Paleoneurology of Amniotes: New Directions in the Study of Fossil Endocasts

List of Reviewers
Contents
About the Editors
Contributors
Chapter 1: Introduction
References
Chapter 2: The Paleoneurology of Early Reptiles
2.1 Early Evolutionary History and Diversity of Reptiles
2.2 Historical Background
2.2.1 The Fossil Record
2.2.2 Unresolved Issues
2.3 Anatomical Overview
2.3.1 Characterization of Cranial Endocast Morphology
2.3.2 Spaces Associated with Cranial Blood Supply
2.4 Brain Evolution and Paleobiological Inferences
2.4.1 Morphological Brain Diversity
2.4.2 Brain-Size Evolution and Encephalization Quotient
2.4.3 Sensory Perception
Hearing and Balance
Olfaction
2.5 Outstanding Questions and Perspectives
2.6 Conclusions
References
Chapter 3: The Paleoneurology of Ichthyopterygia and Sauropterygia: Diverse Endocranial Anatomies of Secondarily Aquatic Diapsids
3.1 Systematics and Phylogenetic Context
3.1.1 Ichthyopterygia Owen, 1860
3.1.2 Sauropterygia Owen, 1860
3.2 Historical Background
3.2.1 The Record of Endocranial Morphologies and Other Paleoneurological Features in Ichthyopterygia and Sauropterygia
3.2.2 Problematics
3.3 Overview of General and Comparative Anatomy
3.3.1 Characterization of Cranial Endocast Morphology
Ichthyopterygia
Sauropterygia
3.3.2 Voids Associated with Cranial Blood Supply
Ichthyopterygia
Sauropterygia
3.4 Brain Evolution and Paleobiologic Inferences Based on Endocast Morphology
3.4.1 Morphological Brain Diversity
Ichthyopterygia
Sauropterygia
3.4.2 Brain-Size Evolution and Encephalization Quotient
3.4.3 Sensory Evolution in Ichthyopterygia and Sauropterygia
Ichthyopterygia
Sauropterygia
3.5 Future Directions: Outstanding Questions and Perspectives
3.6 Conclusions
References
Chapter 4: Contrasting Brains and Bones: Neuroanatomical Evolution of Turtles (Testudinata)
4.1 Systematic and Phylogenetic Context
4.2 Historical Background
4.2.1 Summary of Neuroanatomical Research History
4.2.2 Problematics
4.3 Overview of General and Comparative Anatomy
4.3.1 Characterization of Neuroanatomical Structures
Brain Morphology of Turtles
Cranial Nerves of Turtles
Braincase Endocast Morphology of Turtles and Correspondence of Brain and Endocast Shape
Ontogeny of the Turtle Brain and Endocast
Variation in Adult Braincase Endocast Morphology
4.3.2 Spaces Associated with Cranial Blood Supply
Evolution of the Blood Canal System in Turtles
Digital Dissection of Major Cranial Blood Vessels in Trachemys scripta
4.4 Brain Evolution and Paleobiologic Inferences Based on Endocast Morphology
4.4.1 Brain-Size Evolution
4.4.2 Sensory Evolution
Vestibular Sense
Hearing
Vision
Olfaction
4.5 Future Directions
4.6 Concluding Remarks
References
Chapter 5: A Look in to the Neurocranium of Living and Extinct Lepidosauria
5.1 Introduction
5.1.1 The Osseous Braincase
5.1.2 The Brain and Cranial Nerves
5.2 Phylogeny and Diversity of Lepidosauria
5.2.1 Early Diverging Lepidosaurian Lineages
5.2.2 Rhynchocephalia Günter, 1867
5.2.3 Squamata Oppel, 1811
The Extinct Mosasauria
5.3 Lepidosaur Braincase Diversity and the Fossil Record
5.3.1 Braincase of Stem-Lepidosaurians
5.3.2 Braincase of Rhynchocephalia
Endocranial Features of Stem-Rhynchocephalia
5.3.3 Squamata
Braincase of Stem-Squamata
Braincase of Dibamidae
Braincase of Gekkonomorpha
Braincase of Scinciformata
Braincase of Laterata
Braincase of Toxicofera
Braincase of Extinct Snakes and Available Endocranial Features
5.4 Overview of General Comparative Neuroanatomy
5.4.1 Characterization of the Reptilian Central Nervous System
