Steven Pinker, following Noam Chomsky and ultimately Immanuel Kant, believes that humans are born with a "language instinct:" a neural processing network that contains a universal grammar that has developed specifically for encoding and decoding human languages.
Derek Bickerton has suggested that the language faculty may have evolved in two major steps. The first is a protolanguage of symbolic representation and verbal and/or gestural signs, and the second formal syntax. Symbolic representation would allow modeling of reality and constructional learning, and, together with some communicative ability, would permit shared learning. Syntax would permit significantly improved precision and clarity in thought and communication.
The evolution of such an inherited trait in the genus Homo may be one thing that explains why anatomically modern humans expanded at the expense of other hominid species in the history of human evolution. Many mainstream theories of human evolution affirm that all current human beings are the descendants of a relatively small population of anatomically modern humans that appeared in Africa less than one million years ago. The development of an inherited gift for language, or its superior attainment over other species of Homo such as Neandertal man, is one possible explanation for the ascendency of anatomically modern humans over other primitive human groups at the time. At least one gene, FOXP2, is claimed to be involved with the development of language.