Let us define linguistic replicators, informally, as recurrent fragments of language structure (such as words, morphemes, speech sounds, and constructions) which can be transmitted from one generation of speakers to the next. A replicator has an evolutionary relevance only if it can be “internalised” by new speakers as a permanent information structure residing in their brains. Although the crucial part of the process takes place during first-language aquisition, our mother tongue continues to be developed and modified in our later years. We can also learn one or more foreign languages. Our brain is actually the place where language contact takes place and where replicators can penetrate language barriers.
It should be clear by now that replicators live lives of their own. It’s much easier for them to spread inside a speech community (especially if it’s predominantly monolingual) than infect a different language; that’s why their genealogies lie mostly inside the branches of the family-tree of languages. But their lateral transmission (from language to language) is not only possible but common. Linguistic replicators and the languages that contain them co-evolve to a significant degree but are not doomed to each other’s company forever.
|How many species? Reticulate evolution|
©2011 Australian Institute of Marine Science, Coral Reef Research