Our capacity for language is one of the attributes often cited as what makes humans so distinct from other animals. It’s a controversial distinction, because we’ve observed other species communicate in very interesting and effective ways: whales sing, dolphins whistle, birds do whatever it is they do to switch places while in formation. Parrots, of course, can be trained to mimic human speech! But there’s a difference between replicating instinctual sounds with fixed meanings and…