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2019

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Articles 61 - 90 of 193

Full-Text Articles in Evolution

Arterial Distribution Of The Human Aorta: An Examination Of The Evolutionary, Developmental, And Physiological Bases Of Asymmetry., Brandon Oddo, Cooker Storm Mar 2019

Arterial Distribution Of The Human Aorta: An Examination Of The Evolutionary, Developmental, And Physiological Bases Of Asymmetry., Brandon Oddo, Cooker Storm

Seaver College Research And Scholarly Achievement Symposium

The study of anatomy contends that “form follows function”; a disciplinary theme purporting that anatomical structures (i.e., cells, tissues, and organs) have a shape that serves its proper function. With this in mind, it is unclear why human arterial distribution off the aortic arch is asymmetrical, while the corresponding venous anatomy is symmetrical. We investigated the evolutionary, developmental, and physiological bases for the asymmetry of aortic arch branches in humans. First, we investigated the cardiovascular anatomy of ancestral species to determine if, and at what level, anatomical divergence (from aortic symmetry to asymmetry) occurs. Second, we examined the formation of …


Genomics Based Approaches To Fungal Evolution, Aaron J. Robinson, Donald O. Natvig Mar 2019

Genomics Based Approaches To Fungal Evolution, Aaron J. Robinson, Donald O. Natvig

Biology ETDs

Advances in DNA sequencing and data analysis make it possible to address questions in population genetics and evolution at the genomic level. Fungi are excellent subjects for such studies, because they are found in diverse environments, have short generation times, can be maintained in culture and have relatively small genomes. My research employed genetic approaches using a variety of sequencing technologies and methods of analysis to explore questions in fungal evolution.

In one study, I explored the genetics behind differences in thermotolerance between isolates of Neurospora discreta from Alaska and New Mexico. Isolates from the two states exhibited differences in …


Area And Distance From Mainland Affect In Different Ways Richness And Phylogenetic Diversity Of Snakes In Atlantic Forest Coastal Islands, José Thales Da Motta Portillo, Lilian Sayuri Ouchi-Melo, Lucas Batista Crivellari, Thiago Alves Lopes De Oliveira, Ricardo J. Sawaya, Leonardo Da Silva Duarte Mar 2019

Area And Distance From Mainland Affect In Different Ways Richness And Phylogenetic Diversity Of Snakes In Atlantic Forest Coastal Islands, José Thales Da Motta Portillo, Lilian Sayuri Ouchi-Melo, Lucas Batista Crivellari, Thiago Alves Lopes De Oliveira, Ricardo J. Sawaya, Leonardo Da Silva Duarte

Publications and Research

Aim: The Theory of Island Biogeography posits that ecological and evolutionary processes regulate species richness of isolated areas. We assessed the influences of an island area and distance from the mainland on species richness, phylogenetic diversity, and phylogenetic composition of snakes on coastal islands.

Location: Coastal islands of the megadiverse Atlantic Forest in southeastern Brazil.

Methods: We compiled the species composition of 17 coastal islands in southeastern Brazil. Species richness and phylogenetic diversity were calculated for each island. Phylogenetic composition was measured using principal coordinates of phylogenetic structure. We then employed generalized linear models to test the influence of …


Phylogeny And Evolution Of Swallows (Hirundinidae) With A Transcriptomic Perspective On Seasonal Migration, Clare Elisabeth Brown Mar 2019

Phylogeny And Evolution Of Swallows (Hirundinidae) With A Transcriptomic Perspective On Seasonal Migration, Clare Elisabeth Brown

LSU Doctoral Dissertations

Evolutionary biology seeks to understand the forces that have generated and shaped patterns of diversity. In this dissertation, I investigated phylogenetic relationships and the evolution of three traits—migration, nest-type, and geographic distribution—in the swallow family (Hirundinidae), a globally distributed group of about 85 species of aerial insectivorous birds. I first applied a dataset of several thousand ultraconserved element (UCE) loci to reconstructing the phylogeny of the New World genus Tachycineta. Three methods of phylogenetic inference produced topologically discordant trees, but post-inference analyses provided evidence that the tree produced by maximum likelihood analysis of a concatenated data matrix is the most …


