The automatic set of human development, i.e. at birth a baby’s brain develops, the larynx much higher in the throat, then as the baby grows, the larynx descends, the brain develops, the child assumes upright position and starts walking and talking.
Due to these observations on language acquisition of humans, it is supposed that may be language ability is innate, that humans are born with the special ability for language.
This innateness hypothesis points to something in human genetics. It may be that there somewhere in time there was a crucial gene mutation that became the source of this innate ability.