Language as Adaptation

Some key factors are:

• All human societies have language
• Groups with simpler technologies or social organizations do not have simpler languages
• Most individuals within a society are competent users of language
• Language is innately acquired

These common characteristics suggest that human language is a highly evolved system of communication, formed by natural selection. Unlike other learned capacities, language does not require teaching, yet it involves intricate coordination of vocal cords, lips, tongue, mouth, and various brain regions, simultaneously. In fact, one physiological modification - the descent of the larynx - prevents the ability to drink/eat and breathe at the same time, a characteristic of animals with higher-set larynxes. However, this positioning provides a distinct advantage in producing the wide range of sounds used in human language.

Further, the structure of language provides for nearly infinite combinations that express different ideas in different ways. Phonemes, the most basic unit of perceivable speech, are combined with grammar and syntax to produce novel expressions.

The development of language capacities likely resulted from an evolutionary advantage conferred upon its practitioners in the past, from the most rudimentary forms of symbolic communication, to other intermediate forms. Modern great apes are capable of learning symbolic communication systems, suggesting there are some commonalities in cognition. Whether or not apes utilize a language system in the wild has not yet been demonstrated, although by the same token it has not been disproven.

Language Areas of the Brain

Two specialized language centers in the human brain are Broca's area and Wernicke's area. Broca's area appears to control grammar and syntax in individuals, while Wernicke's area controls the production and comprehension of meaning. In fact, the entire perisylvian region of the brain (usually the left hemisphere) contains structures that have been associated with language comprehension and production.

Examination of endocasts of fossil hominids has suggested to some researchers that the neurological substrate for the production of language was in place as early as 2 million years ago. Enlarged perisylvian structures (like Broca's and Wernicke's areas), along with increasing cerebral asymmetry (another indication of specialized brain function) act as evidence for the early development of language centers. However, difficulties arise in the interpretation of fossil endocast materials, particularly the accuracy of endocrania, endocasts, and the validity of assuming any kind of continuous function from present to past. Other researchers contend that the emergence of language did not occur until after 100,000 years ago, when the production of the full compliment of human-like sounds was not hindered by the morphology of the throat.

However, while the ability to produce the full range of sounds as we know them will reflect a practitioner's ability to reproduce modern languages, it does not exclude the possibility that complex (just not modern) languages developed earlier in human evolution.