An Endemic Species In A Protected Area: Euscorpius Carpathicus (L., 1767) In The Cozia National Park, Romania (Scorpiones: Euscorpiidae), Severus-Daniel Covaciu-Marcov, Sára Ferenţi Mar 2019

An Endemic Species In A Protected Area: Euscorpius Carpathicus (L., 1767) In The Cozia National Park, Romania (Scorpiones: Euscorpiidae), Severus-Daniel Covaciu-Marcov, Sára Ferenţi

Euscorpius

In 2016-2018, we identified 48 distribution records of Euscorpius carpathicus in the Cozia National Park, from the Romanian Southern Carpathians. The Carpathian scorpion was found between 300 and 847 m a.s.l., in forested regions, being more numerous in the lower areas situated along the Olt River. E. carpathicus is a native species in the region; it populates natural areas with low human impact.


A Review Of Orthochirus From Turkey, Iraq, And Iran (Khoozestan, Ilam, And Lorestan Provinces), With Descriptions Of Three New Species (Scorpiones: Buthidae), František Kovařík, Ersen Aydın Yağmur, Victor Fet, Fenik S. Hussen Feb 2019

A Review Of Orthochirus From Turkey, Iraq, And Iran (Khoozestan, Ilam, And Lorestan Provinces), With Descriptions Of Three New Species (Scorpiones: Buthidae), František Kovařík, Ersen Aydın Yağmur, Victor Fet, Fenik S. Hussen

Euscorpius

Three new species, Orthochirus fomichevi sp. n. from Turkey and Iraq, O. gantenbeini sp. n. from Iran (Khoozestan Province), and O. navidpouri sp. n. from Iran (Khoozestan and Lorestan Provinces) are described, compared with other Orthochirus species from the region, and fully illustrated with color photos. Lectotype of O. mesopotamicus Birula, 1918 stat. n. from Iran (Khoozestan Province) is designated. Emended diagnoses are given for O. iranus Kovařík, 2004, O. iraqus Kovařík, 2004, O. mesopotamicus Birula, 1918 stat. n., and O. zagrosensis Kovařík, 2004. A key and a distribution map are included.


Trypanothacus Gen. N., A New Genus Of Burrowing Scorpion From The Arabian Peninsula (Scorpiones: Buthidae), Graeme Lowe, František Kovařík, Mark Stockmann, František Šťáhlavský Feb 2019

Trypanothacus Gen. N., A New Genus Of Burrowing Scorpion From The Arabian Peninsula (Scorpiones: Buthidae), Graeme Lowe, František Kovařík, Mark Stockmann, František Šťáhlavský

Euscorpius

We define a new fossorial buthid genus Trypanothacus gen. n., similar to Buthacus Birula, 1908, differing primarily in telson shape, with a bulbous vesicle and aculeus shorter than the vesicle, and in heavier dentition on metasomal segments II–III and IV. The new genus includes two species: T. barnesi sp. n. from Oman and T. buettikeri (Hendrixson, 2006) comb. n. from Saudi Arabia, the latter transferred from Buthacus. We provide detailed illustrations of both species from preserved materials, and in vivo habitus and natural habitat are shown for T. barnesi sp. n.. Information is also provided on ecology and captive rearing …


Scorpions Of Iran (Arachnida, Scorpiones). Part X. Alborz, Markazi And Tehran Provinces With A Description Of Orthochirus Carinatus Sp. N. (Buthidae), Shahrokh Navidpour, František Kovařík, Michael Soleglad, Victor Fet Feb 2019

