Cal skeleton, too as

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epistropheo-capitis. The opisthotic method of Hatzegopteryx is poorly recognized but was evidently big and robust and most likely facilitated attachment of massive 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. MedChemExpress ZM241385 rectus capitisventralis) would have had higher mechanical benefit. The length and size of these occipital options suggest that huge muscle tissues with augmented lever arms have been anchored for the azhdarchid skull. Witmer et al. (2003) and Habib Godfrey (2010) made equivalent observations about the occipital regions of other pterodactyloids: at the least the anterior neck skeleton of pterosaurs was likely strongly muscled. In the other intense from the axial column, the azhdarchid scapulocoracoid suggests that their superficial neck musculature could have been properly created. Their scapulae are substantial and dorsoventrally expanded in comparison with these of other pterosaurs (e.g., Elgin Frey, 2011), permitting broad insertions of m. levator scapulae and m. serratus (Bennett (2003) shows their most likely origin in other pterosaurs). These muscles originate on the anterior cervicals in modern reptiles and may function as neck elevators and retractors if the scapulae are immobile. Azhdarchid scapulocoracoids articulated tightly with all the dorsal vertebrae and sternum (Frey, Buchy Martill, 2003) and had been buried inside deep flight musculature, so had been likely capable of small, if any, motion. Contraction of cervical-pectoral muscle groups would thus probably elevate the neck, and asymmetric contraction of those muscle tissues would move the neck laterally. These muscle tissues (or homologues thereof) are specifically massive in long-necked, large-headed mammals which include horses and deer (Goldfinger, 2004.Cal skeleton, too as in neighbouring cranial or torso skeletal elements; this was surely linked with the anchoring of effective neck musculature and huge ligaments at the base and anterior finish of the neck. These are optimal positions from which to support and operate long necks. In view of this, the elongate and tubular, somewhat immobile mid-series vertebrae of azhdarchids really should be viewed as a pronounced improvement of a skeletal adaptation frequent across tetrapods, not as an uncommon or unprecedented anatomical configuration. Azhdarchid skeletons show ample attachment web-sites for neck musculature. One example is, the occiput of Hatzegopteryx shows obvious signs of substantial soft-tissue attachment: the nuchal line is properly developed and extended, and its dorsolateral edges are deeply dished andNaish and Witton (2017), PeerJ, DOI ten.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 attributes reflect significant insertion regions for transversospinalis musculature (particularly m. 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 higher mechanical benefit. The length and size of these occipital options suggest that significant muscles with augmented lever arms were anchored for the azhdarchid skull. Witmer et al. (2003) and Habib Godfrey (2010) made equivalent observations concerning the occipital regions of other pterodactyloids: a minimum of the anterior neck skeleton of pterosaurs was most likely strongly muscled.