Dataset Information

The endocranial anatomy of therizinosauria and its implications for sensory and cognitive function.

ABSTRACT:

Background

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 particularly rare.

Methodology/principal findings

Based 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/significance

This 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.

SUBMITTER: Lautenschlager S

PROVIDER: S-EPMC3526574 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Publications

The endocranial anatomy of therizinosauria and its implications for sensory and cognitive function.

Lautenschlager Stephan S Rayfield Emily J EJ Altangerel Perle P Zanno Lindsay E LE Witmer Lawrence M LM

PloS one 20121219 12

<h4>Background</h4>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 r ...[more]

PMID: 23284972

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Dataset Information

The endocranial anatomy of therizinosauria and its implications for sensory and cognitive function.

Background

Methodology/principal findings

Conclusion/significance

Publications

The endocranial anatomy of therizinosauria and its implications for sensory and cognitive function.

Similar Datasets

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