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Full-Text Articles in Life Sciences

Octopi-Ing A Unique Niche In Comparative Psychology, Jennifer Vonk Jan 2019

Octopi-Ing A Unique Niche In Comparative Psychology, Jennifer Vonk

Animal Sentience

Mather’s work has been fundamental in informing scientists of the relatively mysterious behavior and cognition of an understudied group of animals – the cephalopods. This work helps to fill a gap in the comparative literature that has historically sought evidence for complex behavior only in species that are closely related to humans or share important ecological features such as social complexity.


Our Brains Make Us Out To Be Unique In Ways We Are Not, Matthew J. Criscione, Julian Paul Keenan Jan 2019

Our Brains Make Us Out To Be Unique In Ways We Are Not, Matthew J. Criscione, Julian Paul Keenan

Animal Sentience

Humans have long viewed themselves in a favorable light. This bias is consistent with a general pattern of self-enhancement. Neural systems in the medial prefrontal cortex underlie this way of thinking, which, even when false, may be beneficial for survival. It is hence not surprising that we often disregard contrary evidence in believing ourselves superior.


Digging Biomechanics In Geomyoid Rodents, Alexis Moore Crisp May 2018

Digging Biomechanics In Geomyoid Rodents, Alexis Moore Crisp

UNLV Theses, Dissertations, Professional Papers, and Capstones

Subterranean digging behaviors provide opportunities for protection, access to prey, and predator avoidance for a diverse array of vertebrates, yet studies of the biomechanics of burrowing have been limited by the technical challenges of measuring kinetics and kinematics of animals moving within a substrate. Prior studies of burrowing have recorded a single axis of x-ray video and/or force. However, empirical observations show that burrowing is not restricted to a single axis or plane. I describe a new system called a ‘tunnel-tube’ for measuring 3D reaction force during burrowing. This tunnel-tube has two separate tubes, one ‘entry tube’ that has ...


Animal Suicide: An Account Worth Giving?, Irina Mikhalevich Jan 2018

Animal Suicide: An Account Worth Giving?, Irina Mikhalevich

Animal Sentience

Peña-Guzmán (2017) argues that empirical evidence and evolutionary theory compel us to treat the phenomenon of suicide as continuous in the animal kingdom. He defends a “continuist” account in which suicide is a multiply-realizable phenomenon characterized by self-injurious and self-annihilative behaviors. This view is problematic for several reasons. First, it appears to mischaracterize the Darwinian view that mind is continuous in nature. Second, by focusing only on surface-level features of behavior, it groups causally and etiologically disparate phenomena under a single conceptual umbrella, thereby reducing the account’s explanatory power. Third, it obscures existing analyses of suicide in biomedical ethics ...


Can They Suffer?, Todd K. Shackelford Jan 2018

Can They Suffer?, Todd K. Shackelford

Animal Sentience

We should treat sentient nonhuman animals as worthy of moral consideration, not because we share an evolutionary history with them, but because they can suffer. As Chapman & Huffman (2018) argue, humans are not uniquely disconnected from other species. We should minimize the suffering we inflict on sentient beings — whether human or nonhuman — not because they, too, are tool-makers or have sophisticated communication systems, but because they, too, can suffer, and suffering is bad.


Consciousness Is Not Inherent In But Emergent From Life, Jon Mallatt, Todd E. Feinberg Jan 2017

Consciousness Is Not Inherent In But Emergent From Life, Jon Mallatt, Todd E. Feinberg

Animal Sentience

Reber’s theory of the cellular basis of consciousness (CBC) is right to emphasize that we should study consciousness (sentience) in its simplest form, taking its evolution into account. However, not enough evidence is presented to support CBC’s unorthodox claim that even simple, one-celled organisms are conscious. As pointed out by other commentators, the CBC seems to be based on outdated ideas about evolution and does not acknowledge that consciousness could be an evolutionary novel feature. Such emergent features are abundant in living organisms. We review our own emergentist solution, in which consciousness evolved in the elaborating nervous systems ...


