On 10 July 1547, before King Henry II, Guy Chabot de Jarnac fought a duel against La Châtaigneraie, a swordsman thought unbeatable. Jarnac surprised him with a cut to the back of the knee, allowed but unexpected, and won. In French, a 'coup de Jarnac' first meant a clever, unforeseen stroke. Its now usual sense of a treacherous stab in the back came later, and betrays history.
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.