Implanting human vocal cords into an animal would be a difficult and torturous experiment. But even if someone managed to do it without killing the poor animal, it wouldn’t work, because the muscles and neurons that need to operate those vocal chords would be missing. The brain sends commands to our muscles to move, including to those that orchestrate the fine movements of our vocal chords.

But instead of thinking up Frankenstein like experiments, we can look to animals that happen to have highly developed vocal chords. Can they speak? Turns out there are several species that can imitate human voices, and the winner is an African gray parrot, who was trained by a cognitive scientist. Others that seem to be able to mimic human speech include an orangutan raised in captivity, an elephant in a zoo and a beluga whale in an aquarium. All of these animals have different tricks up their sleeves to modulate their quite advanced vocal tracts, but the main reason they are able to imitate human sounds is due to their vocal learning ability. Similar to humans, these animals have a neural circuit in their forebrain that is able to control the muscles for vocalization. There are also brain regions active when they recognize a match between sounds from others with the sounds of their own.

These animals seem capable of bridging the language barrier that separates us. But can they really "talk" as we do? It's not just a matter of being able to make the sounds. To really count as talking, the animals would have to understand what they mean. An unfortunate natural experiment occurs in some humans, who lose their language ability due to brain damage from a stroke, for example. They still have their vocal chords intact, but they have Aphasia – difficulty in expressing themselves when speaking, trouble understanding speech, and difficulty with reading and writing. So when it comes to speaking, intact, human vocal cords are useless without functioning language centers in the brain.