Response to Pepperberg; Herman and Uyeyama; and Shanker, Savage-Rumbaugh, and Taylor

Whether the animals studied by Pepperberg, Herman, and Savage-Rumbaugh can learn prepositions remains an open and important question, though the dolph ins' use of demonstratives and conjuctions suggests an impressive competenc e for at least some closed-class items. It is unlikely that human-like brai n structure can explain the capacities of these animals. Their capacities m ay instead be built upon the cognitive mechanisms favored by social complex ity.