Biological Anthropology and Human Evolution
What this domain tests
Biological anthropology covers evolution, genetics, primate behavior, the hominin fossil record, and biocultural adaptation. Exam items ask you to read a trait list, place a fossil, distinguish relative from absolute dating, and explain natural selection without Lamarckian shortcuts.
Core rules and concepts
- Natural selection acts on heritable variation within populations; it is not goal-directed and does not act for the good of the species.
- Bipedalism preceded brain expansion. Key indicators: anteriorly placed foramen magnum, shortened ilium, valgus knee, non-opposable big toe.
- Hominin sequence (approximate): Sahelanthropus ~7 Ma; Ardipithecus ~4.4 Ma; Australopithecus afarensis 3.9–3.0 Ma; Homo habilis ~2.4 Ma; H. erectus ~1.9 Ma; Neanderthals ~400–40 ka; H. sapiens ~300 ka.
- Dating: relative methods (stratigraphy, biostratigraphy, seriation) order things; absolute methods (radiocarbon, potassium-argon, U-series, thermoluminescence) give ages. Radiocarbon is limited to organic material younger than roughly 50,000 years.
- Race is a social category, not a valid biological subspecies; human genetic variation is clinal and mostly within populations.
Worked example
A fossil has an anterior foramen magnum, a short broad pelvis, a valgus knee, a cranial capacity of 450 cc, and is dated 3.2 Ma. Reasoning: the postcranial traits indicate habitual bipedalism; the small brain rules out Homo; the date and East African morphology fit Australopithecus afarensis. The specimen shows that upright walking was established long before large brains evolved.
Traps that cost marks
Saying humans evolved from chimpanzees (we share a common ancestor); invoking Lamarckian use and disuse; equating brain size with intelligence; using radiocarbon on volcanic rock; treating race as a biological unit.