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Full-Text Articles in Animal Structures

Variation In Brain Morphology Of Intertidal Gobies: A Comparison Of Methodologies Used To Quantitatively Assess Brain Volumes In Fish, Gemma E. White, Culum Brown Aug 2015

Variation In Brain Morphology Of Intertidal Gobies: A Comparison Of Methodologies Used To Quantitatively Assess Brain Volumes In Fish, Gemma E. White, Culum Brown

Veterinary Science and Medicine Collection

When correlating brain size and structure with behavioural and environmental characteristics, a range of techniques can be utilised. This study used gobiid fishes to quantitatively compare brain volumes obtained via three different methods; these included the commonly used techniques of histology and approximating brain volume to an idealised ellipsoid, and the recently established technique of X-ray micro-computed tomography (micro-CT). It was found that all three methods differed significantly from one another in their volume estimates for most brain lobes. The ellipsoid method was prone to over- or under-estimation of lobe size, histology caused shrinkage in the telencephalon, and although micro-CT …


Diffusion Tensor Imaging Of Dolphin Brains Reveals Direct Auditory Pathway To Temporal Lobe, Gregory S. Berns, Peter F. Cook, Sean Foxley, Saad Jbabdi, Karla L. Miller, Lori Marino Jul 2015

Diffusion Tensor Imaging Of Dolphin Brains Reveals Direct Auditory Pathway To Temporal Lobe, Gregory S. Berns, Peter F. Cook, Sean Foxley, Saad Jbabdi, Karla L. Miller, Lori Marino

Veterinary Science and Medicine Collection

The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes’ auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this position induced by expansion of ‘associative0 regions in lateral and caudal directions. However, the precise location of the auditory cortex and its connections are still unknown. Here, …


Microhabitat Use Affects Brain Size And Structure In Intertidal Gobies, Gemma E. White, Culum Brown May 2015

Microhabitat Use Affects Brain Size And Structure In Intertidal Gobies, Gemma E. White, Culum Brown

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The ecological cognition hypothesis poses that the brains and behaviours of individuals are largely shaped by the environments in which they live and the associated challenges they must overcome during their lives. Here we examine the effect of environmental complexity on relative brain size in 4 species of intertidal gobies from differing habitats. Two species were rock pool specialists that lived on spatially complex rocky shores, while the remainder lived on dynamic, but structurally simple, sandy shores. We found that rock pool-dwelling species had relatively larger brains and telencephalons in particular, while sand-dwelling species had a larger optic tectum and …


Acoustic Divergence In The Rut Vocalizations Of Persian And European Fallow Deer, J. B. Stachowicz, E. Vannoni, B. J. Pitcher, Elodie F. Briefer, E. Geffen, A. G. Mcelligott Jan 2014

Acoustic Divergence In The Rut Vocalizations Of Persian And European Fallow Deer, J. B. Stachowicz, E. Vannoni, B. J. Pitcher, Elodie F. Briefer, E. Geffen, A. G. Mcelligott

Veterinary Science and Medicine Collection

We conducted a study of the male rut vocalizations (groans) of two closely related species, Persian and European fallow deer. Persian fallow deer are endangered, restricted to Iran and Israel, and their rut vocalizations have never been studied. By contrast, European fallow deer are one of the most common deer species in the world, and have been the subject of numerous detailed studies. Persian bucks are approximately 16% larger than European bucks, and this can have important implications for vocalizations. Persian bucks were recorded in Israel, and European bucks were recorded in the UK and Ireland. We measured temporal, fundamental …


The Evolutionary History Of Cetacean Brain And Body Size, Stephen H. Montgomery, Jonathan H. Geisler, Michael R. Mcgowen, Charlotte Fox, Lori Marino, John Gatesy Nov 2013

The Evolutionary History Of Cetacean Brain And Body Size, Stephen H. Montgomery, Jonathan H. Geisler, Michael R. Mcgowen, Charlotte Fox, Lori Marino, John Gatesy

Veterinary Science and Medicine Collection

Cetaceans rival primates in brain size relative to body size and include species with the largest brains and biggest bodies to have ever evolved. Cetaceans are remarkably diverse, varying in both phenotypes by several orders of magnitude, with notable differences between the two extant suborders, Mysticeti and Odontoceti.We analyzed the evolutionary history of brain and body mass, and relative brain size measured by the encephalization quotient (EQ), using a data set of extinct and extant taxa to capture temporal variation in the mode and direction of evolution. Our results suggest that cetacean brain and body mass evolved under strong directional …


Fallow Bucks Get Hoarse: Vocal Fatigue As A Possible Signal To Conspecifics, Elisabetta Vannoni, Alan G. Mcelligott Jul 2009

Fallow Bucks Get Hoarse: Vocal Fatigue As A Possible Signal To Conspecifics, Elisabetta Vannoni, Alan G. Mcelligott

