Convergent avialan brain morphology in Sinovenator (Troodontidae, Theropoda) DOI Creative Commons
Congyu Yu, Akinobu Watanabe, Zichuan Qin

et al.

Research Square (Research Square), Journal Year: 2023, Volume and Issue: unknown

Published: Jan. 19, 2023

Abstract Multiple modifications to the skull and brain anatomy occurred along lineage encompassing bird-line theropod dinosaurs modern birds. Anatomical changes endocranium include an enlarged endocranial cavity, relatively larger optic lobe that implies elevated visual acuity, proportionately smaller olfactory bulbs suggests reduced olfaction. Here, we use micro-computed tomographic (CT) imaging reconstruct its structures from exceptionally well-preserved of Sinovenator changii (Troodontidae, Theropoda). While overall morphology resembles typical other troodontids, also exhibits unique features are similar paravian taxa non-maniraptoran theropods. Landmark-based geometric morphometric analysis on shape non-avialan avian points most closely resembling Archaeopteryx , thus indicating convergent evolution avialan in troodontids wide existence such architecture Maniraptora. Institutional abbreviations : IVPP Institute Vertebrate Paleontology Paleoanthropology, Chinese Academy Sciences, Beijing 100044, China. PMOL Paleontological Museum Liaoning, Shenyang 110034,

Language: Английский

Avialan-like brain morphology in Sinovenator (Troodontidae, Theropoda) DOI Creative Commons
Congyu Yu, Akinobu Watanabe, Zichuan Qin

et al.

Communications Biology, Journal Year: 2024, Volume and Issue: 7(1)

Published: Feb. 10, 2024

Many modifications to the skull and brain anatomy occurred along lineage encompassing non-avialan theropod dinosaurs modern birds. Anatomical changes endocranium include an enlarged endocranial cavity, relatively larger optic lobes that imply elevated visual acuity, proportionately smaller olfactory bulbs suggest reduced capacity. Here, we use micro-computed tomographic (μCT) imaging reconstruct its neuroanatomical features from exceptionally well-preserved of Sinovenator changii (Troodontidae, Theropoda). While overall morphology resembles typical other troodontids, also exhibits unique are similar paravian taxa non-maniraptoran theropods. Landmark-based geometric morphometric analysis on shape avialan points most closely resembling Archaeopteryx, thus indicating acquisition avialan-grade in troodontids wide existence such architecture Maniraptora.

Language: Английский

Citations

7
Paleoneurology of the iguanodontian Fostoria dhimbangunmal from the mid-Cretaceous of Australia DOI Creative Commons

Olivia Devereaux,

Matthew C. Herne, Nicolás E. Campione

et al.

Journal of Paleontology, Journal Year: 2025, Volume and Issue: unknown, P. 1 - 9

Published: March 19, 2025

Abstract Insights into the paleoneurology and endocranial anatomy of ornithopod dinosaurs come largely from Northern Hemisphere taxa. The recently described non-hadrosaurid iguanodontian Fostoria dhimbangunmal Cenomanian eastern Australia includes a partial skull that offers novel insights its (i.e., cavity housing brain). Here, we describe F . based on digital cranial endocast obtained computed tomography. is mostly complete; however, it diagenetically dorsoventrally compressed ventral limits are not preserved. generally consistent with other iguanodontians, including well-developed olfactory apparatus, suggesting good sense smell. In contrast to hadrosaurids some possesses ancestral flexure condition, in which pontine angles subequal. cerebrum makes up significant portion volume; cerebral hemispheres as enlarged or bulbous seen hadrosaurids. forebrain did fill braincase same extent A distinct vacuity supraoccipital may represent new autapomorphy. This study provides first neuroanatomy an Australian dinosaur.

Language: Английский

Citations

0
Ontogenetic Changes in Endocranial Anatomy in Gorgosaurus libratus (Theropoda: Tyrannosauridae) Provide Insight Into the Evolution of the Tyrannosauroid Endocranium DOI Creative Commons
Jared T. Voris, François Therrien,

Ryan C. Ridgely

et al.

The Journal of Comparative Neurology, Journal Year: 2025, Volume and Issue: 533(5)

Published: April 28, 2025

ABSTRACT Over the past two decades, increased accessibility to computed tomography (CT) scanners has greatly facilitated documentation of endocranium in numerous extinct theropod taxa. However, most these studies have focused on morphology mature individuals, thus changes or variation through ontogeny theropods remains largely unknown. The current study sheds light endocranial anatomy eutyrannosaurian tyrannosauroid, Gorgosaurus libratus , both an ontogenetic and evolutionary context. Based CT scans six braincases, including those recently discovered juvenile we virtually reconstruct describe for a growth series G. . Despite considerable skull architecture, relatively few occurred These include subtle increase length hindbrain region endocast inflation tympanic sinus diverticula adults relative juveniles. Among significant is decrease distinctiveness brain endocasts as mature. exhibit better defined cerebral hemispheres, optic lobes, cerebella than larger more individuals. This suggests closer correspondence between tyrannosaurids, indicating individuals provides accurate representation structure its regions displays mix basal archosaurian traits derived coelurosaurian traits. More primitive features large olfactory bulbs tracts, posteroventrally oriented long axis cerebrum, posteriorly positioned whereas prominent flexure, somewhat enlarged cerebellum that at least partially separates left right lobes. An understanding acquisition such leading avian may be further elucidated via (more reflective structure/organization various regions) earlier‐diverging (e.g., Allosauroidea, Megalosauroidea, Coelophysoidea).

