Figure 1. Sites of major forms of DNA damage. Adapted from Lindahl (1993).

Figure 2. The products of deamination of the four major bases.

Figure 3. Base adducts formed in DNA as a result of (a) oxidation, (b) alkylation and (c) formation of cyclic addition via a base propenal.

Figure 4. Schematic representation of the two major repair pathways: (a) base excision repair and (b) nucleotide excision repair.

Figure 5. Some extinct organisms from which DNA sequences have been determined (bottom left to top right): quagga, marsupial wolf, sabre-toothed cat, moa, mammoth, cave bear, blue antelope, giant ground sloth, aurochs, mastodon, New Zealand coot, South Island piopio, Steller's sea cow, Neanderthal, Aptornis defossor, Shasta ground sloth, pig-footed bandicoot, moa-nalo, Myotragus balearicus. Reproduced with permission from Hofreiter et al. (2001).

Figure 6. Schematic phylogenetic tree relating the mitochondrial DNAs of modern humans and three Neanderthals from Croatia, Caucasus and Germany. Reproduced with permission from Hofreiter et al. (2001)