Cognitive Continuity In Cognitive Dissonance, David R. Brodbeck, Madeleine I. R. Brodbeck Jan 2017

Cognitive Continuity In Cognitive Dissonance, David R. Brodbeck, Madeleine I. R. Brodbeck

Animal Sentience

Zentall’s (2016) model of cognitive dissonance is compatible with cognitive continuity between humans and nonhumans. It may help explain cognitive dissonance-like behavior in many species, including humans. It is also consistent with Tinbergen’s (1963) ‘four whys’ in ethological explanation.


The Emotional Brain Of Fish, Sonia Rey Planellas Jan 2017

The Emotional Brain Of Fish, Sonia Rey Planellas

Animal Sentience

Woodruff (2017) analyzes structural homologies and functional equivalences between the brains of mammals and fish to understand where sentience and social cognition might reside in teleosts. He compares neuroanatomical, neurophysiological and behavioural correlates. I discuss current advances in the study of fish cognitive abilities and emotions, and advocate an evolutionary approach to the underlying basis of sentience in teleosts.


How Could Consciousness Emerge From Adaptive Functioning?, Max Velmans Sep 2016

How Could Consciousness Emerge From Adaptive Functioning?, Max Velmans

Animal Sentience

The sudden appearance of consciousness that Reber posits in creatures with flexible cell walls and motility rather than non-flexible cells walls and no motility involves an evolutionary discontinuity. This kind of “miracle” is required by all “discontinuity” theories of consciousness. To avoid miraculous emergence, one may need to consider continuity theories, which accept that different forms of consciousness and material functioning co-evolve but assume the existence of consciousness to be primal in the way that matter and energy are assumed to be primal in physics.


“Cellular Basis Of Consciousness”: Not Just Radical But Wrong, Brian Key Sep 2016

“Cellular Basis Of Consciousness”: Not Just Radical But Wrong, Brian Key

Animal Sentience

Reber (2016) attempts to resuscitate an obscure and outdated hypothesis referred to as the “cellular basis of consciousness” that was originally formulated by the author nearly twenty years ago. This hypothesis proposes that any organism with flexible cell walls, a sensitivity to its surrounds, and the capacity for locomotion will possess the biological foundations of mind and consciousness. Reber seeks to reduce consciousness to a fundamental property inherent to individual cells rather than to centralised nervous systems. This commentary shows how this hypothesis is based on supposition, false premises and a misunderstanding of evolutionary theory. The cellular basis of consciousness ...


Beginnings: Physics, Sentience And Luca, Carolyn A. Ristau Sep 2016

Beginnings: Physics, Sentience And Luca, Carolyn A. Ristau

Animal Sentience

According to Reber’s model, Cellular Basis of Consciousness (CBC), sentience had its origins in a unicellular organism and is an inherent property of living, mobile organic forms. He argues by analogy to basic physical forces which he considers to be inherent properties of matter; I suggest that they are instead the stuff of scientific investigation in physics. I find no convincing argument that sentience had to begin in endogenously mobile cells, a criterial attribute of the originator cell(s)for sentience according to CBC. Non-endogenously mobile cells, (i.e., plants or precursors) in a moving environment would suffice. Despite ...


Fish Pain: An Inconvenient Truth, Culum Brown May 2016

Fish Pain: An Inconvenient Truth, Culum Brown

Culum Brown, Ph.D.

Whether fish feel pain is a hot political topic. The consequences of our denial are huge given the billions of fish that are slaughtered annually for human consumption. The economic costs of changing our commercial fishery harvest practices are also likely to be great. Key outlines a structure-function analogy of pain in humans, tries to force that template on the rest of the vertebrate kingdom, and fails. His target article has so far elicited 34 commentaries from scientific experts from a broad range of disciplines; only three of these support his position. The broad consensus from the scientific community is ...


Slavery, Welfare And The Sixth Extinction, Stephen R. Clark Mar 2016

Slavery, Welfare And The Sixth Extinction, Stephen R. Clark

Animal Sentience

Ng’s laudable concern for animal welfare would be welcome to any sensible slave-owner wishing to preserve his investment. What welfarism – for slave-owners and animal husbandmen – fails to call into question is whether we have the right to breed, hold captive and kill animals at all: If it matters, as the widely recognized slogan of ‘Five Freedoms’ suggests, that animals have the chance to live a ‘normal’ life, then more matters than keeping them ‘happy’ in subjection. Their lives – and also the lives of wild things – also deserve respect.


