Over successive generations, heritable traits in the biological population change due to evolution. Here comes the meaning of cultural and biological evolution. Biology and culture developed side by side in human evolution. Biology makes culture possible, and culture then influences the direction of evolution. This concept helps us understand the significant and distinctive ideas of human evolution. Biological and cultural factors included in human evolution are also why it is also Biocultural Evolution.
The Cultural Factors in Human Evolution
A cultural change characterises each biological change in human evolution. The cerebral cortex of the brain helps in thinking and communication. So, changes in these parts affect the community and cultural life. For example, Food Gathering helped in the development of the frontal lobe. This part of the brain is responsible for problem-solving and motor control.
Toolmaking and Technology
Toolmaking is also a key area with cultural and biological changes in humans. The start of the cultural revolution enabled human beings to make tools and design them specifically. Followed by this was hunting and gathering of food. These activities engage different brain parts: the occipital lobe involves sight and perception required for sharp hunting, and the erect structure and bipedalism accomplished the use of tools and their making.
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Family and Community Building
If we take the example of the reproductive system, the enlarged brain of humans resulted in the widening of the hip region and the enlargement of the pubic region. Thus, the gestation period becomes longer. The prolonged infant-parent dependency helps in improving the bond between parent and child, leading to the strengthening of familial bonds and thus forming communities.
Linguistic and Symbolic Skills
Also, the linguistic ability in humans is mainly characterised by the Frontal lobe and the Temporal lobe. The development of language is why these brain parts show significant evolutionary changes. Symbolic measures and communication skills stemmed from the development of these areas. This cultural evolution helps form communities and the origin of civilisations.
The biological and cultural changes in human evolution are thus interlinked to a certain level. Cultural development was faster and steady compared to biological changes. The major difference in cultural and biological changes in human evolution involves genetic material. But the co-evolution of humans in such a way has qualified us to live a better and more adaptable life. Culture can thus have a substantial impact on gene frequencies, sometimes increasing and decreasing the rate of evolution.
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How are Biological and Cultural Factors Linked?
The biological factors of human evolution are noted by the journey from Hominid to Hominoid. This journey is complex and includes structural, behavioural, biological, and cultural changes. The prominent biological factors include –
Bipedalism and Erect Posture
Over time, our ancestors became bipedal, which means that we started walking using two legs. Their postures become upright as a result of the enlarging of the vertebra. The pelvic region becomes short and girdle. Convergent big toes and the platform feet helped them to walk by feet. The backward curving of the spine helped adjust the body weight in the pelvic area by increasing the number of sacrum bones. The flattening of ischium aids in the sitting position, which allowed the ancestors to be better hunters and gatherers.
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Expansion and Development of Brain
An evolutionary process helped the adaptive pressure shorten the brain’s size beyond a certain limit. Still, a steady increase was seen in the size of human brains since our ancestors, Australopithecus. The small and shortened size of the brain creates space for cranial expansion. This change happened because of the development of new cells as they started thinking and using language. The development of tools and stone weapons helped accelerate this process. The brain capacity of Australopithecus was 450 cc compared to the 1400 cc of Modern-day man. This change took place right after bipedalism.
Remodelling of Face and Teeth
The jaw and teeth become smaller. The forehead became vertical, and the noses protruded outside. The size of canines and incisors becomes reduced as the mastication requirement changes over time. The palate becomes shortened. The drastic changes in teeth directly affect the digestive system as now human beings can be omnivores. The Foramen magnum is now located at the centre of the skull’s base, with the head balancing nicely on the vertebral column.
All these changes have collectively influenced our evolutionary patterns. Cultural factors are thus bent so that they can influence and pressure the cultural life of humans. These principles occur in the cultural form of evolution in more complex forms than biological ones. The biological and cultural factors in human evolution, meaning co-evolution, help better the species as a whole and are closely related to the Darwinian theories of evolution.