Miyagawa is not suggesting that birdsong literally gave rise to human language; the two systems of communication did not evolve from a common ancestor. But sometime in the past fifty thousand to eighty thousand years, he says, the two approaches to communication merged in the form of language as we recognize it today. “Yes, human language is unique,” says Miyagawa, “but its two components have antecedents in the animal world. According to our hypothesis, they came together uniquely in human language.”
