Ecology and Evolutionary Biology Commons^™

Intraguild Predation: Interactions Between Predators, Pathogens, And Their Shared Resources In Crop Pest Communities, Andrew Jason Flick

LSU Doctoral Dissertations

Crop pest management requires an understanding of the complex interactions among pest species that potentially damage crop yield and species that may be crucial for controlling pest species outbreaks. For example, predators, parasitoids, and pathogens are constantly interacting via their shared prey or hosts. Predators may prefer infected prey, which can be easier to catch; however, infected prey may be less nutritious or even lethal for predators. These interactions then dictate the short-term dynamics of host and pathogen as well as between prey and predator. "How these dynamics change as the species in the system change either empirically or theoretically?" …

Effects Of Soil Nitrogen On Diploid Advantage In Fireweed, Chamerion Angustifolium (Onagraceae), Alex L. Bales, Erika Hersch-Green

Department of Biological Sciences Publications

In many ecosystems, plant growth and reproduction are nitrogen limited. Current and predicted increases of global reactive nitrogen could alter the ecological and evolutionary trajectories of plant populations. Nitrogen is a major component of nucleic acids and cell structures, and it has been predicted that organisms with larger genomes should require more nitrogen for growth and reproduction and be more negatively affected by nitrogen scarcities than organisms with smaller genomes. In a greenhouse experiment, we tested this hypothesis by examining whether the amount of soil nitrogen supplied differentially influenced the performance (fitness, growth, and resource allocation strategies) of diploid and …

The New Natural Distribution Area Of Aspen (Populus Tremula L.) Marginal Populations In Pasinler In The Erzurum Province, Turkey, And Its Stand Characteristics, Halil Bariş Özel, Sezgin Ayan, Serdar Erpay, Bojan Simovski

Aspen Bibliography

Background and Purpose: Genetic diversity is the basis for adaptation and survival of tree species under changing environmental conditions, representing the key issue of stability and productivity of forest ecosystems. This paper studies the marginal population characteristics and stand dynamics of aspen tree (Populus tremula L.) in natural, pure and mixed forest stands with Scots pine (Pinus sylvestris L.). These populations were observed on founding sites between Timarli Valley and Timan Plateau located in Pasinler in the Erzurum Province in Turkey.
Materials and Methods: Three replicated sample sites were established according to a randomised block design …

Living Shoreline Stabilization To Increase Resiliency At De Soto National Memorial, Linda Walters, Melinda Donnelly, Christian Pilato, Suzanne Connor

CEELAB Research Data

De Soto National Memorial (Bradenton, FL) is an important location where both Native Americans and De Soto's army of soldiers once lived. We have been working closely with the National Park Service and the University of Central Florida to understand how to best stabilize this shoreline using living shoreline techniques combined with long-term natural recruitment. Stabilizing De Soto's shoreline is essential to decrease erosion and shoreline loss to protect the Park's cultural and natural resources, especially the numerous historically significant shell middens. Through pre-restoration monitoring, we determined that high-energy boat wakes were limiting natural mangrove recruitment. Lack of retention of …

A Change In Grain? Diet Induced Plasticity In The Generalist Grasshopper Melanoplus Differentialis, Austin M. Culotta

LSU New Orleans Theses and Dissertations

Phenotypic plasticity is favored in heterogeneous environments in which alternative phenotypes can exploit alternative resources. However, it’s not clear whether phenotypic plasticity is useful in environments that become more homogenous over an organism’s life cycle. I studied a population of grasshopper Melanoplus differentialis that experiences high resource diversity as nymphs but low resource diversity as adults to determine if individuals can undergo diet-induced morphological plasticity in head shape to increase biting ability and ingestion of hard diets. Insects on a soft diet were larger and had greater bite force than those on a hard diet. Head structures related to chewing …

Legacy Habitat Suitability Of Eastern Oysters (Crassostrea Virginica) In Louisiana: A Prelude To Mississippi River Delta Freshwater Diversions, Tasia Mv Denapolis