5.4.2 Brain Morphology of Sphenodon
5.4.3 Brain Morphology of the Squamata
Brain Morphology of Lizards
Endocranial Casts in Lizards
Brain Morphology of Snakes
5.5 Paleoneurology
5.5.1 Sources of Data for Paleoneurology and Limitation for the Study
5.5.2 Paleoneurology of Snakes and Mosasauroids: Cranial Endocasts and Other Sources of Information
Paleoneuroanatomy of Dinilysia patagonica
Paleoneuroanatomy of Mosasauroidea
Inner Ear of Extant and Extinct Lepidosaurians
5.6 Future Directions and Conclusions
5.7 Conclusions
References
Chapter 6: Paleoneurology of the Early Diversification of Triassic Archosauriforms and Pseudosuchians
6.1 Systematic and Phylogenetic Context
6.2 Historical Background
6.2.1 Problematics
6.3 Overview of General and Comparative Anatomy
6.3.1 Non-archosaurian Archosauriforms
Proterosuchidae
Erythrosuchidae
Protopyknosia
Euparkeriidae
Vanclavea and Litorosuchus
Doswelliidae
Proterochampsidae
6.3.2 Pseudosuchian Archosaurs
Phytosauria
Aetosauria
Ornithosuchidae
Erpetosuchidae
Gracilisuchidae
Poposauroidea
Non-crocodylomorph Loricata
6.4 Brain Evolution and Paleobiological Inferences
6.4.1 Sensory Evolution
6.5 Future Directions
6.6 Concluding Remarks
References
Chapter 7: An Overview on the Crocodylomorpha Cranial Neuroanatomy: Variability, Morphological Patterns and Paleobiological Implications
7.1 Phylogenetic Context and Introduction to Paleoneurology of Crocodylomorpha
7.2 Overview of General and Comparative Anatomy
7.2.1 Neuroanatomy of Extant Crocodylians
Brain
Inner Ear
Cranial Nerves of Crocodylomorphs
7.2.2 Comparative Anatomy of Crocodylomorph Brain and Inner Ear
Non-crocodyliform Crocodylomorphs and Basal Crocodyliforms
Thalattosuchia (Teleosauroidea and Metriorhynchoidea)
Notosuchia (Uruguaysuchidae, Peirosauridae and Sebecosuchia)
Early Eusuchians and Crocodylia
7.2.3 Cranial Nerves of Crocodylomorphs
7.3 Paleobiological Implications of Crocodyliform Neuroanatomy
7.4 Final Remarks
References
Chapter 8: Paleoneurology of Non-avian Dinosaurs: An Overview
8.1 Phylogenetic Context
8.1.1 Saurischia Seeley 1887
Theropoda Marsh 1881
Sauropodomorpha von Huene 1932
8.1.2 Ornithischia Seeley 1888
Thyreophora Nopcsa 1915
Neornithischia Cooper 1985
8.2 Historical Background
8.2.1 Brief Summary of the History of Dinosaur Paleoneurology
Brains vs. Spinal Cord
Early Studies and Current State of Knowledge of Dinosaur Paleoneurology
8.2.2 Non-invasive Techniques and Paleoneurology
8.2.3 Problems for the Study of Dinosaur ‘Brains’
8.2.4 Cranial Endocast Reliability
8.2.5 Brain to Endocranial Cavity Ratio
8.2.6 Ontogeny
8.3 Overview of General and Comparative Brain Anatomy
8.3.1 The Reptilian Central Nervous System
8.3.2 Characterization of Cranial Endocast Morphology in Dinosaurs
Generalized Dinosaur Endocast
The Cranial Endocast of Theropoda
The Endocast of Sauropodomorpha
The Cranial Endocast of Ornithischia
8.4 Evolutionary Patterns in Dinosaur Neuroanatomy
8.4.1 Encephalization Quotient
8.4.2 Brain Architecture and Evolution
8.5 Future Directions and Conclusions
References
Chapter 9: Anatomy and Evolution of Avian Brain and Senses: What Endocasts Can Tell Us
9.1 Systematic and Phylogenetic Context
9.2 Historical Background
9.3 The Bauplan of the Avian Brain
9.4 Avian Brain Disparity
9.5 Cranial Nerves
9.6 Brain Vascularization
9.7 Brain Size
9.8 Senses
9.8.1 Inner Ear
9.8.2 Vision
9.8.3 Olfaction
9.9 The Non-avian Theropod – Aves Brain and Senses Transition
9.10 Concluding Remarks
References
Chapter 10: Evolution of the Mammalian Neurosensory System: Fossil Evidence and Major Events
