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Full-Text Articles in Anatomy

Perception Of Emotional Valence In Horse Whinnies, Elodie Briefer, Roi Mandel, Anne-Laure Maigrot, Sabrina Briefer Freymond, Iris Bachmann, Edna Hillmann Jul 2019

Perception Of Emotional Valence In Horse Whinnies, Elodie Briefer, Roi Mandel, Anne-Laure Maigrot, Sabrina Briefer Freymond, Iris Bachmann, Edna Hillmann

Elodie Briefer, PhD

Background: Non-human animals often produce different types of vocalisations in negative and positive contexts (i.e. different valence), similar to humans, in which crying is associated with negative emotions and laughter is associated with positive ones. However, some types of vocalisations (e.g. contact calls, human speech) can be produced in both negative and positive contexts, and changes in valence are only accompanied by slight structural differences. Although such acoustically graded signals associated with opposite valence have been highlighted in some species, it is not known if conspecifics discriminate them, and if contagion of emotional valence occurs as a result. We tested …


Encoding Of Emotional Valence In Wild Boar (Sus Scrofa) Calls, Anne-Laure Maigrot, Edna Hillmann, Elodie Briefer Jul 2019

Encoding Of Emotional Valence In Wild Boar (Sus Scrofa) Calls, Anne-Laure Maigrot, Edna Hillmann, Elodie Briefer

Elodie Briefer, PhD

Measuring emotions in nonhuman mammals is challenging. As animals are not able to verbally report how they feel, we need to find reliable indicators to assess their emotional state. Emotions can be described using two key dimensions: valence (negative or positive) and arousal (bodily activation or excitation). In this study, we investigated vocal expression of emotional valence in wild boars (Sus scrofa). The animals were observed in three naturally occurring situations: anticipation of a food reward (positive), affiliative interactions (positive), and agonistic interactions (negative). Body movement was used as an indicator of emotional arousal to control for the effect of …


Human Induced Rotation And Reorganization Of The Brain Of Domestic Dogs, Taryn Roberts, Paul Mcgreevy, Michael Valenzuela Feb 2018

Human Induced Rotation And Reorganization Of The Brain Of Domestic Dogs, Taryn Roberts, Paul Mcgreevy, Michael Valenzuela

Paul McGreevy, PhD

Domestic dogs exhibit an extraordinary degree of morphological diversity. Such breed-to-breed variability applies equally to the canine skull, however little is known about whether this translates to systematic differences in cerebral organization. By looking at the paramedian sagittal magnetic resonance image slice of canine brains across a range of animals with different skull shapes (N = 13), we found that the relative reduction in skull length compared to width (measured by Cephalic Index) was significantly correlated to a progressive ventral pitching of the primary longitudinal brain axis (r = 0.83), as well as with a ventral shift in the position …


Dog Behavior Co-Varies With Height, Bodyweight And Skull Shape, Paul D. Mcgreevy, Dana Georgevsky, Johanna Carrasco, Michael Valenzuela, Deborah L. Duffy, James A. Serpell Feb 2018

Dog Behavior Co-Varies With Height, Bodyweight And Skull Shape, Paul D. Mcgreevy, Dana Georgevsky, Johanna Carrasco, Michael Valenzuela, Deborah L. Duffy, James A. Serpell

Paul McGreevy, PhD

Dogs offer unique opportunities to study correlations between morphology and behavior because skull shapes and body shape are so diverse among breeds. Several studies have shown relationships between canine cephalic index (CI: the ratio of skull width to skull length) and neural architecture. Data on the CI of adult, show-quality dogs (six males and six females) were sourced in Australia along with existing data on the breeds’ height, bodyweight and related to data on 36 behavioral traits of companion dogs (n = 8,301) of various common breeds (n = 49) collected internationally using the Canine Behavioral Assessment and Research Questionnaire …


Vocal Individuality And Species Divergence In The Contact Calls Of Banded Penguins, Livio Favaro, Claudia Gili, Cristiano Da Rugna, Guido Gnone, Chiara Fissore, Daniel Sanchez, Alan G. Mcelligott, Marco Gamba, Daniela Pessani Nov 2017

Vocal Individuality And Species Divergence In The Contact Calls Of Banded Penguins, Livio Favaro, Claudia Gili, Cristiano Da Rugna, Guido Gnone, Chiara Fissore, Daniel Sanchez, Alan G. Mcelligott, Marco Gamba, Daniela Pessani

Alan G. McElligott, PhD

Penguins produce contact calls to maintain social relationships and group cohesion. Such vocalisations have recently been demonstrated to encode individual identity information in the African penguin. Using a source-filter theory approach, we investigated whether acoustic cues of individuality can also be found in other Spheniscus penguins and the acoustic features of contact calls have diverged within this genus. We recorded vocalisations from two ex-situ colonies of Humboldt penguin and Magellanic penguin (sympatric and potentially interbreeding in the wild) and one ex-situ group of African penguins (allopatric although capable of interbreeding with the other two species in captivity). We measured 14 …


