The evolution of syntax: Signs, concatenation and embedding

The paper argues that the structure, derivation and evolution of syntax is given by the sequence (elements, concatenation, embedding). We discuss the implications of this sequence for language and the numeral system in general and on the evolution of language in particular. A four-stage model of the evolution of syntax, broadly compatible with several earlier scenarios, is proposed. The four stages are (1) signs, (2) increased number of signs, (3) commutative concatenation, and (4) noncommutative concatenation. We support the model by showing that its stages can be adaptive per se, which could explain why they evolved. We also identify two preconditions for maintaining the stages: stage (2) depends on the ability to conceptualize asymmetric relations between concepts and the adaptiveness of stage (3) depends on cultural constraints on linguistic interpretation.