Veterinary Science and Medicine Collection

Many studies of sexually selected vocal communication assume that calls remain stable throughout the breeding season. However, during this period, physiological and social factors change and these can have strong effects on the structure of calls and calling rates. During the rut, fallow bucks, Dama dama, reduce their feeding and increase the time and energy spent on vocalizing and fighting to gain matings, and consequently their body condition declines greatly. The availability of matings and intensity of competition between males also change. Therefore, we predicted that male vocal signalling would vary over time in response to the changing intersexual and …


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 Dec 2007

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 …


Using Self-Organizing Maps To Recognize Acoustic Units Associated With Information Content In Animal Vocalizations, John Placer, C. N. Slobodchikoff, Jason Burns, Jeffrey Placer, Ryan Middleton May 2006

Using Self-Organizing Maps To Recognize Acoustic Units Associated With Information Content In Animal Vocalizations, John Placer, C. N. Slobodchikoff, Jason Burns, Jeffrey Placer, Ryan Middleton

Veterinary Science and Medicine Collection

Kohonen self-organizing neural networks, also called self-organizing maps (SOMs), have been used successfully to recognize human phonemes and in this way to aid in human speech recognition. This paper describes how SOMS also can be used to associate specific information content with animal vocalizations. A SOM was used to identify acoustic units in Gunnison’s prairie dog alarm calls that were vocalized in the presence of three different predator species. Some of these acoustic units and their combinations were found exclusively in the alarm calls associated with a particular predator species and were used to associate predator species information with individual …


Acoustic Structures In The Alarm Calls Of Gunnison’S Prairie Dogs, C. N. Slobodchikoff, J. Placer May 2006

Acoustic Structures In The Alarm Calls Of Gunnison’S Prairie Dogs, C. N. Slobodchikoff, J. Placer

Veterinary Science and Medicine Collection

Acoustic structures of sound in Gunnison’s prairie dog alarm calls are described, showing how these acoustic structures may encode information about three different predator species (red-tailed hawk—Buteo jamaicensis; domestic dog—Canis familaris; and coyote—Canis latrans). By dividing each alarm call into 25 equal-sized partitions and using resonant frequencies within each partition, commonly occurring acoustic structures were identified as components of alarm calls for the three predators. Although most of the acoustic structures appeared in alarm calls elicited by all three predator species, the frequency of occurrence of these acoustic structures varied among the alarm calls for the different predators, suggesting that …


Does Diving Limit Brain Size In Cetaceans?, Lori Marino, Daniel Sol, Kristen Toren, Louis Lefebvre Apr 2006

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 Dec 2004

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 …


Neuroanatomical Structure Of The Spinner Dolphin (Stenella Longirostris Orientalis) Brain From Magnetic Resonance Images, Lori Marino, Keith Sudheimer, William A. Mclellan, John I. Johnson Jul 2004

Neuroanatomical Structure Of The Spinner Dolphin (Stenella Longirostris Orientalis) Brain From Magnetic Resonance Images, Lori Marino, Keith Sudheimer, William A. Mclellan, John I. Johnson

Veterinary Science and Medicine Collection

High-resolution magnetic resonance (MR) images of the brain of an adult spinner dolphin (Stenella longirostris orientalis) were acquired in the coronal plane at 55 antero-posterior levels. From these scans a computergenerated set of resectioned virtual images in the two remaining orthogonal planes was constructed with the use of the VoxelView and VoxelMath (Vital Images, Inc.) programs. Neuroanatomical structures were labeled in all three planes, providing the first labeled anatomical description of the spinner dolphin brain.


Magnetic Resonance Images Of The Brain Of A Dwarf Sperm Whale (Kogia Simus), L. Marino, K. Sudheimer, D. A. Pabst, J. I. Johnson Jul 2003

Magnetic Resonance Images Of The Brain Of A Dwarf Sperm Whale (Kogia Simus), L. Marino, K. Sudheimer, D. A. Pabst, J. I. Johnson

Veterinary Science and Medicine Collection

Cetacean (dolphin, whale and porpoise) brains are among the least studied mammalian brains because of the difficulty of collecting and histologically preparing such relatively rare and large specimens. Among cetaceans, there exist relatively few studies of the brain of the dwarf sperm whale (Kogia simus). Magnetic resonance imaging (MRI) offers a means of observing the internal structure of the brain when traditional histological procedures are not practical. Therefore, MRI has become a critical tool in the study of the brain of cetaceans and other large species. This paper represents the first MRI-based anatomically labelled three-dimensional description of the dwarf sperm …


Neuroanatomy Of The Common Dolphin (Delphinus Delphis) As Revealed By Magnetic Resonance Imaging (Mri), L. Marino, Keith Sudheimer, D. Ann Pabst, William A. Mclellan, David Filsoof, John I. Johnson Dec 2002