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 Nov 2017

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

Alan G. McElligott, PhD

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 …


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 Aug 2016

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

John P. Gluck, PhD

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 …


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 Aug 2016

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

Elodie Briefer, PhD

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 …


Food For Thought … Mechanistic Validation, Thomas Hartung, Sebastian Hoffman, Martin Stephens Jul 2016

Food For Thought … Mechanistic Validation, Thomas Hartung, Sebastian Hoffman, Martin Stephens

Martin Stephens, PhD

Validation of new approaches in regulatory toxicology is commonly defined as the independent assessment of the reproducibility and relevance (the scientific basis and predictive capacity) of a test for a particular purpose. In large ring trials, the emphasis to date has been mainly on reproducibility and predictive capacity (comparison to the traditional test) with less attention given to the scientific or mechanistic basis. Assessing predictive capacity is difficult for novel approaches (which are based on mechanism), such as pathways of toxicity or the complex networks within the organism (systems toxicology). This is highly relevant for implementing Toxicology for the 21st …


Acoustic Structures In The Alarm Calls Of Gunnison’S Prairie Dogs, C. N. Slobodchikoff, J. Placer Jun 2016

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

Con Slobodchikoff, PhD

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 …


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 Jun 2016

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

Con Slobodchikoff, PhD

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 …


Microhabitat Use Affects Brain Size And Structure In Intertidal Gobies, Gemma E. White, Culum Brown May 2016

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

Culum Brown, PhD

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 …


Variation In Brain Morphology Of Intertidal Gobies: A Comparison Of Methodologies Used To Quantitatively Assess Brain Volumes In Fish, Gemma E. White, Culum Brown May 2016

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

Culum Brown, PhD

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 …


Rescuing Perishable Neuroanatomical Information From A Threatened Biodiversity Hotspot: Remote Field Methods For Brain Tissue Preservation Validated By Cytoarchitectonic Analysis, Immunohistochemistry, And X-Ray Microcomputed Tomography, Daniel F. Hughes, Ellen M. Walker, Paul M. Gignac, Anais Martinez, Kenichiro Negishi, Carl S. Lieb, Eli Greenbaum, Arshad M. Khan May 2016

Rescuing Perishable Neuroanatomical Information From A Threatened Biodiversity Hotspot: Remote Field Methods For Brain Tissue Preservation Validated By Cytoarchitectonic Analysis, Immunohistochemistry, And X-Ray Microcomputed Tomography, Daniel F. Hughes, Ellen M. Walker, Paul M. Gignac, Anais Martinez, Kenichiro Negishi, Carl S. Lieb, Eli Greenbaum, Arshad M. Khan

Arshad M. Khan, Ph.D.

Biodiversity hotspots, which harbor more endemic species than elsewhere on Earth, are
increasingly threatened. There is a need to accelerate collection efforts in these regions
before threatened or endangered species become extinct. The diverse geographical, ecological,
genetic, morphological, and behavioral data generated from the on-site collection of
an individual specimen are useful for many scientific purposes. However, traditional methods
for specimen preparation in the field do not permit researchers to retrieve neuroanatomical
data, disregarding potentially useful data for increasing our understanding of brain
diversity. These data have helped clarify brain evolution, deciphered relationships between
structure and function, and revealed constraints …


Elucidation Of The Anatomy Of A Satiety Network: Focus On Connectivity Of The Parabrachial Nucleus In The Adult Rat, Györgyi Zséli, Barbara Vida, Anais Martinez, Ronald M. Lechan, Arshad M. Khan, Csaba Fekete Feb 2016

Elucidation Of The Anatomy Of A Satiety Network: Focus On Connectivity Of The Parabrachial Nucleus In The Adult Rat, Györgyi Zséli, Barbara Vida, Anais Martinez, Ronald M. Lechan, Arshad M. Khan, Csaba Fekete

Arshad M. Khan, Ph.D.

We hypothesized that brain regions showing neuronal activation after refeeding comprise major nodes in a satiety network, and tested this hypothesis with two sets of experiments. Detailed c-Fos mapping comparing fasted and refed rats was performed to identify candidate nodes of the satiety network. In addition to well-known feeding-related brain regions such as the arcuate, dorsomedial, and paraventricular hypothalamic nuclei, lateral hypothalamic area, parabrachial nucleus (PB), nucleus of the solitary tract and central amygdalar nucleus, other referring activated regions were also identified, such as the parastrial and parasubthalamic nuclei. To begin to understand the connectivity of the satiety network, the …


