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The Early History Of Chance In Evolution, Charles H. Pence Oct 2014

The Early History Of Chance In Evolution, Charles H. Pence

Faculty Publications

Work throughout the history and philosophy of biology frequently employs ‘chance’, ‘unpredictability’, ‘probability’, and many similar terms. One common way of understanding how these concepts were introduced in evolution focuses on two central issues: the first use of statistical methods in evolution (Galton), and the first use of the concept of “objective chance” in evolution (Wright). I argue that while this approach has merit, it fails to fully capture interesting philosophical reflections on the role of chance expounded by two of Galton's students, Karl Pearson and W.F.R. Weldon. Considering a question more familiar from contemporary philosophy of biology—the relationship between …


Natural Selection Canalizes Expression Variation Of Environmentally Induced Plasticity-Enabling Genes, Joseph R. Shaw, Thomas H. Hampton, Benjamin L. King, Andrew Whitehead, Fernando Galvez, Robert H. Gross, Nathan Keith, Emily Notch, Dawoon Jung, Stephen P. Glaholt, Celia Y. Chen, John K. Colbourne, Bruce A. Stanton Jan 2014

Natural Selection Canalizes Expression Variation Of Environmentally Induced Plasticity-Enabling Genes, Joseph R. Shaw, Thomas H. Hampton, Benjamin L. King, Andrew Whitehead, Fernando Galvez, Robert H. Gross, Nathan Keith, Emily Notch, Dawoon Jung, Stephen P. Glaholt, Celia Y. Chen, John K. Colbourne, Bruce A. Stanton

Faculty Publications

© 2014 The Author. Many organisms survive fluctuating and extreme environmental conditions by manifesting multiple distinct phenotypes during adulthood by means of developmental processes that enable phenotypic plasticity. We report on the discovery of putative plasticity-enabling genes that are involved in transforming the gill of the euryhaline teleost fish, Fundulus heteroclitus, from its freshwater to its seawater gill-type, a process that alters both morphology and function. Gene expression that normally enables osmotic plasticity is inhibited by arsenic. Gene sets defined by antagonistic interactions between arsenic and salinity show reduced transcriptional variation among individual fish, suggesting unusually accurate and precise regulatory …


Model-Based Tests Of Historical Demography And Species Delimitation In The Caribbean Coral Reef Sponge Callyspongia, Melissa Barrett Debiasse Jan 2014

Model-Based Tests Of Historical Demography And Species Delimitation In The Caribbean Coral Reef Sponge Callyspongia, Melissa Barrett Debiasse

LSU Doctoral Dissertations

Coral reefs are the most productive and species rich ecosystems in the ocean yet we lack knowledge about the distribution of genetic variation the within and among reef species, particularly for the sponges (Porifera). My dissertation describes how genetic variation at mitochondrial and nuclear genes is partitioned among and within species in the sponge genus Callyspongia. I compared patterns of genetic diversity and population subdivision in the mitochondrial and nuclear genomes of one species, C. vaginalis, in Florida (Chapter 2). Previous work revealed three divergent mitochondrial lineages, but nuclear alleles did not correspond to either mitochondrial clade or geography. Coalescent …


The Louisiana Sciences Education Act's Impact On High School Science, Gareth Mitchell Jan 2014

The Louisiana Sciences Education Act's Impact On High School Science, Gareth Mitchell

LSU Master's Theses

Over the last two decades, extensive research has been conducted concerning the legality and effectiveness of teaching opposing viewpoints on controversial topics in science education. However, one of the most important aspects of this dilemma has been disregarded: the effect it has on individual teachers in their unique environments. The purpose of this research was to analyze teacher’s comprehension of recent state legislation as well as how it impacts their instruction. This quantitative approach took place through an online survey of secondary science teachers in biology, which focuses on their teaching experience, understanding of the Louisiana Science Education Act of …


Bridging Research And Education: A Look Into The Evolutionary History Of Batfishes And How Museum Exhibits Can Be Used To Engage The Public, Valerie Anestazia Derouen Jan 2014

Bridging Research And Education: A Look Into The Evolutionary History Of Batfishes And How Museum Exhibits Can Be Used To Engage The Public, Valerie Anestazia Derouen

LSU Master's Theses

The objective of this thesis was not only to contribute to our understanding of batfishes but to also show interesting and educational ways research can be presented to the general public. The first part of this project examines the evolutionary history of batfishes. Batfishes (Ogcocephalidae) are an understudied, group of marine anglerfishes that are dorsoventrally flattened and have an illicium and esca used to attract prey. Relationships among these taxa, as well as the position of Ogcocephalidae within Lophiiformes, remain poorly understood, with previous studies showing conflicting, and poorly resolved results. The timing of divergence and depth of origination in …


Systematics And Species Delimitation In New Guinea Skink Species Complexes (Squamata: Scincidae), Eric Nikolaus Rittmeyer Jan 2014

Systematics And Species Delimitation In New Guinea Skink Species Complexes (Squamata: Scincidae), Eric Nikolaus Rittmeyer

LSU Doctoral Dissertations

Though among the most controversial topics in systematic and evolutionary biology, species are a fundamental unit in biology, and are utilized by and critical to a wide variety of studies in the life sciences. Despite this importance, little work has focused on developing and examining objective methods for species delimitation until recently. Further, New Guinea and the surrounding regions are among the most diverse and geologically complex regions globally, yet the region remains poorly explored biologically, and little work has examined the evolutionary history of the fauna in the region. To investigate the influence of factors such as sampling intensity, …