Pain-Capable Neural Substrates May Be Widely Available In The Animal Kingdom, Edgar T. Walters Jan 2016

Pain-Capable Neural Substrates May Be Widely Available In The Animal Kingdom, Edgar T. Walters

Animal Sentience

Neural and behavioral evidence from diverse species indicates that some forms of pain may be generated by coordinated activity in networks far smaller than the cortical pain matrix in mammals. Studies on responses to injury in squid suggest that simplification of the circuitry necessary for conscious pain might be achieved by restricting awareness to very limited information about a noxious event, possibly only to the fact that injury has occurred, ignoring information that is much less important for survival, such as the location of the injury. Some of the neural properties proposed to be critical for conscious pain in mammals ...


Fish Pain: An Inconvenient Truth, Culum Brown Jan 2016

Fish Pain: An Inconvenient Truth, Culum Brown

Animal Sentience

Whether fish feel pain is a hot political topic. The consequences of our denial are huge given the billions of fish that are slaughtered annually for human consumption. The economic costs of changing our commercial fishery harvest practices are also likely to be great. Key outlines a structure-function analogy of pain in humans, tries to force that template on the rest of the vertebrate kingdom, and fails. His target article has so far elicited 34 commentaries from scientific experts from a broad range of disciplines; only three of these support his position. The broad consensus from the scientific community is ...


Female And Male Life Tables For Seven Wild Primate Species, Anne M. Bronikowski, Marina Cords, Susan C. Alberts, Jeanne Altmann, Diane K. Brockman, Linda M. Fedigan, Anne Pusey, Tara Stoinski, Karen B. Strier, William F. Morris Jan 2016

Female And Male Life Tables For Seven Wild Primate Species, Anne M. Bronikowski, Marina Cords, Susan C. Alberts, Jeanne Altmann, Diane K. Brockman, Linda M. Fedigan, Anne Pusey, Tara Stoinski, Karen B. Strier, William F. Morris

Ecology, Evolution and Organismal Biology Publications

We provide male and female census count data, age-specific survivorship, and female age-specific fertility estimates for populations of seven wild primates that have been continuously monitored for at least 29 years: sifaka (Propithecus verreauxi) in Madagascar; muriqui (Brachyteles hypoxanthus) in Brazil; capuchin (Cebus capucinus) in Costa Rica; baboon (Papio cynocephalus) and blue monkey (Cercopithecus mitis) in Kenya; chimpanzee (Pan troglodytes) in Tanzania; and gorilla (Gorilla beringei) in Rwanda. Using one-year age-class intervals, we computed point estimates of age-specific survival for both sexes. In all species, our survival estimates for the dispersing sex are affected by heavy censoring. We also calculated ...


Pain And Fish Welfare, Eliane Gonçalves-De-Freitas Jan 2016

Pain And Fish Welfare, Eliane Gonçalves-De-Freitas

Animal Sentience

The evolutionary approach of Key’s (2016) target article, generically comparing humans with fish of all kinds, is simplistic. The author ignores published research on structural and molecular aspects of pain in fish. The target article reads more like a selective polemic against fish welfare than an even-handed analysis.


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, Ph.D.

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 ...


Life History Evolution And Adaptive Radiation Of Hemidactyliine Salamanders, Travis Ryan, R. Bruce Feb 2015

Life History Evolution And Adaptive Radiation Of Hemidactyliine Salamanders, Travis Ryan, R. Bruce

Travis J. Ryan

T.J. Ryan and R.C. Bruce's contribution to: The Biology of Plethodontid Salamanders, R. C. Bruce, R. G. Jaeger, and L. D. Houck, eds. Kluwer Academic/Plenum Publishers, New York.


