Evolution of Human Speech and Language in Hominids

Speech Articulation and the Vocal Tract

Articulation means movement. In speech, articulation is the process by which speech sounds are formed. The articulators are the movable speech organs, including the tongue, lips, jaw, velum, and pharynx. These organs, together with related tissues, comprise the vocal tract — the resonating cavities of speech production that extend from the larynx (voice box) to the lips or nostrils.

Probably the most important factor distinguishing humans from apes and other animals is the remarkable capacity for language. The ability to communicate with others of one's own kind in abstract, symbolic speech is unique to humans, and evolutionists have never been able to bridge the tremendous gulf between this ability and the grunts, barks, and chattering of animals.

Some researchers have made extravagant claims about the potential for teaching chimpanzees to speak, or have developed highly imaginative speculations as to how animal noises may have evolved into human languages. Such notions, however, are not based on real scientific observation or evidence. Human speech production is accomplished by the coordination of muscular actions in the respiratory, laryngeal, and vocal tract systems. Typically, the word "articulation" refers to the functions of the vocal tract, but speech production requires the action of all three systems. A full account of speech production would go beyond articulation to include such topics as intonation and emotional expression.

Hominid Evolution and the Fossil Record

The story begins about 3.5 million years ago with the appearance of a group of animals collectively known as australopithecines. Australo means "southern" and pithecines means "apes." These "southern apes," initially discovered in South Africa, were small, apparently upright-walking apes. Around 2 million years ago, a new creature appeared that is now placed in the genus Homo: Homo habilis.

Homo habilis possesses the same stature as the australopithecines but with a slightly larger brain. It is also suggested that he used a few primitive tools. Next appears the real star of human evolution, Homo erectus. Homo erectus possesses the skeletal frame of modern humans, though somewhat more robust, and his brain capacity is closer still to that of humans. Homo erectus also used more advanced tools.

This "almost" human persisted, we are told, for over 1.5 million years, after which nearly modern humans (Homo sapiens) began to appear. Soon the offshoot Neanderthals arose, and at about the same time thoroughly modern humans appeared within the last 100,000 years. Evolutionists as well as creationists have in recent years come to believe in the monophyletic origin of all the tribes and races of humankind.

Most earlier evolutionists, however, believed in humanity's polyphyletic origin, thinking that each of the major "races" had evolved independently from a different hominid line. This idea easily leads to racism — the belief that one race is innately superior to another. If each race has a long, independent evolutionary history, slowly developing its distinctive character through random mutation and natural selection, then it is nearly certain that there has been a differential rate of evolution between the different races, with some evolving to higher levels than others.

The word "hominid" refers to members of the family of humans, Hominidae, which consists of all species on our side of the last common ancestor of humans and living apes. Hominids are included in the superfamily of all apes, the Hominoidea, whose members are called hominoids. Although the hominid fossil record is far from complete and the evidence is often fragmentary, there is enough to give a good outline of the evolutionary history of humans.

The time of the split between humans and living apes used to be thought to have occurred 15 to 20 million years ago, or even up to 30 or 40 million years ago. Some apes occurring within that time period, such as Ramapithecus, were once considered hominids and possible ancestors of humans. Later fossil finds indicated that Ramapithecus was more closely related to the orangutan, and new biochemical evidence indicated that the last common ancestor of hominids and apes occurred between 5 and 10 million years ago, probably toward the lower end of that range (Lewin 1987). Ramapithecus is therefore no longer considered a hominid. The field of science that studies the human fossil record is known as paleoanthropology — the intersection of paleontology (the study of ancient life forms) and anthropology (the study of humans).

Although evolutionists are now in practically complete agreement that all present groups of humans came originally from one single population of ancestral humans, they are currently in considerable disarray as to exactly what that lineage may have been. The australopithecines and the Homo erectus group of supposed hominids are no longer considered humanity's progenitors, since fossils of true humans have been found that are dated earlier than any of these.

Not only do these discoveries indicate that humanity's unique bodily structure has — so far as actual fossil evidence goes — always been distinct from that of apes, but also that humans have always possessed their unique capacity for communication. As Donald Johanson has suggested, there is even the possibility that early hominids had "some kind of social cooperation and some sort of communication system." Back to the very beginning of human existence, therefore, insofar as it can be elucidated by archaeological excavation and anthropological analysis, humans have always been human — culturally and linguistically as well as physically and mentally.