Life Sciences Commons^™

Characterizing New Plant Fossils With Woody Growth From The Battery Point Formation Of Quebec (Canada), Emma T. Casselman

Cal Poly Humboldt theses and projects

The oldest woody growth has been recognized in several Early Devonian (ca. 410-395 Ma) euphyllophytes. Their taxonomic diversity is difficult to evaluate due to a lack of quantitative methods for comparing plants based on secondary xylem anatomy. In turn, this hinders understanding of their implications for the evolution of plant development. To develop metrics that quantify secondary xylem anatomy and allow for conclusive comparisons, I investigated extant taxa and Early Devonian fossil woody taxa. I developed multiple metrics for quantifying tracheid size as a function of position in the secondary xylem and tested them on a dataset of extant gymnosperms. …

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 …

Phylogenetics And Integrative Taxonomy Of African Water Snakes (Squamata: Colubridae: Grayia), Teslin Chaney

Open Access Theses & Dissertations

Grayia is a genus of relatively large (1.5 - 2.5 m) aquatic Afrotropical snakes. Recent molecular phylogenies recovered Grayia in its own distinct subfamily (Grayiinae), which was strongly supported as the sister group to Colubrinae. Because tropical African snakes are generally understudied, the relationships within Grayia are poorly known. Due to high degrees of intra- and interspecies variation, identification is often difficult and previous studies involving Grayia included misidentified specimens in other genera. The goal of this study is to create a phylogenetic tree that can be used to understand the relationships and taxonomy of Grayia via an integrative taxonomic …

A Biodiversity Survey Of The Soil Crusts Of The Geographically Isolated San Nicholas Island, California, Usa And Description Of Species In Three Genera (Atlanticothix, Pycnacronema, Konicacronema) Previously Restricted To Brazil Using A Polyphasic Approach To Cyanobacterial Taxonomy, Brian Jusko

Masters Theses

San Nicholas Island, California, USA is a geographically-isolated island that experiences a semiarid climate and exhibits significant topographic and geologic diversity. Access to the island is restricted to the public and, as a result, only one previous study has been done on the algal biodiversity of its biological soil crusts. The previous study used morphology as the sole basis of species identification, and it was the aim of this study to corroborate and expand upon the results by including molecular data. Using 16S rRNA and 16S–23S ITS sequences and phylogenetic analyses, a diverse set of taxa were identified and are …

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 Revision And Morphometric Analysis Of Selected Anthurium (Araceae) Species From Bolivia And Peru, Daniel M. Tarazona Ocana

Theses

The genus Anthurium (Araceae) consists of around 1,200 species distributed in the Neotropics, particularly in Central and South America. The montane forests in the eastern flank of the Andes, ranging from northern Ecuador to central Bolivia; hereafter, the East Andes Gradient region, are particularly rich in terms of species diversity, and include an understudied group of Anthurium species endemic to the region. Within this group of species, some taxa are difficult to distinguish from each other mainly due to the lack of identification keys, incomplete species descriptions and unknown synonyms. In this study, a combination of traditional taxonomic techniques and …

The Ecology And Evolution Of Species Rarity In Oaks (Quercus Spp.), Yingtong Wu

Dissertations

Rare species are susceptible to extinction due to ecological and genetic factors. Understanding the distribution, ecology, and evolution of rare species can provide useful information for effective conservation. To investigate species rarity, this dissertation focuses on a species-rich and ecologically diverse genus, Quercus (oaks). In Chapter 1, I aimed to understand how interactions between hosts and soil microbes contribute to habitat restriction in oak species. I performed a soil inoculum experiment on two pairs of sister oak species that show habitat divergence. I found that host-specific soil microbes contribute to habitat divergence and exclusion among sister species of oaks, but …

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 21^st and July 14 …

A Comprehensive Phylogeny Of Stick And Leaf Insects (Insecta: Phasmatodea) Reveals Widespread Taxonomic Incongruence, Jackson B. Linde

Theses and Dissertations

Stick and leaf insects (Insecta: Phasmatodea) are a mesodiverse order of insects distributed across the world. These masters of masquerade crypsis are riddled with analogous morphological characters and lack a robust taxonomic framework. It seems that convergent evolution and the re-evolution of complex traits like wings and ocelli is perhaps the rule rather than the exception in stick insects. To investigate the re-acquisition of traits in this unique study system, a robust phylogenetic framework is essential. Our analyses combine traditional Sanger data with a transcriptomic backbone to provide the most corroborated phylogenetic analyses to date. To accomplish this, we employ …

Assessing The Utility Of The Pmm And Mmc Indices Among Extant Hominoid Genera, Julie A. Strain

Theses and Dissertations

This thesis set out to incorporate extant hominoid genera into an analysis of PMM and MMC to assess utility in phylogeny and predicting known taxonomic groups. Based on previous claims, we expect PMM/pmm and MMC/mmc to perform better than M1/m1 shape and size, our baseline for success, but they do not.

Taxonomic And Phylogenetic Diversity Of Pitcher Plant Bogs In Georgia's Coastal Plain, Melanie Flood

Theses and Dissertations

Diversity studies via floristic survey and taxonomic metrics have proven essential for discerning community composition and biodiversity, however, phylogenetic analyses are necessary to reveal underlying evolutionary change and potential community assembly patterns. Pitcher plant bogs are highly diverse, highly understudied habitats that contain numerous listed and at-risk plant and animal species of Georgia.