Investigation Of Van Gogh-Like 2 Mrna Regulation And Localisation In Response To Nociception In The Brain Of Adult Common Carp (Cyprinus Carpio), Siobhan C. Reilly, Anja Kipar, David J. Hughes, John P. Quinn, Andrew R. Cossins, Lynne U. Sneddon Aug 2015

Investigation Of Van Gogh-Like 2 Mrna Regulation And Localisation In Response To Nociception In The Brain Of Adult Common Carp (Cyprinus Carpio), Siobhan C. Reilly, Anja Kipar, David J. Hughes, John P. Quinn, Andrew R. Cossins, Lynne U. Sneddon

Lynne Sneddon, PhD

The Van Gogh-like 2 (vangl2) gene is typically associated with planar cell polarity pathways, which is essential for correct orientation of epithelial cells during development. The encoded protein of this gene is a transmembrane protein and is highly conserved through evolution. Van Gogh-like 2 was selected for further study on the basis of consistent regulation after a nociceptive stimulus in adult common carp and rainbow trout in a microarray study. An in situ hybridisation was conducted in the brain of mature common carp (Cyprinus carpio), 1.5 and 3 h after a nociceptive stimulus comprising of an acetic acid injection to …


Three Rs Approaches In The Production And Quality Control Of Fish Vaccines, Paul J. Midtlyng, Coenraad F.M. Hendriksen, Elisabeth Balks, Lukas Bruckner, Lawrence Elsken, Øystein Evensen, Kjetil Fyrand, Allison Guy, Marlies Halder, Penny Hawkins, Gunn Kisen, Anne Berit Romstad, Kira Salonius, Patrick Smith, Lynne U. Sneddon Aug 2015

Three Rs Approaches In The Production And Quality Control Of Fish Vaccines, Paul J. Midtlyng, Coenraad F.M. Hendriksen, Elisabeth Balks, Lukas Bruckner, Lawrence Elsken, Øystein Evensen, Kjetil Fyrand, Allison Guy, Marlies Halder, Penny Hawkins, Gunn Kisen, Anne Berit Romstad, Kira Salonius, Patrick Smith, Lynne U. Sneddon

Lynne Sneddon, PhD

The workshop on Three Rs Approaches in the Production and Quality Control of Fish Vaccines aimed a) to identify animal tests currently stipulated for the production and quality control of fish vaccines and to highlight animal welfare concerns associated with these tests; b) to identify viable options to replace, reduce, and refine animal use for fish vaccine testing; and c) to discuss the way forward and set out how the Three Rs may be implemented without jeopardizing the quality of the vaccines. The workshop participants -- experts from academia, regulatory authorities, a scientific animal welfare organization, and the fish vaccine …


Characterisation Of Chemosensory Trigeminal Receptors In The Rainbow Trout, Oncorhynchus Mykiss: Responses To Chemical Irritants And Carbon Dioxide, Jessica J. Mettam, Catherine R. Mccrohan, Lynne U. Sneddon Jul 2015

Characterisation Of Chemosensory Trigeminal Receptors In The Rainbow Trout, Oncorhynchus Mykiss: Responses To Chemical Irritants And Carbon Dioxide, Jessica J. Mettam, Catherine R. Mccrohan, Lynne U. Sneddon

Lynne Sneddon, PhD

Trigeminally innervated, mechanically sensitive chemoreceptors (M) were previously identified in rainbow trout, Oncorhynchus mykiss, but it is not known whether these receptors are responsive only to noxious, chemical irritants or have a general chemosensory function. This study aimed to characterise the stimulus–response properties of these receptors in comparison with polymodal nociceptors (P). Both P and M gave similar response profiles to acetic acid concentrations. The electrophysiological properties were similar between the two different afferent types. To determine whether the receptors have a nociceptive function, a range of chemical stimulants was applied to these receptors, including non-noxious stimuli such as ammonium …


Clinical Anesthesia And Analgesia In Fish, Lynne U. Sneddon Jul 2015

Clinical Anesthesia And Analgesia In Fish, Lynne U. Sneddon

Lynne Sneddon, PhD

Fish have become a popular experimental model and companion animal, and are also farmed and caught for food. Thus, surgical and invasive procedures in this animal group are common, and this review will focus on the anesthesia and analgesia of fish. A variety of anesthetic agents are commonly applied to fish via immersion. Correct dosing can result in effective anesthesia for acute procedures as well as loss of consciousness for surgical interventions. Dose and anesthetic agent vary between species of fish and are further confounded by a variety of physiological parameters (e.g., body weight, physiological stress) as well as environmental …


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

Lori Marino, Ph.D.