Language: Английский

Citations

0
How smart was T. rex? Testing claims of exceptional cognition in dinosaurs and the application of neuron count estimates in palaeontological research DOI Creative Commons
Kai R. Caspar, Cristián Gutiérrez‐Ibáñez, Ornella Bertrand

et al.

The Anatomical Record, Journal Year: 2024, Volume and Issue: 307(12), P. 3685 - 3716

Published: April 26, 2024

Recent years have seen increasing scientific interest in whether neuron counts can act as correlates of diverse biological phenomena. Lately, Herculano-Houzel (2023) argued that fossil endocasts and comparative neurological data from extant sauropsids allow to reconstruct telencephalic Mesozoic dinosaurs pterosaurs, which might proxies for behaviors life history traits these animals. According this analysis, large theropods such Tyrannosaurus rex were long-lived, exceptionally intelligent animals equipped with "macaque- or baboon-like cognition", whereas sauropods most ornithischian would displayed significantly smaller brains an ectothermic physiology. Besides challenging established views on dinosaur biology, claims raise questions count estimates could benefit research general. Here, we address findings by revisiting Herculano-Houzel's work, identifying several crucial shortcomings regarding analysis interpretation. We present revised encephalization dinosaurs, derive phylogenetically informed modeling amended dataset endocranial measurements. For large-bodied particular, recover lower than previously proposed. Furthermore, review the suitability variables numbers relative brain size predict cognitive complexity, metabolic rate coming conclusion they are flawed Instead relying when reconstructing argue integrative studies needed approach complex subject.

Language: Английский

Citations

3
Neuroanatomy of the late Cretaceous Thescelosaurus neglectus (Neornithischia: Thescelosauridae) reveals novel ecological specialisations within Dinosauria DOI Creative Commons
David J. Button, Lindsay E. Zanno

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Nov. 6, 2023

Abstract Ornithischian dinosaurs exhibited a diversity of ecologies, locomotory modes, and social structures, making them an ideal clade in which to study the evolution neuroanatomy behaviour. Here, we present 3D digital reconstruction endocranial spaces latest Cretaceous neornithischian Thescelosaurus neglectus , order interpret paleobiology one last surviving non-avian dinosaurs. Results demonstrate that brain was relatively small compared most other neornithischians, instead suggesting cognitive capabilities within range extant reptiles. Other traits include narrow hearing range, with limited ability distinguish high frequencies, paired unusually well-developed olfactory lobes anterior semicircular canals, indicating acute olfaction vestibular sensitivity. This character combination, conjunction features postcranial anatomy, is consistent specializations for burrowing behaviours clade, as evidenced by trace skeletal fossil evidence earlier-diverging thescelosaurids, although whether they reflect ecological adaptations or phylogenetic inheritance T. itself unclear. Nonetheless, our results provide first neurological identified Ornithischia, more generally, expanding recognized this major clade.

Language: Английский

Citations

7
How smart wasT. rex? Testing claims of exceptional cognition in dinosaurs and the application of neuron count estimates in palaeontological research DOI Creative Commons
Kai R. Caspar, Cristián Gutiérrez‐Ibáñez, Ornella Bertrand

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 12, 2024

Recent years have seen increasing scientific interest in whether neuron counts can act as correlates of diverse biological phenomena. Lately, Herculano-Houzel (2023) argued that fossil endocasts and comparative neurological data from extant sauropsids allow to reconstruct telencephalic Mesozoic dinosaurs pterosaurs, which might proxies for behaviors life history traits these animals. According this analysis, large theropods such Tyrannosaurus rex were long-lived, exceptionally intelligent animals equipped with 'macaque- or baboon-like cognition' whereas sauropods well most ornithischian would displayed significantly smaller brains an ectothermic physiology. Besides challenging established views on dinosaur biology, claims raise questions count estimates could benefit research general. Here, we address findings by revisiting Herculano-Houzel's work, identifying several crucial shortcomings regarding analysis interpretation. We present revised encephalization dinosaurs, derive phylogenetically informed modeling amended dataset endocranial measurements. For large-bodied particular, recover lower than previously proposed. Furthermore, review the suitability variables numbers relative brain size predict cognitive complexity, metabolic rate coming conclusion they are flawed Instead relying when reconstructing argue integrative studies needed approach complex subject.

Language: Английский

Citations

2
A proxy for brain‐to‐endocranial cavity index in non‐neornithean dinosaurs and other extinct archosaurs DOI
Fabien Knoll,

Asato Ishikawa,

Soichiro Kawabe

et al.