10.1 Phylogenetic Context
10.2 Historical Background
10.3 The Ancestral Amniote
10.3.1 The Amniote Skeleton
10.3.2 Peripheral Sensory System
Olfactory system
Visual System
Auditory System
Peripheral Somatosensory System
The Ancestral Amniote Brain
10.4 Early Pan-Mammalian History
10.4.1 Node 4: Therapsida
10.4.2 Node 9: Cynodontia
10.4.3 Node 11 (Unnamed)
10.4.4 Node 12: Probainognathia
10.4.5 Node 14: Mammaliamorpha
10.4.6 Node 15: Mammaliaformes
10.4.7 Node 16: Unnamed
10.4.8 Node 17: Mammalia
Ossified Ethmoid Complex
The Mammalian Middle Ear
Orofacial Motor Skills
Spinal Cord
Nocturnality
10.5 Discussion
References
Chapter 11: Evolution of the Brain and Sensory Structures in Metatherians
11.1 Marsupial Origins, Diversity, and Phylogenetic Relationships
11.1.1 Marsupial Biogeography
11.1.2 Marsupial Diversity
11.1.3 Are Marsupials Representative of a Small-Brained, Primitive Mammalian Ancestor?
11.2 Historical Background
11.2.1 The Record of Endocranial Morphology and any Other Paleoneurological Approaches in the Group Under Study
11.2.2 Problematics
11.3 Overview of General and Comparative Anatomy
11.3.1 Endocast Morphology
11.3.2 Spaces Associated with Cranial Blood Supply
11.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
11.4.1 Morphological Brain Diversity
Endocasts and Phylogenetic Traits
Functional and/or Behavioral Interpretations of Endocast Morphology
11.4.2 Brain-Size Evolution and Encephalization Quotient
Marsupial Brain Size and Behavioral Correlates
11.4.3 Sensory Evolution: Vision, Somatosensory System, Auditory System, Vestibular Sense, Olfaction
11.4.4 Brain Anatomy in Marsupials Versus Placentals
11.5 Future Directions: Outstanding Questions and Perspectives
11.6 Concluding Remarks
References
Chapter 12: Early Evolution of the Brain in Primates and Their Close Kin
12.1 Systematic and Phylogenetic Context
12.1.1 The Phylogenetic Position of Primates Within Mammalia
12.1.2 Taxonomy and Phylogeny of Primates
12.2 Historical Background
12.2.1 The Record of Endocranial Morphology and Any Other Paleoneurological Approaches in the Group Under Study
Pre-CT
Post-CT
12.2.2 Problematics
12.3 Overview of General and Comparative Anatomy
12.3.1 Characterization of Cranial Endocast Morphology
Plesiadapiformes
Adapoids and Omomyoids
12.3.2 Spaces Associated with Cranial Blood Supply
12.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
12.4.1 Morphological Brain Diversity
12.4.2 Brain-Size Evolution and Encephalization Quotient
12.4.3 Sensory Evolution: Vestibular Sense, Vision, Hearing, Olfaction, Taste, etc.
12.4.4 Evolution, Form and Function of Derived Brain Structures
12.5 Future Directions: Outstanding Questions and Perspectives
12.6 Concluding Remarks/Final Considerations
References
Chapter 13: Paleoneurology of Artiodactyla, an Overview of the Evolution of the Artiodactyl Brain
13.1 Systematic and Phylogenetic Context
13.2 Historical Background
13.2.1 Documentation of Artiodactyl Endocasts in the Fossil Record
Endocranial Morphology of Extinct Artiodactyla Clades
Endocasts of Modern Artiodactyl Groups
13.2.2 Problematics
13.3 Overview of General and Comparative Anatomy
13.3.1 Characterization of Cranial Endocast Morphology
Overview of Modern Artiodactyl Brain Morphology, Primary Identification of Structures
Endocranial Morphology of Extinct Artiodactyla Clades
Endocranial Morphology of Crown Artiodactyla Clades
13.3.2 Space Associated with Cranial Blood Vessels
13.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
13.4.1 Morphological Brain Diversity: General Picture of Brain Evolution in Artiodactyla
Olfactory Bulbs
Neopallium Size and Complexity
13.4.2 Brain-Size Evolution and Encephalization Quotient
Brain Size in Artiodactyla
Brain Size in Non-cetacean Artiodactyls
Brain Size in Cetacea
13.5 Future Directions: Outstanding Questions and Perspectives
13.6 Concluding Remarks
References
Chapter 14: Evolution of the Brain and Sensory Structures in Sirenia
14.1 Sirenian Biogeography, Fossil Record, and Phylogenetic Context
14.2 Historical Background
14.2.1 The Record of Endocranial Morphology and Any Other Paleoneurological Approaches to Sirenia
14.2.2 Problematics
14.3 Overview of General and Comparative Anatomy
14.3.1 Cranial Endocast Morphology
14.3.2 Spaces Associated with Cranial Blood Supply
14.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
14.4.1 Morphological Brain Diversity
14.4.2 Brain-Size Evolution and Encephalization Quotient
14.4.3 Sensory Evolution: Vision, Vestibular Sense, Hearing, Mechanoreception, Olfaction
14.4.4 Evolution and Form of Sirenian Brain Compared to Close Mammalian Relatives
14.5 Future Directions: Outstanding Questions and Perspectives
14.6 Concluding Remarks
References
Chapter 15: Paleoneurology of the Proboscidea (Mammalia, Afrotheria): Insights from Their Brain Endocast and Labyrinth
