In Turkish, 'Ali geldi' means 'Ali came, and I witnessed it'. If you only heard about it or worked it out, you say 'Ali gelmiş'. This grammatical marking of where information comes from, called evidentiality, exists in many languages. Tariana, spoken in the Amazon, distinguishes what you saw, sensed some other way, inferred from clues, assumed, or were told. You can't state a fact without saying how you got it.
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.