Scorpions Of Iran (Arachnida, Scorpiones). Part X. Alborz, Markazi And Tehran Provinces With A Description Of Orthochirus Carinatus Sp. N. (Buthidae), Shahrokh Navidpour, František Kovařík, Michael Soleglad, Victor Fet

Euscorpius

Nine species of scorpions belonging to two families are reported from the Alborz, Markazi and Tehran Provinces of Iran. Of these, Compsobuthus kaftani Kovařík, 2003 is recorded from Tehran Province for the first time; Compsobuthus matthiesseni (Birula, 1905) is recorded from Alborz Province for the first time; Hottentotta saulcyi (Simon, 1880) is recorded for Alborz and Markazi Provinces for the first time; Iranobuthus krali Kovařík, 1997 is recorded for Tehran Province for the first time; Mesobuthus eupeus eupeus (C. L. Koch, 1839) is recorded from Alborz, Markazi and Tehran Provinces for the first time; Odontobuthus doriae (Thorell, 1876) is recorded …


The Legacy Of Natural Species And Substantial Form For Thomistic Evolution, James R. Hofmann Feb 2019

The Legacy Of Natural Species And Substantial Form For Thomistic Evolution, James R. Hofmann

Forum Lectures

Exploration of theistic evolution within a Thomistic framework has taken on the label of Thomistic evolution. Although the conceptual boundaries of this approach are not precise, a historical trajectory of its scholastic methodology can be traced back to the views of Aquinas himself. An enduring central concept in this tradition has been the idea of substantial form. For Aquinas, distinct substantial forms were associated with the kinds of animals and plants that have no prior ancestry and are ascribed to God's production during the Genesis days of adornment. Later in the tradition, the early twentieth century Jesuit Erich Wasmann referred …


Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xix. Pandiborellius Meidensis (Karsch, 1879) And Pandinurus Fulvipes Sp. N. (Scorpionidae) From Somaliland., František Kovařík, Graeme Lowe, Tomáš Mazuch Feb 2019

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xix. Pandiborellius Meidensis (Karsch, 1879) And Pandinurus Fulvipes Sp. N. (Scorpionidae) From Somaliland., František Kovařík, Graeme Lowe, Tomáš Mazuch

Euscorpius

The male of Pandiborellius meidensis (Karsch, 1879) is introduced for the first time and illustrated in detail with color photos, and sexual dimorphism and occurrence of the species are discussed. Pandinurus fulvipes sp. n. from Somaliland is described and fully complemented with color photos of live and preserved specimens, as well as of its habitat.


Chaerilus Alberti Sp. N. From Malaysia (Scorpiones: Chaerilidae), František Kovařík Feb 2019

Chaerilus Alberti Sp. N. From Malaysia (Scorpiones: Chaerilidae), František Kovařík

Euscorpius

Chaerilus alberti sp. n. from Malaysia (Cameron Highlands) is described and fully illustrated with color photographs of preserved specimens, as well as of their habitat. Males of C. alberti sp. n. have a unique shape of chela which is stout with the manus swollen anteriorly. They are compared to other species from Southeast Asia, from all of which C. alberti sp. n. differs by the shape of pedipalp chela parallel or swollen posteriorly or medially. Pedipalp chela is illustrated with color photographs of 21 of these species.


Activation Of The Bile Acid Pathway And No Observed Antimicrobial Peptide Sequences In The Skin Of A Poison Frog, Megan L. Civitello, Robert Denton, Michael A. Zasloff, John H. Malone Feb 2019

Activation Of The Bile Acid Pathway And No Observed Antimicrobial Peptide Sequences In The Skin Of A Poison Frog, Megan L. Civitello, Robert Denton, Michael A. Zasloff, John H. Malone

