The Origins of Culture-2

Bipedalism
One of the earliest of the major hominid characteristics to have evolved, distinguishing the species Homo from its nearest primate relatives—the gorilla, chimpanzee, and orangutan—was bipedalism, an adaptation to a completely erect posture and a two-footed striding walk. Almost all other mammals stand, walk, and/or run on four limbs.
Those that stand on two have quite different postures and gaits from humans—kangaroos hop on their two feet; some monkeys only on occasion walk bipedally, especially when carrying food; chimpanzees are capable of brief bipedal walks, but their usual means of locomotion is knuckle-walking, standing on their hind legs but stooping forward, resting their hands on the knuckles rather than on the palms or fingers. So, even though forms of bipedalism are observable in other primates, they are unlike the human type: all other forms of bipedal walking involve straight or bowed spines, bent knees, grasping (prehensile) feet, and some use of the hands to bear part of the body weight during locomotion. The uniquely S-shaped spinal column of humans places the center of gravity of the body directly over the area of support provided by the feet, thus giving stability and balance in the upright position.

Tools
Fossils discovered in Africa provide evidence that hominids walked erect and had a bipedal stride even before the great increase in their brain size. Complete bipedalism freed the human hand, allowing it to become a supremely sensitive limb for precise manipulation and grasping. The most important structural detail in this refinement was the elongated human thumb, which could rotate freely for the first time and, thus, be fully opposable to the other fingers. No doubt, this development made tool making and tool use possible. Moreover, some linguists claim that the erect posture gave rise to the subsequent evolution nf the physiological apparatus for speech, since it brought about the lowering and positioning of the larynx for controlled breathing. In a phrase, bipedalism, tool-making, and language were probably intertwined in their origins (Wilson 1998).
Although other species, including some non-primate ones, are capable of tool use, only in the human species did complete bipedalism free the hand sufficiently to allow it to become a supremely sensitive and precise manipulator and grasper, thus permitting proficient tool making and tool use in the species. The earliest stone tools date back to about 2.5 million years ago. By 1.5 million years ago, sites in various parts of eastern Africa contain not only many stone tools, but also animal bones with scratch marks that research has shown could only have been left by human-like cutting actions. One thing is certain—only in the human species does one find the capacity to fashion a great diversity of tools from the raw materials found in the environment to meet virtually any need that may arise (Montagu 1983, Noble and Davidson 1996: 22-56).

Brain Growth

Shortly after becoming bipedal, the evidence suggests, the human species underwent rapid brain expansion. In the course of human evolution the size of the brain has more than tripled. Modern humans have a braincase volume of between 1300 and 1500 cc. The human brain has also developed three major structural components that undergird the unique mental capacities of the species—the large dome-shaped cerebrum, the smaller somewhat spherical cerebellum, and the brainstem. The size of the brain does not determine the degree of intelligence of the individual; this appears to be determined instead by the number and type of functioning neurons (nerve cells) and how they are structurally connected with one another. And since neuronal connections are conditioned by environmental input, the most likely hypothesis is that any form of intelligence, however it is defined, is most likely a consequence of upbringing. Unlike the early hominid adult skulls, with their sloping foreheads and prominent jaws, the modern human skull —with biologically insignificant variations—retains a proportionately large size, in relation to the rest of the body.
The large brain of modern-day Homo culturalis is more than double that of early tool-makers. This great increase in brain size was achieved by the process of neoteny, i.e. by the prolongation of the juvenile stage of brain and skull development in neonates (newborns). As a result, human infants must go through an extended period of dependency on, and stimulation by, adults. In the absence of this close external bond in the early years of life, the development of the infant's brain would remain incomplete.

The Tribe

Like most other species, humans have always lived in groups. Group life enhances survivability by providing a collective form of protection and shelter against enemies and abrupt changes in the surroundings. But at some point in their evolutionary history—probably around 100,000 years ago—bipedal hominids had become so adept at tool-making, communicating, and thinking in symbols that they became consciously aware of the advantages of a group life based on a common system of representational activities. By around 30,000 to 40,000 years ago, the archeological evidence suggests, in fact, that hominid groups became increasingly characterized by communal customs, language, and the transmission of technological knowledge to subsequent generations. Anthropologists have designated this form of group life tribal.
The tribal form of social life has not disappeared from the human story. It has left its "archetypal" influence in the human psyche. In our view, this is the reason why the tribe remains the type of collectivity to which human beings instinctively relate even in modern times. In complex city-societies, where various cultures, subcultures, countercultures, and parallel cultures exist in constant competition with each other, where the shared territory is so large that it constitutes a mere abstraction, the tendency for individuals to relate to tribal-type groupings that exist within the larger societal context manifests itself regularly. People continue to perceive their membership in smaller groups as more directly meaningful to their lives than allegiance to the larger society and/or nation. This inclination towards tribalism, as Marshall McLuhan (1911-1980) emphasized, reverberates constantly within modern-day humans, and may be the source of the angst and sense of alienation that many modern-day city-dwelling individuals feel, living as they do in large, impersonal social systems.

Source: Analyzing cultures: an introduction and handbook / Marcel Danesi and Paul Perron. Bloomington : Indiana University Press, c1999