In 1866 the French Academy of Sciences banned discussion of the origin of language. The nature of language in an evolutionary context is a big question which just keeps giving. But obviously the French academy thought that it was giving a little too much without resolution. Despite being fascinated with the topic at one point, and reading books such as The Symbolic Species and The Language Instinct, I've come away with the opinion that there's a lot to the evolution of language which is just unknown. A few years ago some researchers were strongly implying that fully fleshed out language is what led to the behavioral revolution of anatomically modern humans ~50,000 years ago (see The Dawn of Human Culture). But now many scholars are arguing that language may be an ancestral character of the descendants of H. erectus. Of course to gain some clarity on the evolutionary origins of language we need to think deeply about what language is for. The simplest explanation is that language is to communicate. You tell your mother that you are hungry. You communicate with your peers about whatever cooperative task you are engaged in. But a new article in The New York Times highlighting the discovery in the first generation of a new language emphasizes one aspect that I think we often forget:
Carmel O’Shannessy, a linguist at the University of Michigan, has been studying the young people’s speech for more than a decade and has concluded that they speak neither a dialect nor the mixture of languages called a creole, but a new language with unique grammatical rules. The language, called Warlpiri rampaku, or Light Warlpiri, is spoken only by people under 35 in Lajamanu, an isolated village of about 700 people in Australia’s Northern Territory. In all, about 350 people speak the language as their native tongue. Dr. O’Shannessy has published several studies of Light Warlpiri, the most recent in the June issue of Language. “Many of the first speakers of this language are still alive,” said Mary Laughren, a research fellow in linguistics at the University of Queensland in Australia, who was not involved in the studies. One reason Dr. O’Shannessy’s research is so significant, she said, “is that she has been able to record and document a ‘new’ language in the very early period of its existence.” ... Dr. O’Shannessy suggests that subtle forces may be at work. “I think that identity plays a role,” she said. “After children created the new system, it has since become a marker of their identity as being young Warlpiri from the Lajamanu Community.”
Language is to a great extent a hard-to-fake identity marker. Though you may learn a language as an adult with a modicum of fluency, accent and idiom often make plain to genuine 'native speakers' that you did not learn the language in childhood. Humans are an extremely social organism for mammals, with elaborated complexity in institutional structures, both explicit and implicit. The data density of linguistic communication facilitates this, but, the identity marker of language may be critical in maintaining group cohesion due to the character of the trait's relative immunity to 'cheaters' being able to infiltrate. The emergence of new languages in such a punctuated fashion does I suspect give us a sense of the fluctuating nature of cultural fission in the prehistoric past. There is much yet to learn about the origins of language by surveying more deeply the variation which is present, and fast vanishing.