In the 2011 census, people in India gave 19,569 different names for their mother tongue. After grouping variants, dialects and spellings, statisticians settled on 121 languages, 22 of which are listed in the Constitution. Rupee banknotes even print their value in 15 of these languages, on top of Hindi and English. A headache for administrators, and a treasure trove for linguists.
In Kuşköy, a mountain village in northern Turkey, people talk across valleys by whistling Turkish. A 2015 study showed that whistled Turkish draws on both hemispheres fairly evenly, whereas spoken Turkish relies mostly on the left. The physical form of the signal, it turns out, matters to the brain.
Speech has no gaps between words. In 1996, researchers played 8-month-old babies a continuous stream of made-up syllables for just two minutes. The infants picked out the 'words' by tracking which syllables tend to follow one another. That's probability calculation, done without a calculator or any visible effort.