Exemplar profiles of the distal ends of sauropod left humeri (anterior surfaces towards top).

<p>A, <i>Mamenchisaurus youngi</i> (ZDM 0083 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125819#pone.0125819.ref107" target="_blank">107</a>]); B, <i>Ferganasaurus</i> (PIN 3042/1 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125819#pone.0125819.ref101" target="_blank">101</a>]): C, <i>Apatosaurus excelsus</i> (YPM 1980 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125819#pone.0125819.ref100" target="_blank">100</a>]); D, <i>Camarasaurus grandis</i> (YPM 1901 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125819#pone.0125819.ref100" target="_blank">100</a>]); E, <i>Haestasaurus</i> (NHMUK R1870); F, <i>Giraffatitan</i> (MfN MB.R 2181 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125819#pone.0125819.ref087" target="_blank">87</a>]: a right humerus that has been reversed to facilitate comparison); G, <i>Epachthosaurus</i> (UNPSJB-PV 920, based on a photograph by PDM); H, <i>Diamantinasaurus</i> (AAOD 603 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125819#pone.0125819.ref080" target="_blank">80</a>]); I, <i>Neuquensaurus</i> (MLP-CS 1050 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125819#pone.0125819.ref090" target="_blank">90</a>]). Abbreviation: aep, anterior entepicondylar process. Profiles not drawn to the same scale.