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Full-Text Articles in Animal Studies
Neuroanatomy Of The Subadult And Fetal Brain Of The Atlantic White-Sided Dolphin (Lagenorhynchus Acutus) From In Situ Magnetic Resonance Images, Eric W. Montie, Gerald E. Schneider, Darlene R. Ketten, Lori Marino, Katie E. Touhey, Mark E. Hahn
Neuroanatomy Of The Subadult And Fetal Brain Of The Atlantic White-Sided Dolphin (Lagenorhynchus Acutus) From In Situ Magnetic Resonance Images, Eric W. Montie, Gerald E. Schneider, Darlene R. Ketten, Lori Marino, Katie E. Touhey, Mark E. Hahn
Veterinary Science and Medicine Collection
This article provides the first anatomically labeled, magnetic resonance imaging (MRI) -based atlas of the subadult and fetal Atlantic white-sided dolphin (Lagenorhynchus acutus) brain. It differs from previous MRI-based atlases of cetaceans in that it was created from images of fresh, postmortem brains in situ rather than extracted, formalin-fixed brains. The in situ images displayed the classic hallmarks of odontocete brains: fore-shortened orbital lobes and pronounced temporal width. Olfactory structures were absent and auditory regions (e.g., temporal lobes and inferior colliculi) were enlarged. In the subadult and fetal postmortem MRI scans, the hippocampus was identifiable, despite the relatively small size …
Cetacean Brains: How Aquatic Are They?, Lori Marino
Cetacean Brains: How Aquatic Are They?, Lori Marino
Anatomy Collection
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 relationship exists between being fully aquatic and having a large brain is addressed. It has been hypothesized that the large, well‐developed cetacean brain is a direct product of adaptation to …
Does Diving Limit Brain Size In Cetaceans?, Lori Marino, Daniel Sol, Kristen Toren, Louis Lefebvre
Does Diving Limit Brain Size In Cetaceans?, Lori Marino, Daniel Sol, Kristen Toren, Louis Lefebvre
Veterinary Science and Medicine Collection
We test the longstanding hypothesis, known as the dive constraint hypothesis, that the oxygenation demands of diving pose a constraint on aquatic mammal brain size.Using a sample of 23 cetacean species we examine the relationship among six different measures of relative brain size, body size, and maximum diving duration. Unlike previous tests we include body size as a covariate and perform independent contrast analyses to control for phylogeny. We show that diving does not limit brain size in cetaceans and therefore provide no support for the dive constraint hypothesis. Instead, body size is the main predictor of maximum diving duration …
Neuroanatomy Of The Killer Whale (Orcinus Orca) From Magnetic Resonance Images, Lori Marino, Chet C. Sherwood, Bradley N. Delman, Cheuk Y. Tang, Thomas P. Naidisch, Patrick R. Hof
Neuroanatomy Of The Killer Whale (Orcinus Orca) From Magnetic Resonance Images, Lori Marino, Chet C. Sherwood, Bradley N. Delman, Cheuk Y. Tang, Thomas P. Naidisch, Patrick R. Hof
Veterinary Science and Medicine Collection
This article presents the first series of MRI-based anatomically labeled sectioned images of the brain of the killer whale (Orcinus orca). Magnetic resonance images of the brain of an adult killer whale were acquired in the coronal and axial planes. The gross morphology of the killer whale brain is comparable in some respects to that of other odontocete brains, including the unusual spatial arrangement of midbrain structures. There are also intriguing differences. Cerebral hemispheres appear extremely convoluted and, in contrast to smaller cetacean species, the killer whale brain possesses an exceptional degree of cortical elaboration in the insular cortex, temporal …
Anatomy And Three-Dimensional Reconstructions Of The Brain Of The White Whale (Delphinapterus Leucas) From Magnetic Resonance Images, Lori Marino, Timothy L. Murphy, Amy L. Deweerd, John A. Morris, Archibald J. Fobbs, Nathalie Humbolt, Sam H. Ridgway, John I. Johnson
Anatomy And Three-Dimensional Reconstructions Of The Brain Of The White Whale (Delphinapterus Leucas) From Magnetic Resonance Images, Lori Marino, Timothy L. Murphy, Amy L. Deweerd, John A. Morris, Archibald J. Fobbs, Nathalie Humbolt, Sam H. Ridgway, John I. Johnson
Veterinary Science and Medicine Collection
Magnetic resonance imaging offers a means of observing the internal structure of the brain where traditional procedures of embedding, sectioning, staining, mounting, and microscopic examination of thousands of sections are not practical. Furthermore, internal structures can be analyzed in their precise quantitative spatial interrelationships, which is difficult to accomplish after the spatial distortions often accompanying histological processing. For these reasons, magnetic resonance imaging makes specimens that were traditionally difficult to analyze, more accessible. In the present study, images of the brain of a white whale (Beluga) Delphinapterus leucas were scanned in the coronal plane at 119 antero-posterior levels. Fromthese scans, …