Language Origins and Darwinian Thought

Theories of the origin of language are necessarily speculative. Calvin (1983) suggests that the development of language involved a transfer of the skills involved in stone throwing; Knight (1998) puts the roots of language in ritual; Bickerton (1998) argues that language arose from protolanguage in a single catastrophic mutation. Any one of these accounts might be true, but it is difficult or impossible to gather direct evidence that would allow us to decide between them. An unkind observer might conclude that anything goes, and that one foundation myth is as good as another.

However, such cynicism would be misplaced. In recent years the range of acceptable speculation has been greatly narrowed by the recognition that any account of language origins must be consistent with the principles of evolution by natural selection. For instance, modern Darwinism tells us that complex traits do not evolve without having some function, that all of the intermediate stages in the evolution of modern linguistic capacity must themselves have had adaptive value and that gradual development is more plausible than catastrophic change. These sorts of constraints immediately rule out many stories of language origin, such as the suggestion by Gould (1987) that language is a mere by-product of having a large and complex brain.

The chief problem for a Darwinian account of human speech, however, is the apparent level of altruism involved.