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Investigating Genetic Differences Between Strains Of Janthinobacterium Lividum On Salamanders And In Their Environment, Rhiannon E. Black 2016 University of Tennessee - Knoxville

Investigating Genetic Differences Between Strains Of Janthinobacterium Lividum On Salamanders And In Their Environment, Rhiannon E. Black

University of Tennessee Honors Thesis Projects

No abstract provided.


Phylogenetics: Which Was First, Tsd Or Gsd?, Fredric J. Janzen, J. G. Krenz 2016 Iowa State University

Phylogenetics: Which Was First, Tsd Or Gsd?, Fredric J. Janzen, J. G. Krenz

Fredric Janzen

The basic challenge of evolutionary biology is to explain variation or the lack thereof, be it phenotypic, genetic, phy· logenetic, spatial, temporal, and so on. To illustrate, one gross generalization is that phenotypic traits we think of as being very important to organisms tend to be highly conserved (e.g .. binocular vision in vertebrates). probably because the genomic and developmental underpinnings are essentially fiXed. Thus, one striking feature about sex-determining mechanisms (SDMs), a fundamental aspect of sexual or· ganisms, is the enormous variety (Bull1983).


Modeling The Effects Of Climate Change–Induced Shifts In Reproductive Phenology On Temperature-Dependent Traits, Rory S. Telemeco, Karen C. Abbott, Fredric J. Janzen 2016 Iowa State University

Modeling The Effects Of Climate Change–Induced Shifts In Reproductive Phenology On Temperature-Dependent Traits, Rory S. Telemeco, Karen C. Abbott, Fredric J. Janzen

Fredric Janzen

By altering phenology, organisms have the potential to match life-history events with suitable environmental conditions. Because of this, phenological plasticity has been proposed as a mechanism whereby populations might buffer themselves from climate change. We examine the potential buffering power of advancing one aspect of phenology, nesting date, on sex ratio in painted turtles (Chrysemys picta), a species with temperature-dependent sex determination. We developed a modified constant temperature equivalent model that accounts for the effect of the interaction among climate change, oviposition date, and seasonal thermal pattern on temperature during sexual differentiation and thus on offspring sex ratio. Our results ...


Experimental Analysis Of An Early Life-History Stage: Selection On Size Of Hatchling Turtles, Fredric J. Janzen, John K. Tucker, Gary L. Paukstis 2016 Iowa State University

Experimental Analysis Of An Early Life-History Stage: Selection On Size Of Hatchling Turtles, Fredric J. Janzen, John K. Tucker, Gary L. Paukstis

Fredric Janzen

Life-history evolution in short-lived organisms has been investigated extensively, but little is known empirically about the causes of the different life-history strategies of long-lived organisms. To explore this issue, we conducted experiments to evaluate natural selection acting on key traits during an important life-history stage of the red-eared slider turtle (Trachemys scripta elegans). We reared eggs from 56 females in a seminatural common environment and released 356 of the resulting hatchlings in four replicates at a natural nesting area to assess offspring recapture probability as a measure of survivorship during the post-emergence migration. Larger body size of hatchling turtles was ...


Evolutionary Genetics: From Molecules To Morphology, Fredric J. Janzen 2016 Iowa State University

Evolutionary Genetics: From Molecules To Morphology, Fredric J. Janzen

Fredric Janzen

The past 35 years have witnessed a revolution in evolutionary genetics that, like the proverbial The Little Engine that Could going over the mountain pass, shows no signs of slowing, much less stopping. To a considerable extent, we owe much to one per­ son, Richard Lewontin, for getting this little train over the hump and conducting it while the masses have shoveled coal into the boiler. Indeed, few have had such a substantive and pervasive impact on evolutionary biology in general, and so this edited volume is a welcome and well-deserved tribute to the powerful and varied influence of Lewontin ...


Counterintuitive Density-Dependent Growth In A Long-Lived Vertebrate After Removal Of Nest Predators, Ricky-John Spencer, Fredric J. Janzen, Michael B. Thompson 2016 Iowa State University

Counterintuitive Density-Dependent Growth In A Long-Lived Vertebrate After Removal Of Nest Predators, Ricky-John Spencer, Fredric J. Janzen, Michael B. Thompson

Fredric Janzen

Examining the phenotypic and genetic underpinnings of life-history variation in long-lived organisms is central to the study of life-history evolution. Juvenile growth and survival are often density dependent in reptiles, and theory predicts the evolution of slow growth in response to low resources (resource-limiting hypothesis), such as under densely populated conditions. However, rapid growth is predicted when exceeding some critical body size reduces the risk of mortality (mortality hypothesis). Here we present results of paired, large-scale, five-year field experiments to identify causes of variation in individual growth and survival rates of an Australian turtle (Emydura macquarii) prior to maturity. To ...


