Abstract:
It is commonly held that language evolved de novo in our own species, within the past 100,000 years. This is at odds with Darwinian theory which implies that language, like other complex systems, must have evolved incrementally. One approach to such a theory is to suppose that language evolved from manual gestures. Several lines support this. These include the nature of the primate mirror system and its homology with the language circuits in the human brain, the superiority of manual over vocal intentionality in great apes, the ready invention of sophisticated signed languages by the deaf, the correlation between handedness and cerebral asymmetry for language, and the critical role of pointing in the way young children learn language. A gradual switch from manual to facial and vocal expression may have occurred late in hominin evolution, with speech reaching its present level of autonomy only in our own species, Homo sapiens.
