Abstract
BackgroundTherizinosauria is one of the most enigmatic and peculiar clades among theropod dinosaurs, exhibiting an unusual suite of characters, such as lanceolate teeth, a rostral rhamphotheca, long manual claws, and a wide, opisthopubic pelvis. This specialized anatomy has been associated with a shift in dietary preferences and an adaptation to herbivory. Despite a large number of discoveries in recent years, the fossil record for Therizinosauria is still relatively poor, and cranial remains are particularly rare.Methodology/Principal FindingsBased on computed tomographic (CT) scanning of the nearly complete and articulated skull of Erlikosaurus andrewsi, as well as partial braincases of two other therizinosaurian taxa, the endocranial anatomy is reconstructed and described. The wider phylogenetic range of the described specimens permits the evaluation of sensory and cognitive capabilities of Therizinosauria in an evolutionary context. The endocranial anatomy reveals a mosaic of plesiomorphic and derived characters in therizinosaurians. The anatomy of the olfactory apparatus and the endosseous labyrinth suggests that olfaction, hearing, and equilibrium were well-developed in therizinosaurians and might have affected or benefited from an enlarged telencephalon.Conclusion/SignificanceThis study presents the first appraisal of the evolution of endocranial anatomy and sensory adaptations in Therizinosauria. Despite their phylogenetically basal position among maniraptoran dinosaurs, therizinosaurians had developed the neural pathways for a well developed sensory repertoire. In particular olfaction and hearing may have played an important role in foraging, predator evasion, and/or social complexity.
Highlights
Therizinosauria comprises an enigmatic clade of Cretaceous (Barremian – Maastrichtian) maniraptoran dinosaurs found in Asia and North American [1]
Conclusion/Significance: This study presents the first appraisal of the evolution of endocranial anatomy and sensory adaptations in Therizinosauria
The individual parts of the brain are arranged in the same horizontal plane and do not show an obvious angulation, indicating only slight cephalic and pontine flexures. This is in contrast to more basal theropods, where the angulation of the midbrain can be up to 45–60 degrees [20,21,22], and in contrast to the endocast of the holotype of Falcarius utahensis (UMNH VP 15000)
Summary
Therizinosauria comprises an enigmatic clade of Cretaceous (Barremian – Maastrichtian) maniraptoran dinosaurs found in Asia and North American [1] They are distinguished from other theropods by an unusual suite of morphological characters, which include lanceolate, tightly packed teeth, a rostral rhamphotheca, an elongate neck, enlarged manual claws, and a wide, opisthopubic pelvis. Therizinosauria is one of the most enigmatic and peculiar clades among theropod dinosaurs, exhibiting an unusual suite of characters, such as lanceolate teeth, a rostral rhamphotheca, long manual claws, and a wide, opisthopubic pelvis This specialized anatomy has been associated with a shift in dietary preferences and an adaptation to herbivory. Despite a large number of discoveries in recent years, the fossil record for Therizinosauria is still relatively poor, and cranial remains are rare
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