Does Life History Affect Molecular Evolutionary Rates?, Gerardo A. Cordero, Fredric Janzen 2016 Iowa State University

Does Life History Affect Molecular Evolutionary Rates?, Gerardo A. Cordero, Fredric Janzen

Fredric Janzen

The molecular evolutionary rate measures the frequency with which DNA or protein sequence mutations are fixed (i.e., shared by most individuals) in a population. On the other hand, the mutation rate refers to the amount of change in a DNA or protein sequence for a given unit of time. These two intrinsically related processes have been key to our basic understanding of molecular evolution. For example, the molecular clock theory (Zuckerkandl & Pauling 1962) predicts an increase in fixed amino acid mutations of protein sequences as a function of time. The molecular evolutionary rate is then expected to be constant ...


Cephalopods Are Best Candidates For Invertebrate Consciousness, Jennifer A. Mather, Claudio Carere 2016 Psychology, University of Lethbridge

Cephalopods Are Best Candidates For Invertebrate Consciousness, Jennifer A. Mather, Claudio Carere

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

Insects might have been the first invertebrates to evolve sentience, but cephalopods were the first invertebrates to gain scientific recognition for it.


Caterpillars, Consciousness And The Origins Of Mind, Arthur S. Reber 2016 University of British Columbia

Caterpillars, Consciousness And The Origins Of Mind, Arthur S. Reber

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

A novel framework for the origins of consciousness and mind, the Cellular Basis of Consciousness (CBC), is presented. The model is based on a simple, perhaps radical axiom: subjectivity is an inherent feature of particular kinds of organic form. Experiential states, including those denoted as "mind" and "consciousness," are present in the most primitive species. The model has several conceptual and empirical virtues, among them: (a) it (re)solves the problem of how minds are created by brains ─ also known as the "Hard Problem" (Chalmers 1995) ─ by revealing that the apparent difficulty results from a category error, (b) it redirects ...


Graemeloweus, A New Scorpion Genus From Northern California, Usa (Scorpiones: Vaejovidae), Michael E. Soleglad, Victor Fet, Matthew R. Graham, Richard F. Ayrey 2016 Marshall University

Graemeloweus, A New Scorpion Genus From Northern California, Usa (Scorpiones: Vaejovidae), Michael E. Soleglad, Victor Fet, Matthew R. Graham, Richard F. Ayrey

Euscorpius

Genus Graemeloweus, gen. nov. (Scorpiones: Vaejovidae) is described from northern California, USA. The genus is composed of three species formerly placed in Pseudouroctonus: Graemeloweus iviei (Gertsch et Soleglad, 1972), comb. nov. (type species), G. glimmei (Hjelle, 1972), comb. nov., and G. maidu (Savary et Bryson, 2016), comb. nov. Major diagnostic characters of Graemeloweus include a non-bifurcated primary lamellar hook, the presence of a secondary lamellar hook, a complex mating plug with a two part base and an asymmetric crescent-shape barb, and the presence of a well-developed ventromedian (V2) carina on the pedipalp chela. Evidence is presented suggesting that Graemeloweus is ...


Addressing Misconceptions About Evolution, Sarah O'Leary-Driscoll, Don Dosch 2016 Illinois Mathematics and Science Academy

Addressing Misconceptions About Evolution, Sarah O'Leary-Driscoll, Don Dosch

Sarah O'Leary-Driscoll

"Leave with effective ways to identify and address misconceptions about evolution, with a particular focus on supporting explanations with evidence."


Animals Are Agents, Linda A.W. Brakel 2016 University of Michigan

Animals Are Agents, Linda A.W. Brakel

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

Mark Rowlands’s (2016) target article invites us to consider individuals in a broad subset of the non-human animal world as genuine persons. His account features animals reacting to salient environmental stimuli as Gibsonian affordances, which is indicative of “pre-reflective self-awareness.” He holds that such pre-reflective self-awareness is both “immune to error through misidentification” (Shoemaker, 1968) and a necessary precursor to reflective consciousness and personhood. I agree. In this commentary I hope to extend Rowlands’s work with a view in which agency is an even more fundamental precursor and one can (and should) consider individuals throughout the entire animal ...


Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Vi. Compsobuthus Vachon, 1949 (Buthidae), With A Description Of C. Eritreaensis Sp. N., František Kovařík, Graeme Lowe, Jana Plíšková, František Šťáhlavský 2016 Charles University

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Vi. Compsobuthus Vachon, 1949 (Buthidae), With A Description Of C. Eritreaensis Sp. N., František Kovařík, Graeme Lowe, Jana Plíšková, František Šťáhlavský

Euscorpius

All four Compsobuthus species of the Horn of Africa were newly collected, C. werneri firstly collected in Eritrea and C. eritreaensis sp. n. discovered during scorpiological expeditions in 2011–2016. Information is provided about their taxonomy, distribution, and ecology, fully complemented with color photos of live and preserved specimens, as well as their habitat. The hemispermatophore of C. eritreaensis sp. n. is illustrated and described. In addition to morphological analysis, we also describe the karyotype of C. eritreaensis sp. n. (2n=22).