15.1 Historical Review and Current Data on the Variations of the Endocranial Cast Across Proboscidean Phylogeny
15.1.1 Introduction
15.2 Evolution of Endocranial Capacity
15.2.1 The Tools to Study the Evolution of Brain Size in Extinct Proboscideans
15.2.2 Patterns of Encephalization Evolution in Proboscideans
15.2.3 The Effect of Insular Dwarfism on Brain Size
15.2.4 Why Did Elephantimorpha Evolve an Enlarged Brain?
15.3 Evolution of Brain Morphology
15.3.1 Neuroanatomy of Modern Elephants
15.3.2 Morphology of the Endocranial Cast in Stem Proboscideans
15.3.3 Morphology of the Endocranial Cast in Elephantiformes
Evolution of the Temporal Lobe
Frontal Lobes and Olfactory Bulbs
The Cerebellum and Evolution of the Trunk
Cortical Sulcation and Gyrification
15.4 Evolution of the Bony Labyrinth, Hearing, and Balance
15.4.1 Historical Review
15.4.2 Bony Labyrinth Anatomy of Extant Elephants
15.4.3 Evolution of the Ear Region and Bony Labyrinth in Proboscidea
Basal Proboscideans
The Evolution of Low-Frequency Hearing
Deinotheriidae and Elephantimorpha
15.5 Final Considerations
References
Chapter 16: Brain Evolution in Fossil Rodents: A Starting Point
16.1 Systematic and Phylogenetic Context
16.2 Historical Background
16.2.1 The Record of Endocranial Morphology and Any Other Paleoneurological Approaches in the Group Under Study
16.2.2 Problematics
16.3 Overview of General and Comparative Anatomy
16.3.1 Characterization of Cranial Endocast Morphology
Ischyromyidae
Sciuroidea
Caviomorpha
16.3.2 Spaces Associated with Cranial Nerves and Blood Supply
16.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
16.4.1 Morphological Brain Diversity
16.4.2 Brain-Size Evolution and Encephalization Quotient
16.4.3 Sensory Evolution: Vestibular Sense, Vision, Hearing, Olfaction, Taste, etc.
16.5 Future Directions: Outstanding Questions and Perspectives
16.6 Concluding Remarks
Appendix
References
Chapter 17: Paleoneurology of Carnivora
17.1 Systematic and Phylogenetic Context
17.2 Historical Background
17.3 Overview of General and Comparative Anatomy
17.3.1 Characterization of Cranial Endocast Morphology of Living Taxa
17.3.2 Sensory Evolution
17.3.3 Cellular Composition
17.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
17.4.1 Morphological Brain Diversity Through Time
Eocene Carnivorans
Oligocene Carnivorans
Early and Middle Miocene Carnivorans
Late Miocene and Plio-Pleistocene Carnivorans
17.4.2 The Evolution of Gyrification in Carnivorans
17.4.3 Brain-Size Evolution
17.5 Concluding Remarks
References
Chapter 18: Paleoneurology of Extinct Cingulates and Insights into Their Inner Ear Anatomy
18.1 Systematic and Phylogenetic Context
18.2 Historical Background
18.2.1 The Record of Endocranial Morphology of Fossil Cingulates
18.2.2 Problematics
18.3 Overview of General and Comparative Anatomy
18.3.1 Characterization of Cranial Endocast Morphology
Armadillos
Glyptodonts
Pampatheres
18.3.2 Inner Ear Endocast Anatomy
18.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
