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Full-Text Articles in Life Sciences

The Community Ecology Of Ants On The Cumberland Plateau And A Taxonomic Redescription Of The Genus Stenamma Westwood, 1839 (Hymenoptera: Formicidae: Myrmicinae) In A Southeastern Treatment, Zachary Brown Aug 2023

The Community Ecology Of Ants On The Cumberland Plateau And A Taxonomic Redescription Of The Genus Stenamma Westwood, 1839 (Hymenoptera: Formicidae: Myrmicinae) In A Southeastern Treatment, Zachary Brown

Theses and Dissertations

Grassland communities represent major biodiversity hotspots across the United States. Among these grassland types is the short-leaf pine savanna, a major historical habitat along the Cumberland Plateau. The Cumberland Plateau’s grasslands are under threat due to land use changes such as urbanization and land conversion to pasture and hardwood forests. This study seeks to better understand the community ecology of ants on the Cumberland Plateau using powerlines as a comparison to degraded and historic habitats. Ants have a preference between open sites and forested sites, a separation of 44.5% on a DCA. The Simpson diversity places the short-leaf pine savanna …


Diversity And Distribution Of Bryozoans Of The Northern To Central Rocky Outer Coast Of California, Ismael Chowdhury Jan 2023

Diversity And Distribution Of Bryozoans Of The Northern To Central Rocky Outer Coast Of California, Ismael Chowdhury

Cal Poly Humboldt theses and projects

The phylum Bryozoa is one of the most diverse groups of marine invertebrates, with a global distribution that spans marine and fresh waters. This study analyzes the Bryozoa in infralittoral communities on rocky surfaces from northern California (Point Saint George) to central California (Estero Bay), spanning 940 kilometers and encompassing 12 rocky intertidal sites. Although recent studies on bryozoan taxonomy and phylogeny have increased due to scanning electron microscopy (SEM) and high throughput sequencing, there is still a lack of studies on species found in shallow waters at intertidal depths, particularly in the northeastern Pacific. This study aims to expand …


Taxonomic Resolution Assessment And Biodiversity Evaluations For Deep-Sea Fish Assemblages In A Pelagic Ecosystem Of The Northern Gulf Of Mexico, Krista N. Scheuerman Aug 2022

Taxonomic Resolution Assessment And Biodiversity Evaluations For Deep-Sea Fish Assemblages In A Pelagic Ecosystem Of The Northern Gulf Of Mexico, Krista N. Scheuerman

All HCAS Student Capstones, Theses, and Dissertations

Knowledge of community assemblages and biodiversity is important for monitoring health and resilience in an ecosystem. Taxonomic and functional biodiversity of mesopelagic (200- 1000 m) fishes is extremely rich in the Gulf of Mexico. The aim of this study was to compare calculations of biodiversity and community structures at varying taxonomic resolutions for deep pelagic fishes to inform future decisions about deep-sea ecosystem monitoring. This study analyzed biodiversity and assemblage structure patterns from a biological inventory of deep-sea fishes collected with a large mesh, commercial-sized, high-speed rope trawl in the Gulf of Mexico between June 21st and July 14 …


A Systematic And Biogeographic Study Of Trillium (Melanthiaceae), Jayne A. Lampley Dec 2021

A Systematic And Biogeographic Study Of Trillium (Melanthiaceae), Jayne A. Lampley

Doctoral Dissertations

Trillium (Melanthiaceae, Parideae) has a disjunct distribution occurring in eastern and western North America, and eastern Asia. Past studies have examined the phylogeny and historical biogeography of Melanthiaceae and Parideae, however these studies either did not fully examine these aspects within Trillium or did not employ sufficiently broad taxonomic or character sampling to clarify relationships among taxa. The first phylogenetic analysis presented in this study provides a resolved phylogeny for Trillium s.l. and Paris s.l. by using a dataset of 70 plastid coding genes and by sampling broadly from Trillium s.s., Pseudotrillium, Trillidium, Paris s.s., Daiswa, and Kinugasa. The results …


Construction Of Dichotomous Taxonomic Keys For San Francisco Bay Planktonic Diatoms, Ria Angelica Laxa May 2021

Construction Of Dichotomous Taxonomic Keys For San Francisco Bay Planktonic Diatoms, Ria Angelica Laxa

