Miller-Urey (1953): CH4 + NH3 + H2 + H2O + electric discharge (no O2) → amino acids; supports Oparin-Haldane chemical evolution hypothesis; reducing atmosphere is essential.

Homologous = same origin, different function → divergent evolution (forelimbs of whale/bat/horse/human; thorns of Bougainvillea + tendrils of Cucurbita); Analogous = different origin, same function → convergent evolution (bat wing + butterfly wing; octopus eye + mammal eye).

Hardy-Weinberg: p + q = 1 and $p^{2}$ + 2pq + $q^{2}$ = 1; FIVE conditions (no mutation, migration, selection; large population; random mating); standard calculation: $q^{2}$ → q → p → 2pq for carrier frequency.

Natural Selection types: Stabilizing (favours intermediate, reduces variation); Directional (shifts mean to one extreme, e.g., industrial melanism); Disruptive (favours both extremes, may cause speciation). Allopatric speciation = geographic isolation; Sympatric = polyploidy; Adaptive radiation = one ancestor, many niches (Darwin's finches, Australian marsupials).

Human Evolution (D-R-A-H-E-S): Dryopithecus (15 mya, ape) → Ramapithecus (14 mya) → Australopithecus (5 mya, first biped, 400-500 cc) → Homo habilis (2 mya, first tools, 600-700 cc) → Homo erectus (1.5 mya, fire + out of Africa, 800-1100 cc) → Homo sapiens (0.2 mya, language, 1300-1400 cc).