A New Species Of Diplocentrus (Scorpionidae: Diplocentrinae) From Western Izabal, Guatemala, Luis F. de Armas, Rony E. Trujillo 2016 Universidad de San Carlos de Guatemala

A New Species Of Diplocentrus (Scorpionidae: Diplocentrinae) From Western Izabal, Guatemala, Luis F. De Armas, Rony E. Trujillo

Euscorpius

Diplocentrus izabal sp. n. is herein described on basis to one male (holotype) and two females from El Estor municipality, Izabal department, eastern Guatemala. It seems to be a close relative of Diplocentrus lachua Armas, Trujillo & Agreda, 2012, from which it differs by having carapace almost smooth, with anteromedian notch V-shaped; pectines with 11 teeth in both sexes, and carapace clearly longer than pedipalp manus and metasomal segment V (D. lachua has carapace minutely granulate, with anteromedian notch U-shaped; pectines with 13 teeth in the males (female unknown), and carapace as long as both pedipalp manus and metasomal segment V).


Implicit Mental Processes Are An Improbable Basis For Personhood, Michael L. Woodruff 2016 East Tennessee State University

Implicit Mental Processes Are An Improbable Basis For Personhood, Michael L. Woodruff

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

Rowlands argues that animals have implicit pre-reflective awareness and that this is adequate to create the unity of conscious thought required for personhood. For him pre-reflective awareness does not include intentionality and is probably an unconscious process. I suggest that his sense of implicit leads to significant difficulties for his argument and that including intentionality in the definition of a first-person perspective provides a stronger base for viewing animals as persons.


Are Animals Persons?, Mark Rowlands 2016 University of Miami

Are Animals Persons?, Mark Rowlands

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

It is orthodox to suppose that very few, if any, nonhuman animals are persons. The category “person” is restricted to self-aware creatures: humans (above a certain age) and possibly some of the great apes and cetaceans. I argue that this orthodoxy should be rejected, because it rests on a mistaken conception of the kind of self-awareness relevant to personhood. Replacing this with a sense of self-awareness that is relevant requires us to accept that personhood is much more widely distributed through the animal kingdom.


Insects Have The Capacity For Subjective Experience, Colin Klein, Andrew B. Barron 2016 Macquarie University, Australia

Insects Have The Capacity For Subjective Experience, Colin Klein, Andrew B. Barron

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

To what degree are non-human animals conscious? We propose that the most meaningful way to approach this question is from the perspective of functional neurobiology. Here we focus on subjective experience, which is a basic awareness of the world without further reflection on that awareness. This is considered the most basic form of consciousness. Tellingly, this capacity is supported by the integrated midbrain and basal ganglia structures, which are among the oldest and most highly conserved brain systems in vertebrates. A reasonable inference is that the capacity for subjective experience is both widespread and evolutionarily old within the vertebrate lineage ...


Utilitarianism Generalized To Include Animals, Yew-Kwang Ng 2016 Nanyang Technological University

Utilitarianism Generalized To Include Animals, Yew-Kwang Ng

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

In response to the seventeen commentaries to date on my target article on reducing animal suffering, I propose that the term “welfarism” (when used pejoratively by animal advocates) should be qualified as “anthropocentric welfarism” so as to leave “welfarism” simpliciter to be used in its generic sense of efforts to improve conditions for those who need it. Welfarism in this benign sense — even in its specific utilitarian form (maximizing the sum total of net welfare) with long-term future effects and effects on others (including animals) appropriately taken into account — should be unobjectionable (even if not considered sufficient by all advocates ...


Cross-Species Mind-Reading, Stevan Harnad 2016 Université du Québec à Montréal & University of Southampton

Cross-Species Mind-Reading, Stevan Harnad

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

We can never be sure anyone else is sentient. But we can be sure enough in the case of other people, nonhuman primates, mammals, birds, fish, lower vertebrates and invertebrates as to make scepticism academic and otiose (not to mention monumentally cruel). The only genuinely uncertain kinds of cases are jellyfish, microbes and plants. The rest is not about whether but what they are feeling.


My Orgasms Cannot Be Traded Off Against Others’ Agony, Stevan Harnad 2016 Université du Québec à Montréal & University of Southampton

My Orgasms Cannot Be Traded Off Against Others’ Agony, Stevan Harnad

Animal Sentience: An Interdisciplinary Journal on Animal Feeling

Only I can calculate my own welfare as net pleasure minus pain. No one else can do that calculation for me – nor for a population, and especially not averaging across some individuals’ pleasure and other individuals’ pain. Pain and pleasure are incommensurable and only pain matters morally. To maximize welfare is to minimize pain.


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