More recent hypotheses that I’ve read is that what we think of language evolved as a tool for internal thought and ordering of ideas and perceptions. Executive

More recent hypotheses that I’ve read is that what we think of language evolved as a tool for internal thought and ordering of ideas and perceptions. Executive function, in a sense. The externalization of language, whether vocal or gestural, evolved later as a means of serializing the internal language in order to transmit those thoughts to others. Under this hypothesis, the serial nature of language is a limitation of the externalization methods (you can’t produce several words at once, or hear several at once), whereas internal language itself need not be a linear process.