Cetacean brains: How aquatic are they?

@article{Marino2007CetaceanBH,
  title={Cetacean brains: How aquatic are they?},
  author={Lori Marino},
  journal={The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology},
  year={2007},
  volume={290}
}
  • L. Marino
  • Published 1 June 2007
  • Medicine, Biology
  • The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
The adaptation of cetaceans to a fully aquatic lifestyle represents one of the most dramatic transformations in mammalian evolutionary history. Two of the most salient features of modern cetaceans are their fully aquatic lifestyle and their large brains. This review article will offer an overview of comparative neuroanatomical research on aquatic mammals, including analyses of odontocete cetacean, sirenian, pinniped, and fossil archaeocete brains. In particular, the question of whether a… Expand
View on Wiley
animalstudiesrepository.org
50 Citations
Highly Influential Citations
4
Background Citations
23
Methods Citations
1
Results Citations
1

50 Citations

Citation Type

Citation Type

The neocortex of cetaceans: cytoarchitecture and comparison with other aquatic and terrestrial species
The evolutionary process of readaptation to the aquatic environment was accompanied by extreme anatomical and physiological changes in the brain. This review discusses cortical specializations in the… Expand
Co‐evolution of cerebral and cerebellar expansion in cetaceans
TLDR
The results suggest that major increases in both cerebrum and cerebellum size occurred early in cetacean evolution, prior to the origin of the major extant clades, and predate the evolution of echolocation. Expand
THE EVOLUTIONARY HISTORY OF CETACEAN BRAIN AND BODY SIZE
TLDR
It is suggested that cetacean brain and body mass evolved under strong directional trends to increase through time, but decreases in EQ were widespread, and that until recently the most encephalized mammals were odontocetes, not primates. Expand
The size and complexity of dolphin brains—a paradox?
  • S. Huggenberger
  • Biology
  • Journal of the Marine Biological Association of the United Kingdom
  • 2008
TLDR
It is suggested that the evolution of the large dolphin brain was possible due to a combination of different prerequisites based on adaptations to the aquatic environment including the sonar system and the rudimentary pelvic girdle did not limit brain size at birth. Expand
The Cerebral Cortex of the Pygmy Hippopotamus, Hexaprotodon liberiensis (Cetartiodactyla, Hippopotamidae): MRI, Cytoarchitecture, and Neuronal Morphology
TLDR
The present study provides a comprehensive dataset of the neuroanatomy of H. liberiensis that sets the ground for future comparative studies including the larger Hippopotamus amphibius. Expand
The pattern of brain-size change in the early evolution of cetaceans
TLDR
The data show that brain size increased at the origin of basilosaurids, 5 million years before the Eocene-Oligocene transition, and it is suggested that cetacean relative brain size is most accurately portrayed using EQs based on the scaling coefficients as observed in the closely related terrestrial artiodactyls. Expand
Positive selection at the ASPM gene coincides with brain size enlargements in cetaceans
TLDR
It is of particular interest to find that positive selection was restricted to cetaceans and primates, two distant lineages both characterized by a massive expansion of brain size. Expand
Anatomical adaptations of aquatic mammals
TLDR
The articles in this issue are a blend of literature review and new, hypothesis‐driven anatomical research, which highlight the special nature of anatomical form and function in aquatic mammals that enables their exquisite adaptation for life in such a challenging environment. Expand
The Evolution of Brains and Cognitive Abilities
Humans place great significance in intellectual abilities, and because of this, biologists have been interested in the cognitive abilities of animals since Aristotle. The difficulties in defining… Expand
Comparative anatomical description of brain hemisphere surfaces in toninha dolphin and humans
TLDR
The telencephalon of Pontoporia blainvillei is rostrally tapered and expanded at the caudal end and it has a greater number of folds/gyrus when compared to human species, as the presence of the an efficient auditive system in dolphins is associated with specific function of the species. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 42 REFERENCES
Cortical complexity in cetacean brains.
  • P. Hof, R. Chanis, L. Marino
  • Medicine, Biology
  • The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology
  • 2005
TLDR
Data on brain size and hemisphere surface configuration in several cetacean species are summarized and an overview of the cytoarchitectural complexity of the cerebral cortex of the bottlenose dolphin is presented. Expand
Origin and evolution of large brains in toothed whales.
  • L. Marino, D. McShea, M. Uhen
  • Biology, Medicine
  • The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology
  • 2004
TLDR
It is shown that brain size increased significantly in two critical phases in the evolution of odontocetes, and was accompanied by a decrease in body size in Delphinoidea only by 15 million years ago. Expand
Brain Size Evolution
TLDR
This chapter explores the brain size evolution of marine mammals with a focus on encephalization Quotient, a measure of observed brain size relative to expected brain size derived from a regression of brain weight on body weight for a sample of species. Expand
Evolution of marine mammals: Back to the sea after 300 million years
  • M. Uhen
  • Biology, Medicine
  • Anatomical record
  • 2007
TLDR
The earliest representatives of these clades all show morphological features that indicate they were feeding while in the water, suggesting that feeding ecology is a key factor in the evolution of marine mammals. Expand
Skeletons of terrestrial cetaceans and the relationship of whales to artiodactyls
TLDR
Cladistic analysis of the skeletons of two early Eocene pakicetid cetaceans, the fox-sized Ichthyolestes pinfoldi, and the wolf-sized Pakicetus attocki, indicates that cetACEans are more closely related to artiodactyls than to any mesonychian, and supports monophyly of artiodACTyls. Expand
A Comparison of Encephalization between Odontocete Cetaceans and Anthropoid Primates
  • L. Marino
  • Medicine, Biology
  • Brain, Behavior and Evolution
  • 1998
TLDR
Results show that the encephalization level of Homo sapiens is still extraordinary relative to that of nonhuman species, but a subset of delphinid odontocetes are significantly more highly encephalized than the most highlyEncephalized anthropoid primates and narrow the gap in encephalizations between humans and nonhumans substantially. Expand
The anatomy of the brain of the bottlenose dolphin (Tursiops truncatus). Surface configurations of the telencephalon of the bottlenose dolphin with comparative anatomical observations in four other cetacean species
TLDR
The surface demarcation of the rhinencephalon and the cleavage of each hemisphere into concentric tiers are sharper and clearer in the cetacean brain than in any other mammalian brain. Expand
Morphogenesis of the brain in the harbour porpoise
TLDR
Investigation of reconstructions from serial sections of successive prenatal stages of the harbour porpoise revealed that a common ontogenetic plan regarding the chronological sequence of morphogenetic events exists in mammalian orders as different as primates and odontocetes. Expand
The Auditory Central Nervous System of Dolphins
TLDR
Although there have been no specific studies on hearing by the cetacean fetus, clearly other mammals have demonstrated a capability to hear in the womb well before birth. Expand
Magnetic resonance images of the brain of a dwarf sperm whale (Kogia simus)
TLDR
This paper represents the first MRI‐based anatomically labelled three‐dimensional description of the dwarf sperm whale brain and displays the proportions and positions of major neuroanatomical features. Expand
...
1
2
3
4
5
...