What cranial feature does *Xiaotingia*'s shallow snout align it morphologically closer to, rather than basal avialans like *Jeholornis*?
Features found in Deinonychosaurs
*Xiaotingia* possessed several key cranial characteristics, including a large orbit and a notably shallow snout, which resulted in a distinctive sub-triangular lateral profile. This specific morphology, particularly the shallow and gracile skull structure, aligns it more closely with groups such as deinonychosaurs and *Archaeopteryx*. In contrast, other basal avialans mentioned, like *Epidexipteryx* or *Jeholornis*, tend to exhibit deeper and shorter snouts, a shape reminiscent of Oviraptorosaurs. The interpretation of this trait suggests that the gracile skull might represent the primitive, ancestral condition retained by Deinonychosauria, rather than a derived trait that was subsequently lost in the lineage leading directly to crown Aves.
