Table 10. Muscle and limb masses in select amniotes.
| Genus | Refs | Mbody (kg) | Clade | Sampled Limb | Mextensor / Mbody (%) | Mmusc /Mbody (%) | Mlimb / Mbody (%) |
| Gecko | [88] | 0.057 | Squamata | Pelvic | 5.1 | 17 | |
| Basiliscus | [67] | 0.191 | Squamata | Pelvic | 6.9 | 19 | 26+ |
| Iguana | [67] | 4.04 | Squamata | Pelvic | 2.5 | 6 | 15+ |
| Alligator | [54], [67] | 10 | Crocodylia | Pelvic | 5.4 | 15 | 9.7+ |
| Coturnix | [87] | 0.095 | Aves | Pelvic | 5.5 | 11 | |
| Pica | [89] | 0.22 | Aves | Pelvic | 2.8 | 7 | 18 |
| Eudromia | [67] | 0.406 | Aves | Pelvic | 4.2 | 11 | 19 |
| Numida | [90], [91] | 1.47 | Aves | Pelvic | 9.1 | 23 | 27 |
| Gallus (junglefowl) | [84] | 1.94 | Aves | Pelvic | 6.6 | 16 | |
| Meleagris | [67] | 3.7 | Aves | Pelvic | 5.5 | 12 | 20 |
| Dromaius | [67] | 27.2 | Aves | Pelvic | 14.5* | 28 | 41 |
| Struthio | [67] | 65.3 | Aves | Pelvic | 10.5 | 26 | 38 |
| Lepus | [92], [93], [98] | 3.45 | Mammalia | Pect+Pelv | 10.2 | 27 | 29 |
| Macropus 1 | [67], [86] | 6.6 | Mammalia | Pelvic | 9.1 | 22 | 36 |
| Macropus 2 | [86] | 10.5 | Mammalia | Pelvic | 9.6 | 22 | |
| Canis (greyhound) | [94], [95] | 31.6 | Mammalia | Pect+Pelv | 12.5 | 36 | 33 |
| Acinonyx | [96], [97] | 33.1 | Mammalia | Pect+Pelv | 11.2 | 32 | 40 |
| Pan | [99], [100] | 54.6 | Mammalia | Pect+Pelv | 11.6 | 32 | 40 |
| Homo | [67] | 71 | Mammalia | Pelvic | 9.5 | 9 | 39 |
| Equus | [85], [101]–[103] | 510 | Mammalia | Pect+Pelv | 10.0 | 28 | 30 |
| Giraffa | JRH | 684.5 | Mammalia | Pect+Pelv | 11.3 | 32 | |
| Hippopotamus | JRH | 1600 | Mammalia | Pect+Pelv | 7.3 | 21 | |
| Ceratotherium | JRH | 1755 | Mammalia | Pect+Pelv | 6.8 | 20 | |
| Elephas | JRH | 3550 | Mammalia | Pect+Pelv | 6.7 | 20 | 27.7 |
| Tyrannosaurus rex | This Study | 5934–18611 | Tyrannosauridae | Pelvic | ≤14.6–25.4 | ? | 35–65 |
| Mean | 8.1 | 20 | 29 | ||||
| SD | 3.1 | 8.5 | 9.6 | ||||
“Refs” lists the literature source for the data; “JRH” indicates specimens from author JRH's personal collection, from single musculoskeletally sound zoo-sourced adult specimens, and are otherwise unpublished data. “Sampled Limb” indicates which limbs data are shown for; in particular note that only pelvic limb data are available for the first four quadrupedal taxa. “Mbody” shows the body mass (or mean for multiple specimens). “Mextensor / Mbody” shows the percentage of whole body mass dedicated to sampled extensor muscles (one hindlimb only, and one forelimb if available). “Mmusc /Mbody” shows the percentage of body mass dedicated to limb musculature (one hindlimb only, and one forelimb if available). “Mlimbs / Mbody” shows the percentage of body mass that the sampled limb mass (for left and right limbs) constitutes. 1 Red kangaroo (Macropus rufus). 2 Bennet's wallaby (Macropus rufogriseus).
*Note that these data are for one individual and it is far from conclusive that, as the table might imply, emus have larger leg muscles than ostriches; it could merely be caused by individual variation and measurement error. The Tyrannosaurus data shown are the upper end (over)estimates for all four adult models (Tables 5,6,9), showing the range of values from minimal and maximal models. Mean and standard deviation (SD) values at bottom exclude Tyrannosaurus.