| Species (N=917) | GC (%) | AT (%) | G (bases) | C (bases) | A (bases) | T (bases) | Maximum lifespan (yrs) |
|---|---|---|---|---|---|---|---|
| Tamandua tetradactyla | 34.8 | 65.2 | 58 | 13 | 47 | 86 | 19.0 |
| Tamias sibiricus | 30.9 | 69.1 | 50 | 13 | 61 | 80 | 9.6 |
| Tarentola mauritanica | 46.1 | 53.9 | 60 | 16 | 35 | 54 | 14.0 |
| Tarsius bancanus | 29.4 | 70.6 | 51 | 9 | 63 | 81 | 16.3 |
| Tarsius syrichta | 30.4 | 69.6 | 50 | 12 | 66 | 76 | 16.0 |
| Taurotragus derbianus | 32.8 | 67.2 | 50 | 16 | 53 | 82 | 20.3 |
| Taxidea taxus | 30.9 | 69.1 | 50 | 13 | 60 | 81 | 25.0 |
| Testudo graeca | 37.4 | 62.6 | 55 | 10 | 36 | 73 | 127.0 |
| Testudo kleinmanni | 37.7 | 62.3 | 58 | 11 | 35 | 79 | 21.0 |
| Testudo marginata | 38.5 | 61.5 | 55 | 12 | 36 | 71 | 21.2 |
| Tetracerus quadricornis | 30.9 | 69.1 | 51 | 12 | 59 | 82 | 17.4 |
| Tetrastes bonasia | 40.6 | 59.4 | 57 | 10 | 43 | 55 | 7.2 |
| Theropithecus gelada | 36.7 | 63.3 | 65 | 11 | 49 | 82 | 36.0 |
| Thraupis episcopus | 45.8 | 54.2 | 64 | 13 | 41 | 50 | 9.5 |
| Threskiornis aethiopicus | 42.9 | 57.1 | 62 | 10 | 41 | 55 | 37.0 |
| Thryonomys swinderianus | 30.3 | 69.7 | 50 | 9 | 55 | 81 | 5.4 |
| Thunnus alalunga | 45.2 | 54.8 | 56 | 20 | 36 | 56 | 13.0 |
| Thunnus albacares | 45.2 | 54.8 | 56 | 20 | 36 | 56 | 9.0 |
| Thunnus maccoyii | 45.2 | 54.8 | 56 | 20 | 36 | 56 | 20.0 |
| Thunnus obesus | 45.2 | 54.8 | 56 | 20 | 36 | 56 | 11.0 |
| Thunnus thynnus | 45.2 | 54.8 | 56 | 20 | 36 | 56 | 15.0 |
| Thymallus arcticus | 47.0 | 53.0 | 55 | 24 | 42 | 47 | 18.0 |
| Tomistoma schlegelii | 38.9 | 61.1 | 51 | 12 | 46 | 53 | 24.7 |
| Trachemys scripta | 32.8 | 67.2 | 50 | 12 | 54 | 73 | 41.3 |
| Trachypithecus cristatus | 30.0 | 70.0 | 52 | 10 | 63 | 82 | 28.3 |
| Trachypithecus francoisi | 28.0 | 72.0 | 49 | 9 | 64 | 85 | 26.3 |
| Trachypithecus johnii | 30.4 | 69.6 | 51 | 12 | 69 | 75 | 34.0 |
| Trachypithecus obscurus | 31.4 | 68.6 | 55 | 10 | 59 | 83 | 33.9 |
| Trachypithecus pileatus | 33.8 | 66.2 | 57 | 13 | 57 | 80 | 25.2 |
| Trachypithecus vetulus | 31.9 | 68.1 | 53 | 13 | 66 | 75 | 26.1 |
| Tragelaphus angasii | 29.4 | 70.6 | 47 | 12 | 59 | 83 | 18.5 |
| Tragelaphus eurycerus | 31.8 | 68.2 | 49 | 15 | 52 | 85 | 21.9 |
| Tragelaphus imberbis | 32.3 | 67.7 | 50 | 14 | 53 | 81 | 19.8 |
| Tragelaphus scriptus | 31.3 | 68.7 | 50 | 13 | 53 | 85 | 15.3 |
| Tragelaphus spekii | 31.8 | 68.2 | 50 | 14 | 52 | 85 | 22.6 |
| Tragelaphus strepsiceros | 31.3 | 68.7 | 50 | 13 | 51 | 87 | 23.5 |
| Tremarctos ornatus | 32.8 | 67.2 | 51 | 16 | 56 | 81 | 39.0 |
| Triaenodon obesus | 28.0 | 72.0 | 38 | 9 | 55 | 66 | 25.0 |
| Trichechus manatus | 36.3 | 63.7 | 60 | 14 | 63 | 67 | 65.0 |
| Trichiurus lepturus | 41.7 | 58.3 | 50 | 20 | 49 | 49 | 15.0 |