maintain homeostasis and ensure self preservation. Language hierarchy Given the complexity and range of biological organisms and the further complexity within the neural organization of any particular animal organism, there is a variety of biocommunication languages. A hierarchy of biocommunication languages in animals has been proposed by Subhash Kak: these languages, in order of increasing generality, are associative, re-organizational, and quantum. The three types of formal languages of the Chomsky hierarchy map into the associative language class, although context free languages as proposed by Chomsky do not exist in real life interactions. See also Notes Biological processes Plant cognition Semiotics