother tongue if their mother is the only one who ever uses it, don't they ?

    I do find it very interesting how children (and adults, although I'd think it's a different mechanism) adopt and forget various languages. I personally try to hang on to as many languages as I can but so many people don't, and it's interesting which languages they keep or adopt and which they manage to forget altogether.

  • I don't think anyone's arguing that languages are transmitted genetically. Languages being transmitted by fathers is definitely cultural and fathers being more dominant is certainly something which needs to be considered.