| Species (N=917) | GC (%) | AT (%) | G (bases) | C (bases) | A (bases) | T (bases) | Maximum lifespan (yrs) |
|---|---|---|---|---|---|---|---|
| Coregonus nasus | 48.8 | 51.2 | 59 | 23 | 39 | 47 | 15.0 |
| Corvus brachyrhynchos | 41.1 | 58.9 | 60 | 9 | 42 | 57 | 20.0 |
| Corvus cornix | 41.7 | 58.3 | 60 | 10 | 40 | 58 | 16.8 |
| Corvus frugilegus | 41.1 | 58.9 | 61 | 8 | 41 | 58 | 22.9 |
| Corvus hawaiiensis | 42.3 | 57.7 | 61 | 10 | 42 | 55 | 25.0 |
| Cottus poecilopus | 47.6 | 52.4 | 59 | 21 | 39 | 49 | 8.0 |
| Coturnix chinensis | 41.1 | 58.9 | 57 | 12 | 38 | 61 | 5.0 |
| Coturnix japonica | 38.1 | 61.9 | 56 | 8 | 37 | 67 | 6.0 |
| Crax rubra | 41.8 | 58.2 | 58 | 11 | 38 | 58 | 24.0 |
| Crocidura russula | 32.4 | 67.6 | 54 | 12 | 58 | 80 | 4.0 |
| Crocodylus acutus | 34.0 | 66.0 | 42 | 13 | 40 | 67 | 32.9 |
| Crocodylus intermedius | 32.7 | 67.3 | 42 | 11 | 40 | 69 | 21.8 |
| Crocodylus moreletii | 34.0 | 66.0 | 41 | 14 | 41 | 66 | 25.4 |
| Crocodylus niloticus | 35.2 | 64.8 | 43 | 14 | 39 | 66 | 43.8 |
| Crocodylus novaeguineae | 37.0 | 63.0 | 48 | 12 | 35 | 67 | 24.6 |
| Crocodylus palustris | 37.7 | 62.3 | 43 | 18 | 40 | 61 | 31.5 |
| Crocodylus porosus | 39.5 | 60.5 | 48 | 16 | 38 | 60 | 41.7 |
| Crocodylus rhombifer | 32.1 | 67.9 | 39 | 13 | 43 | 67 | 38.2 |
| Crocodylus siamensis | 38.9 | 61.1 | 48 | 15 | 38 | 61 | 21.9 |
| Crocuta crocuta | 37.3 | 62.7 | 64 | 12 | 43 | 85 | 41.1 |
| Crotalus horridus | 36.4 | 63.6 | 51 | 9 | 34 | 71 | 30.2 |
| Ctenopharyngodon idella | 40.6 | 59.4 | 48 | 19 | 36 | 62 | 21.0 |
| Culaea inconstans | 34.5 | 65.5 | 44 | 14 | 57 | 53 | 2.0 |
| Cuon alpinus | 38.2 | 61.8 | 59 | 19 | 56 | 70 | 16.1 |
| Cuora amboinensis | 35.1 | 64.9 | 44 | 15 | 45 | 64 | 38.2 |
| Cuora flavomarginata | 35.7 | 64.3 | 47 | 13 | 44 | 64 | 19.1 |
| Cuora trifasciata | 35.1 | 64.9 | 46 | 13 | 44 | 65 | 31.8 |
| Cyclemys dentata | 32.1 | 67.9 | 43 | 11 | 47 | 67 | 14.7 |
| Cycleptus elongatus | 38.1 | 61.9 | 43 | 21 | 46 | 58 | 13.0 |
| Cygnus columbianus | 44.0 | 56.0 | 63 | 11 | 33 | 61 | 24.1 |
| Cygnus cygnus | 44.6 | 55.4 | 62 | 13 | 34 | 59 | 26.5 |
| Cygnus olor | 42.9 | 57.1 | 59 | 13 | 38 | 58 | 70.0 |
| Cymatogaster aggregata | 41.7 | 58.3 | 49 | 21 | 47 | 51 | 8.0 |
| Cynomys ludovicianus | 32.4 | 67.6 | 53 | 13 | 66 | 72 | 11.0 |
| Cynopterus brachyotis | 34.8 | 65.2 | 57 | 14 | 56 | 77 | 10.1 |
| Cyprinella lutrensis | 40.1 | 59.9 | 47 | 18 | 41 | 56 | 2.0 |
| Cyprinella spiloptera | 40.6 | 59.4 | 46 | 21 | 44 | 54 | 5.0 |
| Cyprinus carpio | 35.8 | 64.2 | 40 | 19 | 48 | 58 | 47.0 |
| Daboia russellii | 30.9 | 69.1 | 41 | 10 | 51 | 63 | 15.0 |
| Dactylopsila trivirgata | 33.8 | 66.2 | 56 | 15 | 61 | 78 | 9.6 |