LSU New Orleans Theses and Dissertations

The Louisiana oyster industry is greatly impacted by freshwater and sediment diversions that are part of the effort to restore the state’s coastline. A habitat suitability index (HSI) proposes species-habitat relationships that can be instrumental in creating impact assessments and suitability predictions for management as new diversions are implemented. An oyster (Crassostrea virginica) HSI was developed using three variables crucial to oyster sustainability: average annual salinity, minimum monthly salinity, and average salinity during the spawning season. These Legacy HSI visualizations show annual fluctuations in the distribution of zones suitable for oyster cultivation prior to proposed diversions in Pontchartrain …

Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller

LSU New Orleans Theses and Dissertations

Global climate change is projected to impact multiple levels of biodiversity by imposing strong selection pressures on existing populations, triggering shifts in species distributions, and reorganizing entire communities. The Lower Guineo-Congolian region in central Africa, a reservoir for amphibian diversity, is predicted to be severely affected by future climate change through rising temperatures and greater variability in rainfall. Geospatial modelling can be used to assess how environmental variation shapes patterns of biological variation – from the genomic to the community level – and use these associations to predict patterns of biological change across space and time. The overall goal of …

Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xvii.Revision Of Neobuthus, With Description Of Seven New Species From Ethiopia, Kenya And Somaliland (Buthidae), František Kovařík, Graeme Lowe, Ahmed Ibrahim Awale, Hassan Sh Abdirahman Elmi, Ali Abdi Hurre

Euscorpius

New information about the taxonomy and distribution of the genus Neobuthus Hirst, 1911 is presented, based on material recently collected mainly from Somaliland, but also Djibouti and Kenya. Emended diagnoses are proposed for N. berberensis Hirst, 1911 and N. ferrugineus (Kraepelin, 1898) sensu stricto. New species described are: N. amoudensis sp. n. from Ethiopia and Somaliland; N. erigavoensis sp. n., N. factorio sp. n., N. gubanensis sp. n., N. maidensis sp. n., and N. montanus sp. n. from Somaliland; and N. kloppersi sp. n. from Kenya. This doubles the number of species in Neobuthus, unearthing a rich diversification …

The Evolution Of Diet Breadth In Melissodes Bees (Apidae: Eucerini), Karen W. Wright

Biology ETDs

The relationship between phytophagous insects and their host plants has interested scientists since Darwinian times. Using modern phylogenetic inference, we are able to investigate these patterns using, not only the phylogenies of the insects, but the evolutionary relationships among the plants they feed on as well. The relationships between bees and the plants they pollinate were traditionally seen as mutualistic and were treated separately from the research investigating the antagonistic relationships between phytophagous insects and their host plants. However, recent phylogenetic studies have made great progress including bee-host relationships in with the larger body of work on phytophagous insects.

The …

Revision Of The Central Asian Scorpion Genus Anomalobuthus Kraepelin, 1900, With Descriptions Of Three New Species And A Generic Synonymy (Scorpiones: Buthidae), Rolando Teruel, František Kovařík, Victor Fet

Euscorpius

We revise the Central Asian endemic genus Anomalobuthus Kraepelin, 1900, which was considered monotypic for more than 100 years until the recent addition of a second species from Iran (Teruel et al., 2014). We redefine the generic diagnosis of Anomalobuthus and reveal that it is composed of no less than six species, three of which are described as new: A. krivochatskyi, sp. n. (central Uzbekistan and extreme southern Kazakhstan), A. lowei, sp. n. (southeastern Kazakhstan), and A. pavlovskyi, sp. n. (south-central Kazakhstan and extreme northern Turkmenistan). The monotypic genus Psammobuthus Birula, 1911 (described from the Ferghana Valley …

Dependence Of Aspen Stands On A Subsurface Water Subsidy: Implications For Climate Change Impacts, D. M. Love, M. D. Venturas, J. S. Sperry, P. D. Brooks, J. L. Pettit, Y. Wang, W. R. L. Anderegg, X. Tai, D. S. Mackay