18.4.1 Morphological Brain Diversity
18.4.2 Brain-Size Evolution and Encephalization Quotient
18.4.3 Sensory Evolution: Vestibular Sense
18.5 Future Directions: Outstanding Questions and Perspectives
18.6 Final Considerations
References
Chapter 19: The Endocranial Cavities of Sloths (Xenarthra, Folivora): Insights from the Brain Endocast, Bony Labyrinth, and Cranial Sinuses
19.1 Systematic and Phylogenetic Context
19.2 Historical Background
19.2.1 The Record of Endocranial Morphology of Fossil Sloths
19.3 Overview of General and Comparative Anatomy
19.3.1 Brain Cavity and Cranial Nerves
Brain Cavity
Cranial Nerves
19.3.2 Bony Labyrinth
19.3.3 Cranial Sinuses
19.4 Evolutionary Inferences Based on Endocast Morphology
19.4.1 Brain Cavity and Cranial Nerves
Brain Cavity
Cranial Nerves
19.4.2 Bony Labyrinth
19.4.3 Cranial Sinuses
19.5 Open Problems and Future Directions: Outstanding Questions and Perspectives
19.6 Concluding Remarks
References
Chapter 20: Endocranial Morphology and Paleoneurology in Notoungulates: Braincast, Auditory Region and Adjacent Intracranial Spaces
20.1 Systematic and Phylogenetic Context
20.1.1 South American Native Ungulates
20.1.2 Notoungulata
20.2 The Study of Notoungulates Braincast and Auditory Region over the Years
20.2.1 Braincast
20.2.2 Auditory Region
20.2.3 Advances in Recent Years
20.3 Overview of the Endocranial Morphology
20.3.1 Characterization of Notoungulate Braincast
20.3.2 Spaces Associated with Intracranial Blood Supply
20.3.3 Spaces Associated with the Middle and Inner Ear
20.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
20.4.1 Morphological Brain Diversity
20.4.2 Relative Brain Size Evolution: A Challenging Task in Notoungulates
20.4.3 Inferred Sensory and Locomotor Capabilities: Olfaction, Hearing and Vestibular Sense
20.5 Final Considerations: Conclusions, Outstanding Questions and Perspectives
References
Chapter 21: Paleoneurology of Litopterna: Digital and Natural Endocranial Casts of Macraucheniidae
21.1 Systematic and Phylogenetic Context
21.2 Historical Background
21.2.1 The Record of Endocranial Morphology and Any Other Paleoneurological Approaches in Litopterna
21.2.2 Problematics
21.3 Overview of General and Comparative Anatomy
21.3.1 Characterization of Endocranial Cast Morphology
CT Scanning and Endocast Acquisition
Criteria for Neuromorphological Interpretation
Description of the Digital Endocranial Casts and Neuromorphological Interpretation (Figs. 21.1, 21.2, 21.3 and 21.4)
Endocranial Spaces Associated with Pneumatization of the Cranial Roof
21.3.2 Natural Endocranial Cast (or Natural Brain Endocast)
21.4 Brain Evolution and Paleobiological Inferences Based on Endocast Morphology
21.4.1 Morphological Endocranial Cast Diversity
Comparative Neuromorphology with Extinct South American Native Ungulates and Living and Extinct Euungulata
Frontal Sinuses
21.4.2 Brain-Size Evolution and Encephalization Quotient
21.5 Future Directions: Oustanding Questions and Perspectives
21.6 Conclusions
References
Index