Biology Publications

The skin secretions of many frogs have genetically-encoded, endogenous antimicrobial peptides (AMPs). Other species, especially aposematic poison frogs, secrete exogenously derived alkaloids that serve as potent defense molecules. The origins of these defense systems are not clear, but a novel bileacid derived metabolite, tauromantellic acid, was recently discovered and shown to be endogenous in poison frogs (Mantella, Dendrobates, and Epipedobates). These observations raise questions about the evolutionary history of AMP genetic elements, the mechanism and function of tauromatellic acid production, and links between these systems. To understand the diversity and expression of AMPs among frogs, we assembled skin transcriptomes of …


Phylogenetic History Of The Amy Gene Cluster In Catarrhines, Christian M. Gagnon Feb 2019

Phylogenetic History Of The Amy Gene Cluster In Catarrhines, Christian M. Gagnon

Theses and Dissertations

This study phylogenetically analyzed 30 AMY-related genes from 11 primates. The results show the gradual expansion of the AMY gene family which could have allowed primates to adapt to various ecological landscapes and maximize energy intake from starch-rich foods in periods of food scarcity.


The Morphology And Evolution Of The Primate Brachial Plexus, Brian M. Shearer Feb 2019

The Morphology And Evolution Of The Primate Brachial Plexus, Brian M. Shearer

Dissertations, Theses, and Capstone Projects

Primate evolutionary history is inexorably linked to the evolution of a broad array of locomotor adaptations that have facilitated the clade’s invasion of new niches. Researchers studying the evolution of primates and of their individual locomotor adaptations have traditionally relied on bony morphology – a practical choice given the virtual non-existence of any other type of tissue in the fossil record. However, this focus downplays the potential importance of the many other structures involved in locomotion, such as muscle, cartilage, and neural tissue, which may each be influenced by separate selective forces because of their different roles in facilitating movement. …


A New Semidesert Microtityus Kjellesvig-Waering, 1966 (Scorpiones: Buthidae) From Southeast Cuba, Greater Antilles., Rolando Teruel Jan 2019

A New Semidesert Microtityus Kjellesvig-Waering, 1966 (Scorpiones: Buthidae) From Southeast Cuba, Greater Antilles., Rolando Teruel

Euscorpius

A new species of the buthid scorpion genus Microtityus Kjellesvig-Waering, 1966, is herein described from specimens of both sexes collected at three nearby localities in the western part of the Guantánamo Bay Area, southeast Cuba. It belongs in the "jaumei" species-group of the subgenus Microtityus (Parvabsonus) Armas, 1974 and is very peculiar not only by its external morphology (very distinct from its other Cuban congeners), but also by the unusual habitat where it occurs in and seems to be restricted to (dry and hot cactus scrub on volcanic sandy plain). The present contribution reinforces the position of this genus as …


Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xviii. Gint Banfasae Sp. N. From Somaliland (Buthidae), František Kovařík, Graeme Lowe Jan 2019

Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xviii. Gint Banfasae Sp. N. From Somaliland (Buthidae), František Kovařík, Graeme Lowe

Euscorpius

Gint banfasae sp. n. from Somaliland is described and compared with other species of the genus. Additional information is provided on the taxonomy and distribution of the genus Gint, fully complemented with color photos of specimens of both sexes of the new species, as well as of their habitat. Included is a key for Gint.


Cichlid Size Vs Flow Rate, Amy E. Naumovski Jan 2019

Cichlid Size Vs Flow Rate, Amy E. Naumovski

STAR Program Research Presentations

Cichlids are a diverse group of fish that are known for their prenatal and postnatal care of their eggs and frys (baby fish). This unique characteristic creates a limitation on the amount of eggs a cichlid can lay and protect, which is particulalry effected by the size of the eggs. Cichlids have a large variance in their egg size, which correlates to a large variance in their fry size. This project explores the trade offs cichlids make in egg size and fry size by specifically testing the ability of varying sized cichlids to swim in different flow rates. This could …


Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen Jan 2019

Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen

STAR Program Research Presentations

Leptasterias spp. is a species complex of small, six rayed, predatory sea stars that inhabit rocky intertidal communities along the Pacific coast of North America. A developmental mode of brooding their young, rather than broadcasting for planktonic development, limits dispersal away from the natal area, and may also result in fine scale local adaptation of populations. Local adaptation may lead to morphological and behavioral differences among populations, specifically towards the most available prey. Within the rocky intertidalthere are zones of high and low wave impact which create microhabitats with their own selective forces. In areas of high wave impact, stars …


Social Learning Through Associative Processes: A Computational Theory, Johan Lind, Stefano Ghirlanda, Magnus Enquist Jan 2019

Social Learning Through Associative Processes: A Computational Theory, Johan Lind, Stefano Ghirlanda, Magnus Enquist

Publications and Research

Social transmission of information is a key phenomenon in the evolution of behaviour and in the establishment of traditions and culture. The diversity of social learning phenomena has engendered a diverse terminology and numerous ideas about underlying learning mechanisms, at the same time that some researchers have called for a unitary analysis of social learning in terms of associative processes. Leveraging previous attempts and a recent computational formulation of associative learning, we analyse the following learning scenarios in some generality: learning responses to social stimuli, including learning to imitate; learning responses to non-social stimuli; learning sequences of actions; learning to …


Trade-Offs Shape Carotenoid-Based Color Variation In Redheaded Pine Sawfly (Neodiprion Lecontei) Larvae, Maranda Gaines Jan 2019

Trade-Offs Shape Carotenoid-Based Color Variation In Redheaded Pine Sawfly (Neodiprion Lecontei) Larvae, Maranda Gaines

Lewis Honors College Capstone Collection

Carotenoids serve various ecological roles in animals including coloration, immune responses, and vision. Carotenoid-derived coloration is greatly emphasized in the literature, particularly relating to mate choice and aposematic warning. However, the trade-offs between the color and non-color functions of carotenoids are not thoroughly explored. In the redheaded pine sawfly (Neodiprion lecontei), some larval populations have yellow pigmentation, using carotenoids derived from their diets for aposematic warning coloration. Other larval populations are white in color, having genetically lost the ability to produce the yellow pigment. Because carotenoids are essential to life functions in both the yellow and white populations, we aim …


Changes In North American Mammal Niche Preferences From The Late Pleistocene To The Present, Silvia Pineda-Munoz, Anikó Tóth, S. Kathleen Lyons, Yue Wang, Jenny Mcguire Jan 2019

Changes In North American Mammal Niche Preferences From The Late Pleistocene To The Present, Silvia Pineda-Munoz, Anikó Tóth, S. Kathleen Lyons, Yue Wang, Jenny Mcguire

School of Biological Sciences: Presentations

Human population has exponentially grown since the last glaciation, especially across temperate areas with easy access to water sources, excluding mammal species from their former habitats. Thus, we anticipate a change in environmental niche preferences for temperature and precipitation as increased human population forces mammal species into more extreme climates within their environmental tolerances. For our study, we collected species occurrences from 20,000 ybp to the present for 59 North American mammal species. We inferred temperature and precipitation for each location using paleoclimate simulations (CCSM3). Overall, we found that mammals now live in areas that are warmer and dryer on …


Multiple Connections Between Amazonia And Atlantic Forest Shaped The T Phylogenetic And Morphological Diversity Of Chiasmocleis Mehely, 1904 (Anura: Microhylidae: Gastrophryninae), Rafael O. De Sá, João Filipe Riva Tonini, Hannah Van Huss, Alex Long, Travis Cuddy, Mauricio C. Forlani, Pedro L.V. Peloso, Hussam Zaher, Célio F.B. Haddad Jan 2019

Multiple Connections Between Amazonia And Atlantic Forest Shaped The T Phylogenetic And Morphological Diversity Of Chiasmocleis Mehely, 1904 (Anura: Microhylidae: Gastrophryninae), Rafael O. De Sá, João Filipe Riva Tonini, Hannah Van Huss, Alex Long, Travis Cuddy, Mauricio C. Forlani, Pedro L.V. Peloso, Hussam Zaher, Célio F.B. Haddad

