If you frequently answer questions with “huh?” chances are you’ve been disapprovingly told to say “pardon” instead. But what is the purpose of this little word, so often dismissed as rude or lazy? Until relatively recently, the field of linguistics has paid little attention to such words. But researchers at the Institute for Psycholinguistics in Nijmegen, the Netherlands, have shed some light on their importance. According to their research, “huh?” is in fact a universal word—perhaps the only one.

Mark Dingemanse and his colleagues worked with recordings of people speaking ten different languages. They found that all the languages had a word with a similar meaning to “huh?” (something indicating that clarification is required); interestingly, all the equivalent words also had a very similar form to “huh?”. In each language, the vowel seems to have evolved for ease and speed—none of the words found contained vowels which required moving the tongue (such as “ee” or “oo”). If a sound preceded the vowel, it was either an h or a glottal stop.

Where there is no shared ancestry at all or borrowing from other languages, the baseline linguistic assumption is that there is no reason for a word to be similar across languages. “Huh?” seems to be an exception to this principle. Following their original study, Dingemanse’s team analysed a further 21 languages and confirmed the similarities. Of course, people cry and laugh from birth regardless of what language they speak; some vocalisations do not have to be learnt and do not need a linguistic structure. But precisely because of this, these sounds are not considered to be words. “Huh?”, on the other hand, is not used by children until they start speaking. The form that the “huh?” equivalent takes depends on the structure of that particular language—hence in Russian, which has no “h” sound, this quizzical vocalisation is more like “ah?”

To explain why “huh?” is so similar across languages, Dingemase proposes an evolution-based theory, arguing that the current form of the word is the result of “selective pressures in its conversational environment.” In other words, unlike conventional words that designate a particular thing, “huh?” has evolved to be suited to its purpose; for example it is short, requires little effort in terms of the sounds used, and can easily be given an interrogative tone. Conversely, the word “table” is no more suited to describing a table than the word “ogleborg”. By a phenomenon known as convergent evolution, words very similar to “huh?” sprang into being in different languages because the conversational requirements were similar in each language. Dingemanse compares it to sharks and dolphins, who “arrived at the same body plan not because they share certain genes, but because they share an environment.”

Applicants for Linguistics should think about how the theory of evolution can be usefully drawn upon in the field of linguistics, and to what extent such comparisons hold true. They may wish to think about what aspects of human language are as yet neglected by research, and what aspects interest them in particular.

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