Undergraduate Honors Theses

Planktonic diatoms exhibit high biodiversity in marine systems and make a significant contribution to water column primary productivity. This makes research on planktonic diatoms particularly important in measuring the health of coastal marine ecosystems. At the University of San Francisco (USF), undergraduate research has been conducted since September 2015 to study planktonic diatoms in San Francisco Bay. A previous study by Keith (2018), Planktonic Diatom Species Succession in San Francisco Bay, documented changes in species diversity over time, observing seasonal patterns in species richness as well as the effect of environmental factors such as salinity, temperature, and rainfall on species …


More Than Meets The Eye: A Taxonomic Revision Of The Nearctic Species In The Eye-Gnat Genus Amiota Loew (Diptera: Drosophilidae), Lance E. Jones Jan 2020

More Than Meets The Eye: A Taxonomic Revision Of The Nearctic Species In The Eye-Gnat Genus Amiota Loew (Diptera: Drosophilidae), Lance E. Jones

Dissertations and Theses

Thorough biotic inventories are still needed even in families as seemingly well-studied as fruit flies (Diptera: Drosophilidae). Drosophilidae have had an outsize effect on the history of biology because of their pivotal role in the study of genetics, development, and evolution. Even with more than a century of intensive study, large gaps remain in our understanding of diversity in this fly family, including well-studied areas such as North America. This thesis presents a taxonomic revision of the Nearctic species of the genus Amiota Loew. Twenty-three species are identified as being new to science for publication at a later date. This …


Systematics Of Amanita (Amanitaceae, Agaricales, Basidiomycota) From The Guiana Shield And Central Africa, Kennan S. Mighell Jan 2020

Systematics Of Amanita (Amanitaceae, Agaricales, Basidiomycota) From The Guiana Shield And Central Africa, Kennan S. Mighell

Cal Poly Humboldt theses and projects

This study is a systematic assessment of ten species of ectomycorrhizal fungi of the genus Amanita (Amanitaceae, Agaricales, Basidiomycota) from the lowland tropical rainforests of the Guiana Shield and Central Africa. Fungi were collected in each of the above regions, analyzed morphologically, and compared to the literature on Amanita diversity worldwide. All species addressed herein are given full formal taxonomic descriptions including complete macro- and microscopic character profiles, habit, habitat, and distribution. Phylogenetic assessments using ribosomal DNA and protein coding genes are provided for Guiana Shield taxa, and sequence data for two non-protein coding regions, the …


Systematics Of Carex Section Laxiflorae (Cyperaceae), Jenna Dorey Sep 2019

Systematics Of Carex Section Laxiflorae (Cyperaceae), Jenna Dorey

Dissertations, Theses, and Capstone Projects

Carex, with more than 2100 species, is the most species-rich genus of flowering plants in temperate regions of the world. Members of the family Cyperaceae are colloquially known as sedges, and members of the genus Carex are called “true sedges.” Carex occur on every continent except for Antarctica, they thrive in a panoply of habitats, and are ecologically important as a forage source for wildlife, carbon sequestration, prevention of soil erosion, and providing habitat for fresh water invertebrates. Despite their importance many sedges are still poorly known, such as the woodland sedges in Carex section Laxiflorae, which is …


Dna Barcoding As A Tool For Species Discovery And Documentation In The Superfamily Ichneumonoidea, Sarah Meierotto Jan 2018

Dna Barcoding As A Tool For Species Discovery And Documentation In The Superfamily Ichneumonoidea, Sarah Meierotto

Theses and Dissertations--Entomology

Changes to traditional taxonomic methods to incorporate new technologies and methods have already improved the quality of species hypotheses, but more work can be done to improve the speed of new species documentation. The mitochondrial COI DNA barcode has been successfully used to identify species with high accuracy since the early 2000s, and has been used in conjunction with morphological examinations and other DNA markers to discover and delimit new species. This thesis explores the application of DNA barcodes as the primary data for delimitation and diagnosis of new species of ichneumonoids.

