AbstractThis paper summarizes the debate on human uniqueness launched by Charles Darwin’s publication of The Origin of Species in 1859. In the progress of this debate, Noam Chomsky’s introduction of the Language-Acquisition Device (LAD) in the mid-1960s marked a turn to the machine model of mind that seeks human uniqueness in uniquely human components of neural circuitry. A subsequent divergence from the machine model can be traced in the short history of ape language research (ALR). In the past fifty years, the focus of ALR has shifted from the search for behavioral evidence of syntax in the minds of individual apes to participant-observation of coregulated interactions between humans and nonhuman apes. Rejecting the computational machine model of mind, the laboratory methodologies of ALR scientists Tetsuro Matsuzawa and Sue Savage-Rumbaugh represent a worldview coherent with Darwin’s continuity hypothesis.