Table 1. Midshaft humeral unstandardized properties of Zhoukoudian right humerus (III) and comparative samples.
| Length | Body Mass | TA | CA | %CA | Imax | Imin | Zmax | Zmin | J | Zp | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| (mm) | (kg) | (mm2) | (mm2) | (mm4) | (mm4) | (mm3) | (mm3) | (mm4) | (mm3) | |||
| Zhoukoudian IIIa,b | 307.4 −324.0 | 53.6 ± 1.7 | 250 | 167 | 66.8 | 5,959 | 3,307 | 579 | 415 | 9,266 | 875 | |
| KNM-ER 1,808c | 350.0 | 60.2 ± 20.4 | 240 | 197 | 82.1 | 5,212 | 3,891 | 503 | 457 | 9,103 | 877 | |
| Tianyuan 1a,d | 327.4 | 85.1 | 330 | 249 | 75.5 | 10,561 | 6,345 | 912 | 684 | 16,906 | 1,391 | |
| Middle Paleolithic Modern Humane (n = 4 for length, TA, CA, Ix, and Iy, n = 2 for body mass, n = 5 for Imax, Imin, and J) | Mean | 358.3 | 66.1 | 303.5 | 235.3 | 76.2 | 8,152 | 5,216 | – | – | 13,368 | – |
| S.D. | 20.5 | 3.9 | 80.5 | 81.3 | 7.4 | 4,452 | 2,985 | – | – | 7,395 | – | |
| Min | 329.0 | 63.3 | 190.7 | 130.0 | 68.2 | 3,591 | 1,946 | – | – | 5,537 | – | |
| Max | 375.0 | 68.8 | 381.4 | 327.4 | 85.8 | 14,567 | 8,834 | – | – | 23,401 | – | |
| Neanderthale (n = 12 for length, n = 9 for body mass, n = 12 for TA, CA, Ix, and Iy, n = 14 for Imax and Imin, n = 15 for J) | Mean | 301.6 | 71.5 | 314.8 | 244.5 | 77.8 | 9,373 | 5,444 | – | - | 14,945 | – |
| S.D. | 20.6 | 10.1 | 79.3 | 65.6 | 7.7 | 4,062 | 2,479 | – | – | 6,246 | – | |
| Min | 262.0 | 59.9 | 183.3 | 125.3 | 61.8 | 3,705 | 1,887 | – | – | 5,592 | – | |
| Max | 335.5 | 85.5 | 426.0 | 365.9 | 88.1 | 14,787 | 9,757 | – | – | 24,544 | – | |
| Early Upper Paleolithic Modern Humane (n = 17 for length, n = 13 for body mass, n = 14 for TA, CA, Ix, and Iy, n = 22 for Imax, Imin, and J) | Mean | 332.6 | 69.0 | 330.7 | 227.4 | 69.6 | 9,317 | 6,094 | – | – | 15,411 | – |
| S.D. | 25.9 | 7.8 | 73.4 | 48.6 | 9.2 | 3,558 | 2,253 | – | – | 5,716 | – | |
| Min | 284.0 | 55.7 | 181.5 | 143.0 | 52.4 | 3,210 | 2,207 | – | – | 5,417 | – | |
| Max | 371.0 | 82.5 | 444.2 | 316.8 | 91.1 | 17,592 | 10,579 | – | – | 27,736 | – | |
| East Eurasia Late Upper Paleolithic Modern Humane (n = 9 for length, n = 8 for body mass, n = 10 for TA, CA, Ix, Iy, Imax, Imin, and J) | Mean | 274.3 | 51.4 | 232.1 | 172.5 | 74.7 | 5,612 | 2,937 | – | – | 8,549 | |
| S.D. | 18.1 | 9.9 | 30.5 | 18.7 | 5.1 | 1,570 | 774 | – | – | 2,251 | ||
| Min | 252.0 | 42.3 | 189.5 | 153.6 | 66.5 | 3,671 | 2,132 | – | – | 5,803 | ||
| Max | 311.0 | 70.5 | 283.1 | 218.0 | 84.6 | 8,331 | 4,486 | – | – | 12,817 | ||
| Datong (n = 10)f | Mean | 305.8 | – | 308 | 193 | 62.8 | 8,660 | 5,360 | 742 | 548 | 14,020 | 1,143 |
| S.D. | 18.2 | – | 69 | 46 | 5.7 | 3,743 | 2,254 | 251 | 196 | 5,951 | 395 | |
| Min | 272.4 | – | 210 | 131 | 54.4 | 4,134 | 2,166 | 401 | 307 | 6,336 | 601 | |
| Max | 328.0 | – | 397 | 258 | 69.0 | 14,107 | 8,751 | 1,072 | 831 | 22,858 | 1,715 | |
| Junziqing (n = 23)f | Mean | 286.2 | – | 268 | 161 | 59.7 | 6,199 | 3,958 | 565 | 451 | 10,157 | 915 |
| S.D. | 17.5 | – | 50 | 44 | 10.8 | 2,514 | 1,663 | 190 | 143 | 4,132 | 308 | |
| Min | 262.9 | – | 193 | 90 | 42.9 | 2,678 | 1,722 | 288 | 255 | 4,632 | 497 | |
| Max | 327.7 | – | 384 | 243 | 78.8 | 11,814 | 7,540 | 988 | 738 | 18,877 | 1,571 |
Notes.
Estimated cross section location due to incomplete length.
Maximum length of the left Zhoukoudian Humerus II was reported by Weidenreich (1941) to be 324.0 mm. We estimated maximum length as 307.4 mm using a regression analysis of the distance between the deltoid tuberosity and the proximal margin of the olecranon fossa against maximum length on our comparative sample of Datong and Junziqing modern Homo sapiens (n = 33; see Text S4). In order to be conservative, we use both estimates to provide a range of standardized values for Zhoukoudian humeri about a mean value (315.7 mm). In order to standardize cross-sectional properties, we used maximum length estimates of the reconstructed left Zhoukoudian Humerus II as proxies for maximum length estimates of the partial right Zhoukoudian Humerus III.
Cross-sectional data for a 40% length section published by Ruff (2008: Fig. 1). We used a rough approximation of 350.0 mm for humeral length (Ruff, 2008; C Ruff, pers. comm., 2016).
In order to standardize cross-sectional properties, but acknowledging substantial bilateral asymmetry in their cross-sectional properties, we chose to use biomechanical length of the left Tianyuan 1 humerus (327.4 mm: Shang & Trinkaus, 2010) as a proxy for length of the right Tianyuan 1 humerus.
Data from Churchill (1994), Trinkaus, Churchill & Ruff (1994), Trinkaus & Churchill (1999), Crevecoeur (2008), and Sparacello et al. (2017).
Amongst the recent modern human comparative sample, the distal-most point of the deltoid tuberosity was between 43 and 53% shaft length, with the majority of specimens falling between 46 and 51%.