Aspen Bibliography

The reliance of 10 Utah (USA) aspen forests on direct infiltration of growing season rain versus an additional subsurface water subsidy was determined from a trait- and process-based model of stomatal control. The model simulated the relationship between water supply to the root zone versus canopy transpiration and assimilation over a growing season. Canopy flux thresholds were identified that distinguished nonstressed, stressed, and dying stands. We found growing season rain and local soil moisture were insufficient for the survival of 5 of 10 stands. Six stands required a substantial subsidy (31–80% of potential seasonal transpiration) to avoid water stress and …

Engineering Eden: The World's Attempt To Outsmart Water Scarcity, Kaitlin A. Sullivan

Capstones

Countries around the world are running out of fresh water, 43 already live with water scarcity, requiring more water than they have. In 2015 the global water crisis took first place in The World Economic Forum’s assessment of the risks that will have the most significant impact on economies, environments and people. Water beat out 27 other long-term risks including infectious diseases and weapons of mass destruction. What happened to Crowley County on the plains of Southeastern Colorado is a cautionary tale of borrowed water. It's been called the Detroit of Colorado, decimated by the reliance of a single industry. …

Ask The Beasts Of The Southern Wild: Exploring Human Identity As Beast, Being And Beholder In Ask The Beasts: Darwin And The God Of Love And Beasts Of The Southern Wild, Stephanie Cherpak Clary

Journal of Religion & Film

Anthropocentrism and hierarchical dualism together encourage a dangerous anthropology where human primacy among creation and the prioritization of certain humans leads to destruction for all. During a time when suffering caused by climate change continues to intensify, it is increasingly important to find compelling ways to share the stories of those who suffer most. I will explore how Beasts of the Southern Wild (Zeitlin, 2012) contextualizes the ecofeminist theology found in Johnson’s Ask the Beasts: Darwin and the God of Love (2014), specifically the idea of humans identifying as beasts, beings and beholders. Furthermore, I will discuss how the representation …

Microplastics In Full View: Birds As Bioindicators Of Malta's Coastal Ecosystem Health, Dalton Brauer

Masters Theses, 2010-2019

Plastic pollution has recently become a widely studied topic, yet research on microplastics has remained lacking for specific geographic regions. Microplastics are small plastics resulting from degradation or the dumping of raw material and can lead to deleterious impacts on the coastal marine environment and its organisms. To assess Malta’s coastal environmental health, water birds (inshore, offshore and pelagic species) were used as bioindicators by assessing the presence and abundance of plastic within their stomach contents. The project hoped to fill some of the current gaps in knowledge on microplastics within Malta by creating a working baseline, as well as …

Miniscule Differences Between Sex Chromosomes In The Giant Genome Of A Salamander, Melissa C. Keinath, Nataliya Y. Timoshevskaya, Vladimir A. Timoshevskiy, S. Randal Voss, Jeramiah J. Smith

Biology Faculty Publications

In the Mexican axolotl (Ambystoma mexicanum), sex is determined by a single Mendelian factor, yet its sex chromosomes do not exhibit morphological differentiation typical of many vertebrate taxa that possess a single sex-determining locus. As sex chromosomes are theorized to differentiate rapidly, species with undifferentiated sex chromosomes provide the opportunity to reconstruct early events in sex chromosome evolution. Whole genome sequencing of 48 salamanders, targeted chromosome sequencing and in situ hybridization were used to identify the homomorphic sex chromosome that carries an A. mexicanum sex-determining factor and sequences that are present only on the W chromosome. Altogether, …

Use Of Co-Immunoprecipitations And 2d Gel Electrophoresis To Identify Protein-Protein Interactions Of Maturase K, Lauren Angello

Honors Theses

Maturase K (MatK) is the only group II intron encoded protein in the chloroplast of land plants. Maturases are prokaryotic enzymes that catalyze formation of the lariat structure needed for intron removal from precursor RNAs. The chloroplast maturase MatK, is a descendant of prokaryotic maturases, however, unlike its prokaryotic relatives, MatK is thought to catalyze excision of, not only its own intron, but also the introns of other group II introns in the plastome. Similar to the multiprotein and snRNA spliceosomal complex of the nucleus, it is postulated that MatK is not working alone to excise these introns but most …

