Cal skeleton, as well as

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As an example, the occiput of Hatzegopteryx shows apparent signs 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 attributes reflect huge insertion places for transversospinalis musculature (particularly m. transversospinalis capiti as well as 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 supply potential origin web-sites for m. transversospinalis capiti, when the lengthy neural spine of cervical III probably anchored m. epistropheo-capitis. The opisthotic approach of Hatzegopteryx is poorly recognized but was evidently substantial and robust and probably facilitated attachment of massive neck extensors and lateral flexors (m. semispinalis capitis/spinocapitis posticus). Similarly, the broken basioccipital tuberosities of Hatzegopteryx are lengthy 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 features suggest that massive muscles with augmented lever arms had been anchored to the azhdarchid skull. Witmer et al. (2003) and Habib Godfrey (2010) produced related observations regarding the occipital regions of other pterodactyloids: at the least the anterior neck skeleton of pterosaurs was most likely strongly muscled. In the other intense from the axial column, the azhdarchid scapulocoracoid suggests that their superficial neck musculature may possibly have been well developed. Their scapulae are huge and dorsoventrally expanded in comparison to these of other pterosaurs (e.g., Elgin Frey, 2011), permitting broad insertions of m. serratus (Bennett (2003) shows their likely origin in other pterosaurs). These muscles originate on the anterior cervicals in contemporary reptiles and can function as neck elevators and retractors in the event the scapulae are immobile. Azhdarchid scapulocoracoids articulated tightly using the dorsal vertebrae and sternum (Frey, Buchy Martill, 2003) and had been buried within deep flight musculature, so had been likely capable of little, if any, motion. Contraction of cervical-pectoral muscle groups would hence probably elevate the neck, and asymmetric contraction of those muscle tissues would move the neck laterally. These muscle tissues (or homologues thereof) are ZM241385 manufacturer specifically massive in long-necked, large-headed mammals for instance horses and deer (Goldfinger, 2004.Cal skeleton, at the same time as in neighbouring cranial or torso skeletal elements; this was certainly related with the anchoring of strong neck musculature and large ligaments in the base and anterior end from the neck. They are optimal positions from which to help and operate long necks. In view of this, the elongate and tubular, comparatively immobile mid-series vertebrae of azhdarchids needs to be viewed as a pronounced improvement of a skeletal adaptation popular across tetrapods, not as an uncommon or unprecedented anatomical configuration. Azhdarchid skeletons show ample attachment web sites for neck musculature. As an example, the occiput of Hatzegopteryx shows obvious signs of substantial soft-tissue attachment: the nuchal line is effectively created and lengthy, 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).