Daniel Everett summarizes the lesson for linguistics from his research of the Pirahã people and their language:

The lesson is that language is not something mysterious that is outside the bounds of natural selection, or just popped into being through some mutated gene. But that language is a human invention to solve a human problem. Other creatures can’t use it for the same reason they can’t use a shovel: it was invented by humans, for humans and its success is judged by humans.