The genera Zelomorpha and Hemichoma are revised and …


Systematics And Biogeography Of The Cortinarius Violaceus Group And Sequestrate Evolution In Cortinarius (Agaricales), Emma Harrower Dec 2017

Systematics And Biogeography Of The Cortinarius Violaceus Group And Sequestrate Evolution In Cortinarius (Agaricales), Emma Harrower

Doctoral Dissertations

Phylogenetics is a powerful tool used for illuminating the diversity of life on Earth, their evolution and their ecology. I created a multi-gene phylogenetic tree of Cortinarius section Cortinarius and uncovered five previously overlooked species, increasing the number of species in the section from seven to twelve. All members of the clade possess both cheilocystidia and pleurocystidia and possess a pigment known as (R)-39,49-dihydroxybphenylalanine. Ancestral state reconstruction estimated that the ancestral host was most likely an angiosperm, switching hosts when encountering novel host species in new lands, and only C. violaceus associating with the Pinaceae in North America. Biogeographic analysis …


The Bee Fauna Of The Horse Mountain And Grouse Mountain Region, Humboldt County, California, Carrie Lopez Jan 2017

The Bee Fauna Of The Horse Mountain And Grouse Mountain Region, Humboldt County, California, Carrie Lopez

Cal Poly Humboldt theses and projects

Recent concerns about the ecological well-being of bee communities in California and elsewhere have increased the need for monitoring programs and studies that evaluate the impact of habitat loss and alteration on bee diversity and abundance. Such studies depend critically on the expertise of people trained in taxonomy, but their numbers have declined in recent years. My primary goal was to gain a comprehensive first-hand experience with bee identification by documenting the fauna of a previously unstudied area in the mountains of northwestern California and by writing an identification key, intended for dedicated non-specialists, to the area’s 35 species of …


Phylogeny, Systematics And Biogeography Of Short-Tailed Opossums (Didelphidae: Monodelphis), Silvia E. Pavan Sep 2016

Phylogeny, Systematics And Biogeography Of Short-Tailed Opossums (Didelphidae: Monodelphis), Silvia E. Pavan

Dissertations, Theses, and Capstone Projects

Short-tailed opossums (genus Monodelphis) comprise the most species-rich genus of New World marsupials, with 25 currently recognized species. Monodelphis comprise small, terrestrial species collectively widespread in South America, which makes the group potentially informative about biogeographic processes that have shaped the continental fauna. The genus exhibits striking variation in several phenotypic characters, notably pelage coloration, behavior, and reproductive strategies. This diversity is unique among Neotropical marsupials, and makes the group particularly interesting to investigate the evolution and the adaptive significance of phenotypic trait variation. Despite this potential, missing knowledge on phylogeny and basic taxonomy precludes broader studies on evolution …


Evolution And Phylogeny Of The Parasitoid Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke Aug 2015

Evolution And Phylogeny Of The Parasitoid Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke

Doctoral Dissertations

The first molecular phylogenetic analysis of the agriculturally important parasitoid subfamily Phasiinae (Diptera: Tachinidae) is presented, estimated from 128 worldwide taxa (80 genera) and approximately 7.6 kilobases of nuclear data. Special emphasis is placed on taxa with controversial taxonomic placement. The resultant phylogenetic tree is used to reconstruct ancestral character states, trace the evolution of significant adaptive traits within the Tachinidae, and test hypotheses about the classification of Phasiinae. Subfamily placements of the taxa Eutherini, Epigrimyiini, Litophasia, Strongygastrini, and Parerigonini are confidently resolved, the former three within Dexiinae and the latter two within Phasiinae. Due to sparse molecular evidence, …


A Taxonomic Revision Of The New World Hypoponera Santschi, 1938 (Hymenoptera: Formicidae), Shawn Thomas Dash Jan 2011

A Taxonomic Revision Of The New World Hypoponera Santschi, 1938 (Hymenoptera: Formicidae), Shawn Thomas Dash

Open Access Theses & Dissertations

The New World taxa of the pantropic ant genus Hypoponera (Ponerinae: Ponerini) is revised for the first time. The 55 previously recognized taxa have been evaluated using morphological and, when possible, ecological and biogeographical data to resolve taxon validity and species limits. Currently I recognize 42 species of Hypoponera , a number of which are new. I propose the following taxonomic outline: Hypoponera agilis (Borgmeier), Hypoponera aliena (F. Smith), Hypoponera antoniensis (Forel) stat. nov., Hypoponera apateae sp. nov., Hypoponera capilosa sp. nov., Hypoponera clinei sp. nov., Hypoponera clavatula (Emery) [= fiebrigi (Forel) syn. nov., = neglecta (Santschi) syn. nov.], Hypoponera …