Part 1 Evolution by natural selection: Darwin's theory; evolution "in vitro"; Lamark, Weismann and the central dogma. Part 2 Models of populations: models of population growth; selection in an asexual population; the accuracy of replication; genetic drift in finite populations. Part 3 Evolution in diploid populations: gene frequencies and the Hardy-Weinberg ratio; the concept of fitness; the spread of a favourable gene. Part 4 The variability of natural populations: the evidence for genetic variability; mutation; the maintenance of variation. Part 5 Evolution at more than one locus: linkage disequilibrium; heterostyly in plants; mimicry in butterflies; linkage disequilibrium in natural populations; normalizing selection and linkage disequilibriums. Part 6 Quantitative genetics: nature and nurture; the additive genetic model; a more realistic model; experiments in artificial selection; quantitative variation and fitness; the maintenance of genetic variance for quantitative traits. Part 7 A model of phenotypic evolution: pairwise interactions; some extensions of the model; will a sexual population evolve to an ESS? Part 8 Finite and structured populations: inbreeding; genetic drift; the rate of neutral molecular evolution; mitochondrial DNA; migration and differentiation between populations; the establishment of a new favourable mutation. Part 9 Evolution in structured populations: selection in trait groups; the evolution of co-operation - synergistic selection, relatedness; the group as the unit of evolution; the shifting balance theory. Part 10 The evolution of prokaryotes: the evolution of gene function; phages, plasmids and transposable elements; the evolution of phages and their hosts, plasmids, transposons; the population genetics of "E. coli"; the evolution of viruses. Part 11 The evolution of the eukaryotic genome: the nature of the genome; the haemoglobin gene family; duplication and the increase of DNA content; the ribosomal gene; unequal crossing over and gene conversion; repetitive DNA; karyotypic evolution. Part 12 The evolution of genetic systems - sex and recombination: the natural history of eukaryotic sex; the evolutionary significance of sex; the evolution of recombination. Part 13 The evolution of genetic systems - some consequences of sex: the sex ratio; selfing and outcrossing; hermaphroditism; sexual selection. Part 14 Macroevolution: species and speciation; patterns of evolution; coevolution.