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Epigenetic Contributions To Early Life History Variation In Chinook Salmon, Clare J. Venney
Epigenetic Contributions To Early Life History Variation In Chinook Salmon, Clare J. Venney
Electronic Theses and Dissertations
DNA methylation has been proposed as an epigenetic, evolutionary mechanism for acclimation, transgenerational plasticity, and local adaptation without changes in DNA sequence. In this thesis, I assess the highly targeted evolutionary nature of DNA methylation in Chinook salmon from the tissue to the population level, with important implications for organism survival and evolution. First, I developed a PCR-based bisulfite assay for Next-Generation sequencing for genes involved in growth, development, immune function, stress response, and metabolism (Chapter 2). Locus- and tissue-specific methylation was assessed in inbred and outbred Chinook salmon at two developmental stages (fry and yearling). This chapter established DNA …
Simulations And Modelling For Biological Invasions, Ryan D. Scott
Simulations And Modelling For Biological Invasions, Ryan D. Scott
Electronic Theses and Dissertations
Biological invasions are characterized by the movement of organisms from their native geographic region to new, distinct regions in which they may have significant impacts. Biological invasions pose one of the most serious threats to global biodiversity, and hence significant resources are invested in predicting, preventing, and managing them. Biological systems and processes are typically large, complex, and inherently difficult to study naturally because of their immense scale and complexity. Hence, computational modelling and simulation approaches can be taken to study them. In this dissertation, I applied computer simulations to address two important problems in invasion biology. First, in invasion …
Why Are Salmon Red? Proximate And Ultimate Causes Of Flesh Pigmentation In Chinook Salmon, Sarah Jean Lehnert
Why Are Salmon Red? Proximate And Ultimate Causes Of Flesh Pigmentation In Chinook Salmon, Sarah Jean Lehnert
Electronic Theses and Dissertations
Carotenoids are responsible for the characteristic red eggs, skin and flesh of salmonids. Although carotenoids are thought to provide salmon with many benefits, carotenoid pigmentation has not evolved in all, or even the majority of fishes, thus highlighting our lack of understanding of the evolutionary costs and benefits associated with the pigment. In nature, Chinook salmon (Oncorhynchus tshawytscha) exhibit extreme variation in carotenoid utilization due to genetic polymorphisms that affect carotenoid deposition into the flesh, skin and eggs, consequently resulting in two colour morphs (red and white). Chinook salmon are thus an ideal model species to study carotenoid pigmentation evolution. …
Dominance In Multi-Population Cultural Algorithms, Santosh Upadhyayula
Dominance In Multi-Population Cultural Algorithms, Santosh Upadhyayula
Electronic Theses and Dissertations
We propose a new approach that can be used for solving the knowledge migration issue in multi-population cultural algorithms (MPCA). In this study we introduce a new method to enable the migration of individuals from one population to another using the concept of complete dominance applied to MPCA. The MPCA’s artificial population comprises of agents that belong to a certain sub-population. In this work we create a dominance multi population cultural algorithm (D-MPCA) with a network of populations that implements a dominance strategy. We hypothesize that the evolutionary advantage of dominance can help improve the performance of MPCA in general …
Function And Evolution Of Plumage Traits In Trogons (Aves Trogoniformes), And The Importance Of Parameterization In Visual Models, Pierre-Paul Bitton
Function And Evolution Of Plumage Traits In Trogons (Aves Trogoniformes), And The Importance Of Parameterization In Visual Models, Pierre-Paul Bitton
Electronic Theses and Dissertations
In this dissertation, I investigated the function and evolution of plumage-based visual signals in trogons (Trogoniformes), and assessed the influence of individual parameters in the receptor-noise model of colour discriminability. In Chapter 2, I investigated the function of tail raising in the elegant trogon. For this purpose, I used observational and experimental data collected in Costa Rica. Results demonstrated that tail raising in the elegant trogon is a multifunctional signal that targets both conspecifics and heterospecifics. Specifically, trogons used this behaviour during intra and intersexual interactions, and the experiment confirmed that tail raising is a pursuit-deterrent signal. In Chapter 3, …
Compromise As Deep Virtue: Evolution And Some Limits Of Argumentation, Philip Rose
Compromise As Deep Virtue: Evolution And Some Limits Of Argumentation, Philip Rose
OSSA Conference Archive
If argument forms evolve then the possible existence of localized argument forms may create an interpretive impasse between locally distinct argument communities. Appeal to evolutionarily ‘deep’ argument forms may help, but might be strained in cases where emergent argument forms are not reducible to their base conditions. Overcoming such limits presupposes the virtue of compromise, suggesting that compromise may stand as ‘deep virtue’ within argumentative forms of life.
Emerging Truth And The Defeat Of Scientific Racism, Mark Weinstein
Emerging Truth And The Defeat Of Scientific Racism, Mark Weinstein
OSSA Conference Archive
This paper looks at the attack on scientific racism in the 20th century by a group of social and biological scientists. I will utilize the apparatus of my model of emerging truth to show how even in complex socially conditioned argumentation the ultimate virtue is seeking the truth through increasingly powerful logical connections and deeply embedded warrants.
Speciation In Ancient Lakes: Insights From The Copepods Of Sulawesi, James Joseph Vaillant
Speciation In Ancient Lakes: Insights From The Copepods Of Sulawesi, James Joseph Vaillant
Electronic Theses and Dissertations
One of the fundamental questions in biology is the origin of species. Considerable insights into the processes that drive speciation have come from ancient lake systems. In this thesis, I present insights into speciation processes by investigating the species radiations of the ancient Malili Lakes of Sulawesi, Indonesia. The nature of adaptive radiations in the lakes suggests that intraspecific competition for extremely limited resources has driven taxa to adapt to specific habitats and food sources. The copepod populations of Sulawesi reveal that colonization order governs the geographic distribution of zooplankton in freshwater ecosystems. In many Malili Lakes taxa, hybridization between …
Evolution, Cognition And Argumentation, Cristian Santibanez Yanez, Michael A. Gilbert
Evolution, Cognition And Argumentation, Cristian Santibanez Yanez, Michael A. Gilbert
OSSA Conference Archive
Sperber and Mercier (2009, 2010) maintain that argumentation is a meta-representational module. In their evolutionary view of argumentation, the function of this module would be to regulate the flow of information between interlocutors through persuasiveness on the side of the communicator and epistemic vigilance on the side of the audience. The aim of this paper is to discuss this definition of argumen-tation by analyzing what they mean by “communicator’s persuasiveness” and “audience epistemic vigilance”
Xarx2: An Aristaless Homolog That Regulates Brain Regionalization During Development In Xenopus Laevis, Marian Wolanski, Farhad Khosrowshahian, Le Kelly, Michael J. Crawford
Xarx2: An Aristaless Homolog That Regulates Brain Regionalization During Development In Xenopus Laevis, Marian Wolanski, Farhad Khosrowshahian, Le Kelly, Michael J. Crawford
Biological Sciences Publications
The aristaless-related gene, Arx, plays a fundamental role in patterning the brain in humans and mice. Arx mutants exhibit lissencephaly among other anomalies. We have cloned a Xenopus aristaless homolog that appears to define specific regions of the developing forebrain. xArx2 is transcribed in blastula through neurula stages, and comes to be restricted to the ventra and lateral telencephalon, lateral diencephalon, neural floor plate of the anterior spinal cord, and somites. In this respect, Arx2 expresses in regions similar to Arx with the exception of the somites. Overexpression enlarges the telencephalon, and interference by means of antisense morpholino-mediated translation knockdown …