The Journal of Comparative Neurology, Journal Year: 2024, Volume and Issue: 532(3)

Published: March 1, 2024

Abstract Although the brain fills nearly entire cranial cavity in birds, it can occupy a small portion of crocodilians. The lack data regarding volumetric correspondence between and hampers thorough assessments degree encephalization non‐neornithean dinosaurs other extinct archosaurs and, consequently, informed inferences their cognitive capacities. Existing suggest that, across extant archosaurs, endocranial doming volume intracranial nonneural components are inversely related. We build upon this information to develop an equation relating these two anatomical features archosaurs. rely on measurements endocast brain‐to‐endocranial (BEC) index relatives dinosaurs, namely, crurotarsans Caiman crocodilus , Crocodylus niloticus porosus ; paleognaths Struthio camelus Apteryx mantelli fowl Macrocephalon maleo Gallus gallus Meleagris gallopavo Phasianus colchicus Anas platyrhynchos . Applying representative endocasts from major clades we found that BEC varies about 0.6 ceratopsians thyreophorans around 0.7 ornithopods, pachycephalosaurians, sauropods, theropods. We, therefore, warn against use catch‐all value, like 0.5, instead encourage refinement adoption

Language: Английский

Citations

2
¿Qué nos dicen sus huellas? Muchas preguntas y algunas respuestas sobre la vida de los dinosaurios no avianos DOI Creative Commons
Ignacio Díaz‐Martínez, Paolo Citton, Diego Castanera

et al.

Journal of Iberian Geology, Journal Year: 2023, Volume and Issue: 50(1), P. 5 - 26

Published: Dec. 28, 2023

Abstract Dinosaur tracks are considerably common in the fossil record and were described from many areas world. They provide a live picture of dinosaur behaviour offer valuable data about different aspects trackmaker paleobiology. The ichnological allows gain information autopod anatomy, functional adaptations, stance gaits with which dinosaurs moved. This information, is often difficult to obtain body-fossil alone, making inferences not only concerning single individuals who produced footprints, but also within an evolutionary context. Footprints evidences abilities that had swim, run or certain pathologies. allowed inferring how they move herds even made courtship rituals. study enables reconstruction paleocommunities including predator–prey interaction. On other hand, footprints useful paleoenvironmental indicators, informing moisture content, bathymetry, paleocurrents, subaqueous substrates, zonations lacustrine margins, etc. In addition, it has been proposed track assemblages can be related facies (ichnofacies), order refine reconstructions. sometimes shadow respect skeletal record. However, obtained complements completes knowledge we have life dinosaurs, showing previously unknown aspects. work overview non-avian trying answer some questions their life.

Language: Английский

Citations

3
Neurocranial anatomy of Paralligator (Neosuchia: Paralligatoridae) from the Upper Cretaceous of Mongolia DOI
Ivan T. Kuzmin, Ekaterina A. Sichinava, E. V. Mazur

et al.

Zoological Journal of the Linnean Society, Journal Year: 2024, Volume and Issue: 203(1)

Published: Dec. 13, 2024

Abstract Neurocranial features appear to be phylogenetically informative and key in assessing the still contentious relationships within Crocodylomorpha. However, braincases of many non-crocodylian taxa are incompletely studied precluding assessment evolutionary modifications at base Crocodylia. Here, we describe braincase osteology neuroanatomy paralligatorid crocodylomorph Paralligator from Upper Cretaceous Mongolia based on computed tomography (CT)-scanning, segmentation, 3D modelling several specimens. The anatomy brain endocast, nerves, paratympanic pneumatic cavities is consistent with its phylogenetic position close or Eusuchia. shares a suit neuroanatomical basal eusuchians crocodylians reflecting plesiomorphic condition for In addition, differences endocasts between larger-sized individuals Kansajsuchus smaller Shamosuchus ontogenetic changes extant crocodylians. This suggests that members more clade Paralligatoridae crown-group Crocodylia share similar during ontogeny. We also review distribution mesethmoid Crocodylomorpha show presence clades including Dyrosauridae.

Language: Английский

Citations

0
Convergent avialan brain morphology in Sinovenator (Troodontidae, Theropoda) DOI Creative Commons
Congyu Yu, Akinobu Watanabe, Zichuan Qin

et al.

Research Square (Research Square), Journal Year: 2023, Volume and Issue: unknown

Published: Jan. 19, 2023

Abstract Multiple modifications to the skull and brain anatomy occurred along lineage encompassing bird-line theropod dinosaurs modern birds. Anatomical changes endocranium include an enlarged endocranial cavity, relatively larger optic lobe that implies elevated visual acuity, proportionately smaller olfactory bulbs suggests reduced olfaction. Here, we use micro-computed tomographic (CT) imaging reconstruct its structures from exceptionally well-preserved of Sinovenator changii (Troodontidae, Theropoda). While overall morphology resembles typical other troodontids, also exhibits unique features are similar paravian taxa non-maniraptoran theropods. Landmark-based geometric morphometric analysis on shape non-avialan avian points most closely resembling Archaeopteryx , thus indicating convergent evolution avialan in troodontids wide existence such architecture Maniraptora. Institutional abbreviations : IVPP Institute Vertebrate Paleontology Paleoanthropology, Chinese Academy Sciences, Beijing 100044, China. PMOL Paleontological Museum Liaoning, Shenyang 110034,

Language: Английский

Citations

0