Neuroanatomy Of The Common Dolphin (Delphinus Delphis) As Revealed By Magnetic Resonance Imaging (Mri), L. Marino, Keith Sudheimer, D. Ann Pabst, William A. Mclellan, David Filsoof, John I. Johnson

Veterinary Science and Medicine Collection

In this study, magnetic resonance (MR) images of the brain of an adult common dolphin (Delphinus delphis) were acquired in the coronal plane at 66 antero-posterior levels. From these scans a computer-generated set of resectioned virtual images in orthogonal planes was constructed using the programs VoxelView and VoxelMath (Vital Images, Inc., Michigan State Univ.). Sections in all three planes reveal major neuroanatomical structures. These structures in the adult common dolphin brain are compared with those from a fetal common dolphin brain from a previously published study as well as with MR images of adult brains of other odontocetes. …


Anatomical And Electrophysiological Analysis Of The Trigeminal Nerve In A Teleost Fish, Oncorhynchus Mykiss, Lynne U. Sneddon Feb 2002

Anatomical And Electrophysiological Analysis Of The Trigeminal Nerve In A Teleost Fish, Oncorhynchus Mykiss, Lynne U. Sneddon

Veterinary Science and Medicine Collection

The trigeminal nerve in the rainbow trout, Oncorhynchus mykiss, was examined for the presence of A-delta and C fibres. Sections of the three branches of the trigeminal nerve were found to comprise a range of fibre types including Adelta and C fibres. The size range of the cell bodies of the trigeminal ganglion reflected the fibre range since they correlated with the size range of axons in the nerve branches. Electrophysiological recordings of evoked activity from the ganglion confirmed the presence of these fibre types and the proportion of these mirrored the proportion of fibre types in the anatomical analyses. …


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 Dec 2001

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, …


Relative Volume Of The Cerebellum In Dolphins And Comparison With Anthropoid Primates, L. Marino, James K. Rilling, Shinko K. Lin, Sam H. Ridgway Oct 2000

Relative Volume Of The Cerebellum In Dolphins And Comparison With Anthropoid Primates, L. Marino, James K. Rilling, Shinko K. Lin, Sam H. Ridgway

Veterinary Science and Medicine Collection

According to the ‘developmental constraint hypothesis’ of comparative mammalian neuroanatomy, brain growth follows predictable allometric trends. Therefore, brain structures should scale to the entire brain in the same way across mammals. Evidence for a departure from this pattern for cerebellum volume has recently been reported among the anthropoid primates. One of the mammalian groups that has been neglected in tests of the ‘developmental constraint hypothesis’ is the cetaceans (dolphins, whales, and porpoises). Because many cetaceans possess relative brain sizes in the range of primates comparative tests of the ‘developmental constraint hypothesis’ across these two groups could help to delineate the …


Observations And Possible Function Of The Striking Anterior Coloration Pattern Of Galathea Intermedia (Crustacea: Decapoda: Anomura), J. M. Hall-Spencer, P. G. Moore, L. U. Sneddon Apr 1999

Observations And Possible Function Of The Striking Anterior Coloration Pattern Of Galathea Intermedia (Crustacea: Decapoda: Anomura), J. M. Hall-Spencer, P. G. Moore, L. U. Sneddon

Veterinary Science and Medicine Collection

Galathea intermedia is common, but cryptic, on Clyde maerl deposits where it lives in small groups of mixed sex and age, sharing shelters (typically dead Dosinia shells) to avoid predation. Its appearance is marked by six iridescent blue spots which may play an important role in intra- or interspecific interactions.


Social Deprivation Of Infant Rhesus Monkeys Alters The Chemoarchitecture Of The Brain: I. Subcortical Regions, Lee J. Martin, Dawn M. Spicer, Mark H. Lewis, John P. Gluck, Linda C. Cork Nov 1991

Social Deprivation Of Infant Rhesus Monkeys Alters The Chemoarchitecture Of The Brain: I. Subcortical Regions, Lee J. Martin, Dawn M. Spicer, Mark H. Lewis, John P. Gluck, Linda C. Cork

Veterinary Science and Medicine Collection

Rhesus monkeys (Macaca mulatta) reared during the first year of life without social contact develop persistent stereotyped movements, self-directed behaviors, and psychosocial abnormalities, but neurobiological mechanisms underlying the behaviors of socially deprived (SD) monkeys are unknown. Monkeys were reared in total social deprivation for the first 9 months of life; control monkeys were reared socially (SR) with mothers and peers. Subjects were killed at 19-24 yr of age. Because the behaviors of SD monkeys are reminiscent of changes in striatal or amygdalar function, we used immunocytochemistry for substance P (SP), leutine-enkephalin (LENK), somatostatin, calbindin, and tyrosine hydroxylase (TH) to evaluate …