R necks have been neither weak nor underpowered.

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This appears appropriate offered the size from the Hatzegopteryx skull, and these features indicating huge muscle insertions on its occipital face.Naish and Witton (2017), PeerJ, DOI ten.7717/peerj.19/The holotype Study design and modification {of the|from cervical of Arambourgiania might also show some evidence of muscle scarring: a sagittal crest on its anterior ventral surface and two low crests around the dorsal surface on the prezygapophyses. The bifid neural spine of EME 315 is broken at the base of each and every procedure, but the broken surfaces are sufficiently broad and elongate (Fig. 1) to recommend that the spines have been broad, long and possibly tall when complete. The geometry on the zygapophyses are complex. Low crests and prominent edges extend from the vertebral corpus towards their articular surfaces, and their lateral and medial faces show complicated concavities and edges: we posit that these mark muscle scarring. The ventrolateral surfaces in the EME 315 corpus are also notably concave and meet the ventral face along a defined, sweeping edge. These capabilities recommend that EME 315 was well-muscled in life. This appears proper given the size with the Hatzegopteryx skull, and these features indicating significant muscle insertions on its occipital face.Naish and Witton (2017), PeerJ, DOI 10.7717/peerj.19/The holotype cervical of Arambourgiania may possibly also show some proof of muscle scarring: a sagittal crest on its anterior ventral surface and two low crests around the dorsal surface of your prezygapophyses. These latter features are topographically equivalent, although less defined, to crests seen on EME 315 along with other azhdarchid vertebrae. Having said that, the overall possible area for muscle attachment within this giant vertebra is substantially reduced than it can be in EME 315. The broken section with the anterior surface in the neural spine is smaller sized than that observed in EME 315, indicating a shallower neural spine overall. The zygapophyses are also shorter and much more gracile. These variations could be partly explained by the unique probably positions of EME 315 and UJA VF1 inside the cervical skeleton (a cervical V is expected to possess lesser muscle attachment than preceding or following vertebrae) but much better known azhdarchid necks recommend that generalities of morphology is going to be common in other, adjacent vertebrae along the column (Fig. five). We for that reason conclude that Arambourgiania probably had a relatively lightly muscled neck relative to that of Hatzegopteryx. That is in maintaining with all the decreased strength of UJA VF1 predicted in our testing.Disparity and ecological diversity in giant azhdarchidsEME 315 and the other Hatzegopteryx material offers the strongest evidence but that azhdarchids were not anatomically uniform (Vremir et al., 2013; Witton, 2013). Understanding the all round type of azhdarchids is hampered by a lack of linked material, but fragmentary specimens indicate that azhdarchids were variable in at the least 3 key anatomical respects (Figs. five and eight). The very first is neck type, because some taxa had fairly short (although probably not shorter than anticipated for other pterodactyloids), robust necks (like Hatzegopteryx; R2395), and other people had significantly longer, extra gracile and mechanically weaker necks (e.g., Quetzalcoatlus sp., Arambourgiania). The second is cranial morphotype: this also comprises robust types, with relatively brief skulls and proportionally broad jaws (e.g., the possible azhdarchid Bakonydraco; Javelina.