Employing Natural History Collections In The Aid Of Conservation: Streamlining An Approach To Model Species Distributions En Masse For The Preservation Of Biodiversity, Alice Fornari

Master's Projects and Capstones

Using species distribution models (SDMs) in Natural History Collections (NHCs) can influence how humans implement conservation changes in flora and fauna communities and ecosystems. Through the use of legacy data (old NHCs and their associated locality/collection information), data correction (background data or pseudo absences added to presence-only data), and the SDM software, Maxent (and its associated geographic information systems or GIS projected models), it has been shown that it is feasible to create a low budget protocol/setup to project the past, present and future of species population changes. This has been done in the past few decades as more collections …

Changing Land-Use From Pinus Elliottii To Eucalyptus Bentamii In Southwest Louisiana Affects Understory Vegetation Richness, Diversity, And Functional Diversity Patterns, Andrea De Stefano

LSU Doctoral Dissertations

In the Western Gulf region of the United States cold-tolerant eucalyptus have been explored as pulpwood feedstock. However, non-native plantations may alter understory species diversity, modifying environmental conditions and soil characteristics. Few studies have compared eucalyptus plantations with other ecosystems to understand the impacts of converting these land uses on understory vegetation in the United States. Three plantations were selected: (1) slash pine (Pinus elliottii) established in 2008, (2) slash pine established in 2013, and (3) and Camden white gum (Eucalyptus benthamii) established in 2013. The objectives of this study were to: (1) investigate potential changes …

Understory Community Assembly Following Wildfire In Boreal Forests: Shift From Stochasticity To Competitive Exclusion And Environmental Filtering, Bo Liu, Han Y. H. Chen, Jian Yang

Forestry and Natural Resources Faculty Publications

Understory vegetation accounts for the majority of plant species diversity and serves as a driver of overstory succession and nutrient cycling in boreal forest ecosystems. However, investigations of the underlying assembly processes of understory vegetation associated with stand development following a wildfire disturbance are rare, particularly in Eurasian boreal forests. In this study, we measured the phylogenetic and functional diversity and trait dispersions of understory communities and tested how these patterns changed with stand age in the Great Xing'an Mountains of Northeastern China. Contrary to our expectation, we found that understory functional traits were phylogenetically convergent. We found that random …

Parental Habituation To Human Disturbance Over Time Reduces Fear Of Humans In Coyote Offspring, Christopher J. Schell, Julie K. Young, Elizabeth V. Lonsdorf, Rachel M. Santymire, Jill M. Mateo

Wildland Resources Faculty Publications

A fundamental tenet of maternal effects assumes that maternal variance over time should have discordant consequences for offspring traits across litters. Yet, seldom are parents observed across multiple reproductive bouts, with few studies consider‐ ing anthropogenic disturbances as an ecological driver of maternal effects. We ob‐ served captive coyote (Canis latrans) pairs over two successive litters to determine whether among‐litter differences in behavior (i.e., risk‐taking) and hormones (i.e., cortisol and testosterone) corresponded with parental plasticity in habituation. Thus, we explicitly test the hypothesis that accumulating experiences of anthropogenic disturbance reduces parental fear across reproductive bouts, which should have disparate phenotypic …

Phylogeographic Analyses Of A Widely Distributed Populus Davidiana: Further Evidence For The Existence Of Glacial Refugia Of Cool‐Temperate Deciduous Trees In Northern East Asia, Zhe Hou, Zhaoshan Wang, Zhanyang Ye, Shuhui Du, Shuya Liu, Jianguo Zhang

Aspen Bibliography

Despite several phylogeographic studies had provided evidence to support the existence of glacial refugia of cool‐temperate deciduous trees in northeast China, the species used in these studies were limited by the species ranges, which could not exclude the possibility that northern populations were the colonists from southern refugial populations during the last glacial maximum (LGM). Here, we estimated the nucleotide variation in Populus davidiana, a widespread species distributed in Eurasia. Three groups in northeast, central, and southwest China were constructed according to the simulation results from SAMOVA, composition of chloroplast haplotypes and structure results. We revealed that the northeast …

