Abstract: Syntax is an important characteristic of human communication system that distinguishes humans from other animals. Comparative behavioral studies have shown that other primates besides humans can understand serial order rules; Comparative neurobiological studies have shown that the neural mechanisms that support order processing come from brain regions shared by humans and other primates. Therefore sequence learning ability on which syntax depends have evolutionary continuity between humans and other primates. Lexical constraint hypothesis, event perception hypothesis and self-domestication hypothesis explain the evolutionary origin of human syntax from different perspectives. Future research should clarify whether the neural mechanisms found in artificial grammar tasks are common processors for hierarchical processing in all fields, and further explore the relationship between syntactic processing and semantic processing.

Key words: syntax, sequence learning, artificial grammar, evolutionary continuity, comparative studies