Cal skeleton, also as
rectus capitisventralis) would have had order WP1066 higher mechanical benefit. The length and size of these occipital characteristics recommend that massive purchase NSC309132 muscle tissues with augmented lever arms had been anchored to the azhdarchid skull. Witmer et al. (2003) and Habib Godfrey (2010) produced related observations about the occipital regions of other pterodactyloids: at least the anterior neck skeleton of pterosaurs was most likely strongly muscled. In the other intense in the axial column, the azhdarchid scapulocoracoid suggests that their superficial neck musculature may perhaps have been well created. Azhdarchid scapulocoracoids articulated tightly using the dorsal vertebrae and sternum (Frey, Buchy Martill, 2003) and were buried inside deep flight musculature, so were likely capable of small, if any, motion. Contraction of cervical-pectoral muscle groups would thus most likely elevate the neck, and asymmetric contraction of these muscles would move the neck laterally. These muscle tissues (or homologues thereof) are especially massive in long-necked, large-headed mammals including horses and deer (Goldfinger, 2004.Cal skeleton, too as in neighbouring cranial or torso skeletal components; this was certainly linked together with the anchoring of strong neck musculature and big ligaments in the base and anterior end of the neck. They are optimal positions from which to help and operate long necks. In view of this, the elongate and tubular, reasonably immobile mid-series vertebrae of azhdarchids need to be viewed as a pronounced development of a skeletal adaptation common across tetrapods, not as an uncommon or unprecedented anatomical configuration. Azhdarchid skeletons show ample attachment web pages for neck musculature. As an example, the occiput of Hatzegopteryx shows apparent indicators of substantial soft-tissue attachment: the nuchal line is well developed and extended, and its dorsolateral edges are deeply dished andNaish and Witton (2017), PeerJ, DOI 10.7717/peerj.17/marked with vertical scarring (Buffetaut, Grigorescu Csiki, 2002; Buffetaut, Grigorescu Csiki, 2003). Comparison with extant reptile anatomy Herrel De Vree, 1999; Cleuren De Vree, 2000; Tsuihiji, 2005; Tsuihiji, 2010; Snively Russell, 2007; Snively et al., 2014 suggests that these options reflect huge insertion places for transversospinalis musculature (specifically m. transversospinalis capiti along with the m. epistropheo-capitis/splenius group), cervical musculature devoted to head and neck extension and lateral flexion. The significant neural spines on posterior azhdarchid cervicals and anterior thoracic vertebrae present potential origin web pages for m. transversospinalis capiti, whilst the extended neural spine of cervical III likely anchored m. epistropheo-capitis. The opisthotic procedure of Hatzegopteryx is poorly known but was evidently huge and robust and probably facilitated attachment of large neck extensors and lateral flexors (m. semispinalis capitis/spinocapitis posticus). Similarly, the broken basioccipital tuberosities of Hatzegopteryx are long even as preserved: neck and head flexors anchoring to these (m. longissimus capitis profundus, m. rectus capitisventralis) would have had high mechanical advantage. The length and size of those occipital capabilities suggest that huge muscle tissues with augmented lever arms were anchored towards the azhdarchid skull. Witmer et al. (2003) and Habib Godfrey (2010) produced comparable observations about the occipital regions of other pterodactyloids: no less than the anterior neck skeleton of pterosaurs was probably strongly muscled. In the other extreme with the axial column, the azhdarchid scapulocoracoid suggests that their superficial neck musculature may perhaps have been nicely created. Their scapulae are substantial and dorsoventrally expanded compared to these of other pterosaurs (e.g., Elgin Frey, 2011), permitting broad insertions of m. levator scapulae and m.