ELI5: Origin of Human Language

William Burroughs thought of language as a virus. I am not sure if he was serious or if this was simply one of the bases of his science fiction.

The first teenage girl. Can't shut them up.

• We don't exactly know why we have language

• We know that other animals use communication in ways that approximate our language, but are not as complex, innovative, or adaptive (e.g. some animals show signs of syntax). Some animals uses means of communication that are not well understood by us (e.g. sonar, scent, frequencies above and below our own hearing threshold) and thus finding meaning within those events is very difficult. This is a really interesting area of research, one where the line that separates human from animal becomes more grey as the years pass.

• We know that human languages don't need to be complex in order to "work", within the diversity of human languages there is a great diversity of rules that allow them to function.

• It is very likely that proto-languages began developing early on in Homo evolution, possibly with Homo erectus about 1-2 million years ago. They would have communicated exactly like a modern human, but it is likely that the selective pressures that began to guide the Homo genus towards more complex methods of communication began during this early period of our cognitive development. "The discovery of Turkana boy (H. [erectus]) in 1984 gave evidence that, despite its Homo-sapiens-like anatomy, it may not have been capable of producing sounds comparable to modern human speech. Erectus likely communicated in a proto-language lacking the fully developed structure of modern human language but more developed than the non-verbal communication used by chimpanzees. Such inference has been challenged by the discovery of H. erectus vertebrae some 150,000 years older than the Turkana Boy in Dmanisi, Georgia, that reflect vocal capabilities within the range of H. sapiens (modern humans). Both brain-size and the presence of the Broca's area also support the use of articulate language." Basically this tells us that the fossils are a bit ambiguous. We have some physical evidence that the right physical structures (brain and vocal chords) were there or beginning to develop but we are not sure if they had the cognitive ability to create a language in the way we think of it now. They certainly communicated with one another in ways that are more complex than what we currently think the limits of animal communication are, but how less complex they are from modern humans is a question that remains unanswered.

• Some scholars theorize that gestural language may have come before spoken language (e.g. the hunting techniques by the Kung!, a hunter-gatherer society, involve swat-team like signals - they can be complex enough to indicate intent etc. but do not require sound). Some scholars conjecture that Neanderthals, early humans, and extinct Homo species like H. erectus may have used gestural languages as a primary form of communication rather than sounds as their vocal anatomy may not have been complex enough to allow for modern vocalization. In other words, the "gesture language hypothesis" excludes the need for a species to have vocal chords that approximate a modern human's vocal apparatus in order to have modern language, but rather all they would need would be the correct complexity of brain structures to create a gesture based language.

• We are not aware of any specific gene, or series of genes, that account for all aspects of modern languages. (e.g. even if we had the technology, we could not alter the genome of a chimpanzee so that they could understand human language). We do know that the FOXP2 gene effects our ability to speak but we are not sure exactly what role it had in the development of modern languages. Other animals have the FOXP2 gene so it is obviously not enough on its own.

• "Behavioral modernity is a term used in anthropology, archeology and sociology to refer to a set of traits that distinguish present day humans and their recent ancestors from both other living primates and other extinct hominid lineages. It is the point at which Homo sapiens began to demonstrate an ability to use complex symbolic thought and express cultural creativity. These developments are often thought to be associated with the origin of language. Elements of behavioral modernity include finely-made tools, fishing, long-distance sharing or exchange among groups, self-ornamentation, figurative art, games, music, cooking and burial. There are two main theories regarding when modern human behavior emerged. One theory holds that behavioral modernity occurred as a sudden event some 50 kya in prehistory, possibly as a result of a major genetic mutation or as a result of a biological reorganization of the brain that led to the emergence of modern human natural languages...The second theory holds that there was never any single technological or cognitive revolution. Proponents of this view argue that modern human behavior is the result of the gradual accumulation of knowledge, skills and culture occurring over hundreds of thousands of years of human evolution."