Biology Faculty Publications

Chiasmocleis is the most species-rich genus of Neotropical microhylids. Herein, we provide the first comprehensive multilocus phylogeny for the genus, including all but 3 of the 34 recognized species and multiple individuals per species. We discuss cryptic speciation, species discovery, patterns of morphological evolution, and provide a historical biogeographic analysis to account for the current distribution of the genus. Diversification of Chiasmocleis from other New World microhylids began during the Eocene, app. 40 mya, in forested areas, and current diversity seems to be a product of recurrent connections between the Atlantic Forest and Amazonia. Small-sized species evolved independently three times …


Insects And The Evolution Of Developmental Pathways: Functional Analysis Of Genetic Sex Determination Mechanisms In Oncopeltus Fasciatus, Josefine Just Jan 2019

Insects And The Evolution Of Developmental Pathways: Functional Analysis Of Genetic Sex Determination Mechanisms In Oncopeltus Fasciatus, Josefine Just

Honors Theses

Natural selection alters genetic pathways over evolutionary time. However, different pathways have been shown to maintain mutations at varying rates, leading to different levels of conservation across developmental pathways. Sex determination pathways, in particular, show vast diversity across animals despite the fundamental conservation of biological sex itself. Here, I investigated the sex determination pathway of the hemimetabolous insect, Oncopeltus fasciatus. The large milkweed bug, O. fasciatus, is part of the order Hemiptera, which provides a relevant outgroup study to other insects in which sex determination has been studied to date. I studied three sex determination genes, intersex, fruitless …


Genetic Analysis Of A Parasite Contact Zone In The Southwestern United States, Tanner Storbeck Jan 2019

Genetic Analysis Of A Parasite Contact Zone In The Southwestern United States, Tanner Storbeck

Honors Program Theses

Studies of cophylogeny (the mirroring of the evolutionary histories of two independent species) lies at the interface of ecology and evolution and therefore is inherently interesting to biologists. The actual mechanisms that lead to patterns cophylogeny are poorly understood. Chewing lice (Trichodectidae) and pocket gophers (Geomyidae) are a model system for the study of cophylogeny. The question to be addressed in this study centers around the fine-scale interactions between pocket gophers and chewing lice in the Southwest United States and whether different louse species actually hybridize within a zone of potential contact. DNA microsatellite techniques, DNA sequencing, PCR, and gel …


Transgenerational Plasticity Is Sex-Dependent And Persistent In Yellow Moneyflower (Mimulus Guttatus), Kayla Akkerman Jan 2019

Transgenerational Plasticity Is Sex-Dependent And Persistent In Yellow Moneyflower (Mimulus Guttatus), Kayla Akkerman

All Master's Theses

Transgenerational phenotypic plasticity, whereby environmental cues experienced by parents alter the phenotype of their progeny, has now been documented in diverse organisms. Transmission of environmentally determined responses is known to occur through both maternal and paternal gametes, but the underlying mechanisms have rarely been compared. In addition, the persistence of induction over multiple generations appears to vary widely but has been characterized for relatively few systems. Yellow monkeyflower (Mimulus guttatus) is known to exhibit transgenerational induction of increased glandular trichome production in response to simulated insect damage. Here we test for differences between maternal and paternal transmission of …


Symbiotic Bacteria Can Colonize Closely-Related, But Not Distantly-Related Species Of Its Host Dictyostelium Discoideum, Rory Vu Mather Jan 2019

Symbiotic Bacteria Can Colonize Closely-Related, But Not Distantly-Related Species Of Its Host Dictyostelium Discoideum, Rory Vu Mather