Widespread Rapid Reductions In Body Size Of Adult Salamanders In Response To Climate Change, Nicholas M. Caruso, Michael W. Sears, Dean C. Adams, Karen R. Lips Jun 2014

Widespread Rapid Reductions In Body Size Of Adult Salamanders In Response To Climate Change, Nicholas M. Caruso, Michael W. Sears, Dean C. Adams, Karen R. Lips

Ecology, Evolution and Organismal Biology Publications

Reduction in body size is a major response to climate change, yet evidence in globally imperiled amphibians is lacking. Shifts in average population body size could indicate either plasticity in the growth response to changing climates through changes in allocation and energetics, or through selection for decreased size where energy is limiting. We compared historic and contemporary size measurements in 15 Plethodon species from 102 populations (9450 individuals) and found that six species exhibited significant reductions in body size over 55 years. Biophysical models, accounting for actual changes in moisture and air temperature over that period, showed a 7.1 ...


Integrating, Developing, And Testing Methods To Generate More Cohesive Approaches To Biogeographic Inference, Mallory Elizabeth Eckstut May 2013

Integrating, Developing, And Testing Methods To Generate More Cohesive Approaches To Biogeographic Inference, Mallory Elizabeth Eckstut

UNLV Theses, Dissertations, Professional Papers, and Capstones

As a fundamental component of the developing discipline of conservation biogeography, broadscale analyses of biotic assembly and disassembly across multiple temporal and spatial scales provide an enhanced understanding of how geologic transformations and climate oscillations have shaped extant patterns of biodiversity. As with any scientific field, there are limitations in the case of biogeographic historical reconstructions. Historical reconstructions are only as robust as the theoretical underpinnings of the methods of reconstruction (including data collection, quality, analysis, and interpretation). Nevertheless, historical reconstructions of species distributions can help inform our understanding of how species respond to environmental change.

My dissertation takes a ...


Determining The Composition Of The Dwelling Tubes Of Antarctic Pterobranchs, Lukasz J. Sewera Apr 2011

Determining The Composition Of The Dwelling Tubes Of Antarctic Pterobranchs, Lukasz J. Sewera

Honors Projects

Pterobranchs are a group of marine invertebrates within the Hemichordata, which share characteristics with both chordates and echinoderms. Pterobranchs live in colonies of secreted tubes, coenicia, which are composed of a gelatinous material of unknown composition. Visually, the tubes appear similar to the tunic of tunicates, a group of invertebrates within the Chordata. The nonproteinaceous tunic of tunicates is composed of cellulose, which is unusual. The goal of this study was to determine the composition of the pterobranch coenicium. Some aspects of pterobranch phylogeny are still unclear even after multiple molecular and morphological studies. Identification of any new shared characteristics ...


Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney Dec 2010

Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney

Ryan Kerney

The concept of novelty in evolutionary biology pertains to multiple tiers of biological organization from behavioral and morphological changes to changes at the molecular level. Identifying novel features requires assessments of similarity (homology and homoplasy) of relationships (phylogenetic history) and of shared developmental and genetic pathways or networks. After a brief discussion of how novelty is used in recent literature, we discuss whether the evolutionary approach to homology and homoplasy initially formulated by Lankester in the 19th century informs our understanding of novelty today. We then discuss six examples of morphological features described in the recent literature as novelties, and ...


On The Evolution Of Sexually Transmitted Diseases In Birds, Michael Lombardo Jul 2010

On The Evolution Of Sexually Transmitted Diseases In Birds, Michael Lombardo

Michael P Lombardo

"The definitive version is available at www.blackwell-synergy.com".

Sexually transmitted diseases (STDs) in animals are caused by pathogens that are transmitted during copulation. Birds have played an important role in the development of STD-centered theories of mating behavior. However, it is not known whether STDs exist in wild bird populations. While the avian cloaca with its dual functions of gamete transfer and excretion seemingly predisposes birds for the evolution of STDs, the life history patterns of most birds (i.e., seasonal breeders with relatively brief annual periods of sexual activity) suggest otherwise. The importance of STDs as selective forces ...


