Human Evolution: Bipedalism, Language, and Cultural Development

Conditioning Factors in the Hominization Process

Friedrich Engels, in his work The Role of Work in the Transformation from Ape to Man, explains the process of humanization, noting four defining characteristics.

One of the primary elements that led a group of hominoids to become hominids was bipedalism (standing upright), which enabled the development of an arch on the soles of the feet, while the upper limbs became shorter than the lower. Similarly, the center of gravity shifted backward, encouraging skull transformation. The foramen magnum (the opening in the skull base through which the spinal cord passes) moved from the back to the central part of the skull base. The architecture of the face and jaw also modified, with prognathism disappearing.

Bipedal gait proved highly effective under these conditions because:

• Allows scanning the horizon above herbaceous vegetation in search of trees or predators.
• Allows transporting items (such as food, sticks, stones, or offspring) with hands freed from locomotor function.
• It is slower than quadrupedal walking but is less energy-intensive, which was advantageous for traveling long distances in the savanna or in forest habitats with fewer resources.
• Exposes less surface area to the sun and can take advantage of breezes, helping the body avoid overheating and conserve water, a crucial advantage in water-scarce habitats.

This release of the upper limbs was, in the beginning, an optimal adaptation to the savanna biome. With their arms freed by bipedalism, the ancestors of humans could more easily collect food such as roots, fruits, leaves, insects, eggs, small reptiles, rodents, and carrion. In fact, many indications suggest our ancestors were largely scavengers, often practicing a modality called kleptoparasitism.

Psychosocial Transformations

Human beings are social animals. Early hominid societies primarily functioned to protect individuals. Group activities benefit the individual. Planned behavior develops from experience, making knowledge accumulation within the group essential.

Emergence of Language

Language emerges from the complexity of hominid behavior. As the psyche evolves, a more complex language and verbal communication become necessary. The word becomes the core of social experience, enabling the acquisition and transmission of knowledge.

Functions of Culture

• Socialize individuals from childhood in accordance with their particular class subculture.
• Determine the opportunities individuals will have throughout their lives.
• Distribute privileges and social responsibilities.
• Present the real possibilities of social mobility between classes in an open system of stratification.