YOUR mother tongue may come from your father. The language of some cultures correlates with a prehistoric influx of foreign males. This is still reflected in the genetics of people today. Written records are powerless to tell us about the evolution of language before writing was invented. Instead, Peter Forster and Colin Renfrew of the University of Cambridge wondered if changes could be traced via maternal or paternal genes, by studying mitochondrial DNA or Y-chromosome genes, respectively.
