Biological/Physical Anthropology: Human Evolution, Primates, Variation and Adaptation
This domain tests human evolution, primate characteristics, and human biological variation and adaptation. Expect questions on hominin trends, primate classification, and why populations differ biologically without falling into racial typology.
Core concepts
Primates share grasping hands and feet, forward-facing eyes, nails instead of claws, large brains relative to body size, and extended parental care. Hominin evolution shows bipedalism, encephalization, reduced face and teeth, and culture. Key fossils include Australopithecus, early Homo, Homo erectus and Homo sapiens. Human variation is continuous and clinal: blood groups, haemoglobin variants and skin colour vary gradually, not as discrete races.
Adaptation includes genetic and developmental responses. Bergmann’s rule relates body size to temperature; Allen’s rule relates limb proportions to temperature. Sickle-cell trait persists where malaria is endemic because heterozygotes have an advantage. High-altitude populations show physiological adaptations to hypoxia.
Worked example
Why is dark skin common near the equator? Reasoning: strong ultraviolet radiation damages folate, while lighter skin aids vitamin D synthesis at high latitudes. Skin colour is thus a compromise shaped by UV exposure and migration, not a marker of discrete racial groups.
Traps that cost marks
Do not present evolution as a ladder ending in humans. Do not confuse Australopithecus with modern apes. Do not treat race as a biologically valid typology. Do not say all adaptations are genetic; acclimatization and developmental plasticity also matter. Distinguish primate from hominin traits.
Key points
- Primates: grasping limbs, forward eyes, nails, large brains, parental care.
- Hominin trends: bipedalism, larger brains, smaller teeth and faces.
- Human variation is clinal and continuous, not racial typology.
- Sickle-cell trait is a malaria-related balanced polymorphism.
- Bergmann’s and Allen’s rules concern body size and limb proportions.