Occurrence Of Alkaloids In Grass Seeds Symbiotic With Vertically-Transmitted Epichloë Fungal Endophytes And Its Relationship With Antioxidants, Pedro E. Gundel, Charlotte E. Seal, Fernando Biganzoli, Marco A. Molina-Montenegro, Beatriz R. Vázquez-De-Aldana, Iñigo Zabalgogeazcoa, Lowell P. Bush, María A. Martínez-Ghersa, Claudio M. Ghersa

Plant and Soil Sciences Faculty Publications

Host organisms can acquire new functional traits through symbiosis. Seed-transmitted Epichloë fungal endophytes are known to protect host plants against herbivores and increase tolerance to abiotic stresses by alkaloids and antioxidants, respectively (currencies of mutualism). Whereas, alkaloids are fungal products with demonstrated effects at plant vegetative stage, few studies have focused on alkaloids in seeds. We assessed the occurrence of fungal alkaloids and determined their concentrations in seeds of two host grasses, Festuca rubra and Lolium multiflorum. Then, we sought for a relationship with the antioxidants tocochromanols and glutathione, which are involved in the control of oxidative stress. Different …

Accumulation And Transmission Dynamics Of A Naturally-Occurring Mtdna Deletion In Caenorhabditis Briggsae, Jennifer Anne Sullins

Dissertations and Theses

Maintaining mitochondrial genome sequence integrity is essential for preserving normal mitochondrial function. Several human diseases have been associated with heteroplasmic mitochondrial genome mutations, but few genetic systems can simultaneously represent pathogenic mitochondrial genome evolution and inheritance. The nematode Caenorhabditis briggsae is one such model. Natural C. briggsae isolates are globally-distributed and phylogenetically grouped into three distinct clades, with isolates exhibiting varying levels of a large-scale mtDNA deletion, nad5∆. Furthermore, a small subset of clade II isolates exhibits putative compensatory mutations that may reduce the risk of deletion formation and accumulation in those populations. In this thesis, the author characterizes the …

Web Based Mapping Applications Evs 510, Michael Cerbo

Library Impact Statements

No abstract provided.

Natural Resource Data Analysis Evs 515, Michael Cerbo

Library Impact Statements

No abstract provided.

Natural Resource Data Management Visualization Evs 514, Michael Cerbo

Library Impact Statements

No abstract provided.

Web Based Mapping Lab Evs 511, Michael Cerbo

Library Impact Statements

No abstract provided.

Sustainable Natural Resource Management Evs 518, Michael Cerbo

Library Impact Statements

No abstract provided.

Natural Resource Management Planning Evs 519, Michael Cerbo

Library Impact Statements

No abstract provided.

The Genomic Landscape Of Molecular Responses To Natural Drought Stress In Panicum Hallii., John T. Lovell, Jerry Jenkins, David B. Lowry, Sujan Mamidi, Avinash Sreedasyam, Xiaoyu Weng, Kerrie Barry, Jason Bonnette, Brandon Campitelli, Chris Daum, Sean P. Gordon, Billie A. Gould, Albina Khasanova, Anna Lipzen, Alice Macqueen, Juan Diego Palacio-Mejía, Christopher Plott, Eugene V. Shakirov, Shengqiang Shu, Yuko Yoshinaga, Matt Zane, Dave Kudrna, Jason D. Talag, Daniel Rokhsar, Jane Grimwood, Jeremy Schmutz, Thomas E. Juenger

Biological Sciences Faculty Research

Environmental stress is a major driver of ecological community dynamics and agricultural productivity. This is especially true for soil water availability, because drought is the greatest abiotic inhibitor of worldwide crop yields. Here, we test the genetic basis of drought responses in the genetic model for C4 perennial grasses, Panicum hallii, through population genomics, field-scale gene-expression (eQTL) analysis, and comparison of two complete genomes. While gene expression networks are dominated by local cis-regulatory elements, we observe three genomic hotspots of unlinked trans-regulatory loci. These regulatory hubs are four times more drought responsive than the genome-wide average. Additionally, cis- and trans-regulatory …