My title today is “language as a biocultural niche and social institution”. As you all know, a major theme running through my lectures so far has been the importance of integrating a life sciences, or biological, perspective on language with a social perspective on language. In this lecture, I directly address this from the point of view of the nature of language itself, its ontology, its nature as an object of study, and as a part of the human ecological niche. Here are some propositions that I want to convince you of. Firstly, the biology of language needs to be understood in both evolutionary and ecological terms. Secondly, language is a biocultural niche and ecological artefact. Thirdly, grammar is not innate. And fourthly, language is a social, semiotic and normative institution, and can be formally so defined and analyzed. Traditionally, in the human sciences there has been an opposition between culture and nature. In this traditional paradigm, culture, like language, is considered to be uniquely human. And therefore language can be either considered to be part of a unique human nature—as in nativist theories—or part of unique human culture, as in environmentalist theories. Or else it is considered that there is an interaction between the two, in the form of an interaction between genes and environment so that it is part of both. Language learning is viewed as being driven by the “exposure” of an organism to an “input” which the learner must internalize. Language is therefore viewed in some kind of sense as being fundamentally external to the language user and learner. There are some problems with this. The first problem, which I alluded to in an earlier lecture, is that the human genome, as we know since the publication of the results of the human genome project, is not sufficiently unique for nativism, at least in my eyes, to be plausible. There is a 95–98% overlap between human and chimpanzee genomes in terms of their genetic material. There is absolutely no difference of orders of magnitude in genetic material available for coding the language capacity. And I will suggest that this simple quantitative similarity makes it unlikely that the human language capacity is genetically encoded, at least in the sense that we are accustomed to thinking about that from Chomskian generative linguistics. However, if we deem language to be part of culture, we also run into certain problems. The main problem is that culture is actually not uniquely human.