Undergraduate Research Symposium Posters

Some of the closest interactions between organisms can be found within symbioses, where different individuals live in close physiological contact and either benefit or harm the other. A powerful kind of benefit comes when bacterial symbionts produce amino acids or provide digestive capabilities outside the host’s ability, in essence taking advantage of the other’s genetic catalog. One such symbiosis is that of the social amoeba Dictyostelium discoideum and its bacterial symbionts Burkholderia agricolaris, Burkholderia hayleyella, and Burkholderia bonneia. In this symbiosis, Burkholderia provide the capability of carrying food bacteria to their host, an advantageous trait when bacterial food is rare. …


Ecology, Monogamy, And The Evolution Of Animal Families, Jacqueline Rae Dillard Jan 2019

Ecology, Monogamy, And The Evolution Of Animal Families, Jacqueline Rae Dillard

Theses and Dissertations--Biology

Family-living has been recognized as a necessary prerequisite for the evolution of advanced cooperative societies, yet the evolutionary and ecological processes that drive the coupling of different forms of cooperation in family-based societies are still poorly understood. In my dissertation, I investigate the correlated evolution of parental care, monogamy, and cooperative breeding in a variety of family-based taxa. I explore the mating and social behavior of family-living beetles with incipient cooperation to better understand the factors driving these social traits. Specifically, I evaluate different causes of extra-pair mating in socially monogamous beetles, the potential benefits that young adult offspring may …


Spatial Genetic Structure And Local Adaptation Within And Among Foxtail Pine (Pinus Balfouriana Subsp. Balfouriana) Populations Located In The Klamath Mountains, California, Rebecca D. Piri Jan 2019

Spatial Genetic Structure And Local Adaptation Within And Among Foxtail Pine (Pinus Balfouriana Subsp. Balfouriana) Populations Located In The Klamath Mountains, California, Rebecca D. Piri

Theses and Dissertations

Foxtail pine (Pinus balfouriana) is a subalpine conifer endemic to California, notably separated into two disjunct subspecies. Previous studies have described the northern subspecies,Pinus balfouriana subsp. balfouriana,as having an uncommonly high level of genetic differentiation and no discernible spatial patterns in phenotypic variation. This study seeks to characterize the spatial genetic structure and patterns of selection of the northern subspecies (Pinus balfouriana subsp. balfouriana) using genome-wide data and to identify the influence of ecology and environment on the unique genetic patterns. I show that genetic differentiation among populations is much less than previously estimated …


The Role Of Local Adaptation On Biting Performance In Trinidadian Guppies, Hannah E. Cohen Jan 2019

The Role Of Local Adaptation On Biting Performance In Trinidadian Guppies, Hannah E. Cohen

College of Graduate Studies: Theses & Dissertations

Divergent selection pressures in populations that occupy different environments can result in phenotypic differentiation in traits that provide a local fitness advantage. Trinidadian guppy (Poecilia reticulata) populations are separated by physical barriers such as waterfalls which result in repeated shifts in selective pressures from predator avoidance in high predation environments towards resource competition in low predation environments. Such shifts in selection pressures have previously shown that a range of locally adapted morphological and behavioral traits are changed. However, the role of local adaptation on biting behaviors remains unclear. I analyzed morphological differences such as body length, jaw position, …


Multi-Locus Phylogenetic Inference Of The Howler Monkey (Alouatta) Radiation In South America., Esmeralda Ferreira Jan 2019

Multi-Locus Phylogenetic Inference Of The Howler Monkey (Alouatta) Radiation In South America., Esmeralda Ferreira

Dissertations and Theses

Abstract

Howler monkeys (Alouatta) are the most widely distributed New World primates, ranging from southern Mexico to northern Argentina. They occur in tropical rain forests, flooded and gallery forests, and deciduous and semi-deciduous environments. Despite their importance as seed dispersers, howlers have also been known to be ecological indicators. Available phylogenetic hypotheses for this genus have used chromosomal characters, morphological characteristics, and a limited number of molecular markers and specimens. In spite of these analyses, branching patterns among howler species lineages conflict between studies or remain unresolved. Using 14 unlinked non-coding intergenic nuclear regions under both a concatenated …