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, …


Relative Volume Of The Cerebellum In Dolphins And Comparison With Anthropoid Primates, L. Marino, James K. Rilling, Shinko K. Lin, Sam H. Ridgway Jun 2015

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

Lori Marino, PhD

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 …


The Evolutionary History Of Cetacean Brain And Body Size, Stephen H. Montgomery, Jonathan H. Geisler, Michael R. Mcgowen, Charlotte Fox, Lori Marino, John Gatesy May 2015

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

Lori Marino, PhD

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 …


Cetaceans And Primates: Convergence In Intelligence And Self-Awareness, Lori Marino Apr 2015

Cetaceans And Primates: Convergence In Intelligence And Self-Awareness, Lori Marino

Lori Marino, PhD

Cetaceans (dolphins, porpoises and whales) have been of greatest interest to the astrobiology community and to those interested in consciousness and selfawareness in animals. This interest has grown primarily from knowledge of the intelligence, language and large complex brains that many cetaceans possess. The study of cetacean and primate brain evolution and cognition can inform us about the contingencies and parameters associated with the evolution of complex intelligence in general, and, the evolution of consciousness. Striking differences in cortical organization in the brains of cetaceans and primates along with shared cognitive capacities such as self-awareness, culture, and symbolic concept comprehension, …


Eavesdropping By Bats: The Influence Of Echolocation Call Design And Foraging Strategy, Jonathan Balcombe, M. Brock Fenton Jun 2014

Eavesdropping By Bats: The Influence Of Echolocation Call Design And Foraging Strategy, Jonathan Balcombe, M. Brock Fenton

Jonathan Balcombe, PhD

We used playback presentations to free-flying bats of 3 species to assess the influence of echolocation call design and foraging strategy on the role of echolocation calls in communication. Near feeding sites over water, Myotis lucifugus and M. yumanensis responded positively only to echolocation calls of conspecifics. Near roosts, these bats did not respond before young of the year became volant, and after this responded to presentations of echolocation calls of similar and dissimilar design. At feeding sites Lasiurus borealis responded only to echolocation calls of conspecifics and particularly to "feeding buzzes". While Myotis, particularly subadults, appear to use the …


A Multivariate Model Of Stakeholder Preference For Lethal Cat Management, Dara M. Wald, Susan K. Jacobson Apr 2014

A Multivariate Model Of Stakeholder Preference For Lethal Cat Management, Dara M. Wald, Susan K. Jacobson

Dara Wald

Identifying stakeholder beliefs and attitudes is critical for resolving management conflicts. Debate over outdoor cat
management is often described as a conflict between two groups, environmental advocates and animal welfare advocates, but little is known about the variables predicting differences among these critical stakeholder groups. We administered a mail survey to randomly selected stakeholders representing both of these groups (n = 1,596) in Florida, where contention over the management of outdoor cats has been widespread. We used a structural equation model to evaluate stakeholder intention to support non-lethal management. The cognitive hierarchy model predicted that values influenced beliefs, which predicted …


Rapid Inversion: Running Animals And Robots Swing Like A Pendulum Under Ledges, Jean-Michel Mongeau, Brian Mcrae, Ardian Jusufi, Paul Birkmeyer, Aaron M. Hoover, Ronald Fearing, Robert J. Full Jul 2012

Rapid Inversion: Running Animals And Robots Swing Like A Pendulum Under Ledges, Jean-Michel Mongeau, Brian Mcrae, Ardian Jusufi, Paul Birkmeyer, Aaron M. Hoover, Ronald Fearing, Robert J. Full

Aaron M. Hoover

Escaping from predators often demands that animals rapidly negotiate complex environments. The smallest animals attain relatively fast speeds with high frequency leg cycling, wing flapping or body undulations, but absolute speeds are slow compared to larger animals. Instead, small animals benefit from the advantages of enhanced maneuverability in part due to scaling. Here, we report a novel behavior in small, legged runners that may facilitate their escape by disappearance from predators. We video recorded cockroaches and geckos rapidly running up an incline toward a ledge, digitized their motion and created a simple model to generalize the behavior. Both species ran …


A New Eusuchian Crocodyliform With Novel Cranial Integument And Its Significance For The Origin And Evolution Of Crocodylia, Casey Holliday, Nicholas Gardner Dec 2011

A New Eusuchian Crocodyliform With Novel Cranial Integument And Its Significance For The Origin And Evolution Of Crocodylia, Casey Holliday, Nicholas Gardner

Nicholas Gardner

Crocodyliforms were one of the most successful groups of Mesozoic tetrapods, radiating into terrestrial, semiaquatic and marine environments, while occupying numerous trophic niches, including carnivorous, insectivorous, herbivorous, and piscivorous species. Among these taxa were the enigmatic, poorly represented flat-headed crocodyliforms from the late Cretaceous of northern Africa. Here we report a new, giant crocodyliform from the early Late Cretaceous (Cenomanian) Kem Kem Formation of Morocco. Represented by a partial braincase, the taxon has an extremely long, flat skull with large jaw and craniocervical muscles. The skull roof is ridged and ornamented with a broad, rough boss surrounded by significant vascular …