Morphological Differences Among Eyeless Amphipods In The Genus Stygobromus Dwelling In Different Subterranean Habitats, David C. Culver, John R. Holsinger, Mary C. Christman, Tanja Pipan Jan 2010

Morphological Differences Among Eyeless Amphipods In The Genus Stygobromus Dwelling In Different Subterranean Habitats, David C. Culver, John R. Holsinger, Mary C. Christman, Tanja Pipan

Biological Sciences Faculty Publications

The amphipod genus Stygobromus occurs in a variety of subterranean habitats in North America, including caves, phreatic (groundwater) lakes, and superficial subterranean habitats (seeps and epikarst). The habitats share the absence of light but differ in other features, such as pore size of the habitat, available food, and degree of seasonality. Measurements of body size, antennal size, and antennal segment number of type specimens were compared for 56 species occurring in the eastern United States. Except for differences in body size, differences among species in the four different habitats were not significant. Body size was related to relative pore size ...


On The Tendency Of Varieties To Depart Indefinitely From The Original Type (1858), Alfred Russel Wallace Jan 2009

On The Tendency Of Varieties To Depart Indefinitely From The Original Type (1858), Alfred Russel Wallace

Alfred Russel Wallace Classic Writings

No abstract provided.


On The Law Which Has Regulated The Introduction Of New Species (1855), Alfred Russel Wallace Jan 2009

On The Law Which Has Regulated The Introduction Of New Species (1855), Alfred Russel Wallace

Alfred Russel Wallace Classic Writings

No abstract provided.


Molecular Systematics And Phylogeography Of The Genus Richardsonius, Derek Dee Houston Jan 2009

Molecular Systematics And Phylogeography Of The Genus Richardsonius, Derek Dee Houston

UNLV Theses, Dissertations, Professional Papers, and Capstones

The complex geological and climatic events that significantly altered the landscape throughout the Cenozoic Era impacted the diversification of many North American taxa, including freshwater fishes. Here, I employ an array of phylogenetic analyses using a multiple gene tree approach to address several questions regarding the phylogenetic relationships of the North American cyprinid genus Richardsonius and two other closely related genera, Clinostomus and Iotichthys. I also use divergence time estimates generated using fossil calibrations to qualitatively assess the phylogeographic implications of evolution within and among these three genera. Mitochondrial and nuclear DNA sequences show a sister relationship between Iotichthys and ...


Runx2 Is Essential For Larval Hyobranchial Cartilage Formation In Xenopus Laevis, Ryan Kerney, Joshua Gross, James Hanken Dec 2006

Runx2 Is Essential For Larval Hyobranchial Cartilage Formation In Xenopus Laevis, Ryan Kerney, Joshua Gross, James Hanken

Ryan Kerney

The vertebrate transcription factor protein Runx2 is regarded as a “master regulator” of bone formation due to the dramatic loss of the osseous skeleton in the mouse homozygous knockout. However, Runx2 mRNA also is expressed in the pre-hypertrophic cartilaginous skeleton of the mouse and chicken, where its developmental function is largely unknown. Several tiers of Runx2 regulation exist in the mouse, any of which may account for its seeming biological inactivity during early stages of skeletogenesis. Unlike mouse and chicken, zebrafish require Runx2 function in early cartilage differentiation. The present study reveals that the earlier functional role of Runx2 in ...


Unilateral Eye Closure And Interhemispheric Eeg Asymmetry During Sleep In The Pigeon (Columba Livia), Niels Rattenborg, Charles Amlaner, Steven Lima Dec 2000

Unilateral Eye Closure And Interhemispheric Eeg Asymmetry During Sleep In The Pigeon (Columba Livia), Niels Rattenborg, Charles Amlaner, Steven Lima

Charles J. Amlaner

Aquatic mammals (i.e., Cetaceans, eared seals and manatees) and birds show interhemispheric asymmetries (IA) in slow-wave sleep-related electroencephalographic (EEG) activity, suggesting that the depth of sleep differs between hemispheres. In birds, an association between unilateral eye closure and IA has been reported in five species from three orders (i.e., Galliformes, Charadriiformes, and Anseriformes). Moreover, unilateral eye closure has been observed during behaviorally defined sleep in 29 species from 13 avian orders, suggesting that birds in general display IA during sleep. Despite the apparent prevalence of unilateral eye closure and IA in birds, previous work did not detect A ...