query chomsky s single mutation page paper language origin theory duane rumbaugh s book language learn chimpanzee gordon hewe assert chomsky explicitly attribute human language faculty single genetic mutation our ancestor source chomsky exasperatingly neither work nor work chomsky list bibliography nor obvious work cite anyone point place chomsky s writings indeed anyone else s writings suggestion explicitly ve able chomsky s repeat suggestion our language faculty arise byproduct development hence something subject natural selection s quite same thing larry trask cogs university sussex brighton bn qh england larryt cog susx ac uk 