In this study I investigated the taxonomic and phylogenetic diversity of pitcher plant bogs by asking the following questions:

1) What is the taxonomic diversity of pitcher plant bogs,

2) What is the dispersion of phylogenetic diversity within bog habitats, and

3) Does taxonomic and phylogenetic diversity …

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 …

Applications Of And Algorithms For Genome Assembly And Genomic Analyses With An Emphasis On Marine Teleosts, Brandon D. Pickett

Theses and Dissertations

The burgeoning frequency of genome sequencing in recent years is a testament to both the improvements in sequencing technologies and the utility of genomic analyses for biological discovery. The rapid proliferation in technological advancements and availability of complementary data types and techniques has obfuscated the optimal process of genome assembly and raised the barrier to entry to unprecedented levels. In this dissertation, we describe the genome assemblies performed for several marine teleosts and discuss the algorithms and applications required for genome assembly, including some of our specific contributions to the genome assembly and annotation space. In Chapter 1 and Chapter …

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

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

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 …

A Generic Classification Of The Thelypteridaceae, Susan E. Fawcett

Graduate College Dissertations and Theses

The Thelypteridaceae is among the largest fern families, with over 1000 species, and comprises about 10% of all fern diversity. The family is cosmopolitan and most diverse near the equator, although species range as far north as Greenland and Alaska, and as far south as southern New Zealand. The generic classification of the Thelypteridaceae has been the subject of much controversy among authors. Proposed taxonomic systems have varied from recognizing more than 1000 species in the family within a single genus, Thelypteris, to systems favoring upwards of 30 genera. Insights on intrafamilial relationships have been gained from recent phylogenetic studies, …

Vines In The Neotropics: Phylogenomics, Biogeography And Systematics In Passion Flowers (Passiflora Subgenus Decaloba Section Decaloba), Serena Acha

Dissertations

With 600 species, Passiflora is a large, morphologically complex and broadly distributed genus in Passifloraceae that represents a major challenge to scientists interested in understanding the evolutionary history of tropical vines. Passiflora has been divided into subgenera, super sections and sections. One of the most enigmatic and species-rich (~120 spp.) groups in Passiflora is section Decaloba, which occurs in the Neotropics and is particularly diverse in Andean montane forests. In this study, we used phylogenomic and population genomic approaches to investigate the evolutionary history, biologeography, species boundaries, and taxonomy of Passiflora section Decaloba. We sampled herbarium specimens, extracted …

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 …

Taxonomy And The History Of Science: A Critical Analysis Of Four Historic Publications, Christopher M. Rogers

KSU Journey Honors College Capstones and Theses

The history of taxonomy is not usually taught in modern biology classes, but it is necessary to understand the history of classification and science as a whole in order to better understand the processes of classification and thinking that are commonly taught at the college level. Through the exploration of the difficulties of publishing, Linnaeus' Species Plantarum, and three pre-Linnaean works from Pliny the Elder, Nehemiah Grew, and Rembert Dodoens, I have found that the history of the sciences has been largely distorted. The distortion appears to be of many factors, including the replacement of ideas, censorship from scholarly …

Morphological And Color Variation In Poicephalus Parrots, Eileen Connon

Undergraduate Honors Thesis Projects

Though describing and delimiting species is one of the principle aspects of many disciplines within biology, there is often debate about which methods and concepts should be used to make such decisions. The Tobias criteria for quantitative species delimitation represent one attempt to create a standard method of delimiting species based on the morphological species concept. However, previous examples of using these criteria have not always been completely quantitative. This study uses quantitative morphological and color data of three Poicephalusparrots as a case study for the effectiveness of the Tobias criteria. The results show varying levels of support for …

Diversity And Evolution Of Seeds In Cuscuta (Dodders, Convolvulaceae): Morphology And Structure, Magdalena Olszewski

Theses and Dissertations (Comprehensive)

Cuscuta is a genus of nearly 200 obligate stem parasites with a nearly cosmopolitan distribution and considerable agricultural and ecological significance. Dodder seeds are considered “unspecialized”, with no morphological adaptations towards particular dispersal vectors; however, the seed coat anatomy has recently suggested an adaptation to endozoochory. This is the first attempt to provide a genus-wide overview of the diversity in morphology and anatomy of Cuscuta seeds, together with an assessment of the water gap and exploration of various form-function relationships. I surveyed 104 species belonging to all four Cuscuta subgenera. Seeds of the species of the first infrageneric dodder …

Revision Of The Genus Monatractides (Parasitengona, Torrenticolidae) Of The United States And Canada: New Species, Re-Descriptions, Phylogenetics, And A Key To Species, Whitney Anne Nelson

Graduate Theses and Dissertations

The full suite of known Monatractides (Parasitengona, Torrenticolidae) taxa of North America (north of Mexico) are investigated herein using integrative methods. Species hypotheses are supported with morphology, geography, and phylogenetic analysis of the barcoding region of COI for 154 individuals from over 100 localities. Relationships between species are examined with a combined analysis of COI and 28S rDNA for 55 specimens. Previously described species are examined and re-described with color images and updated information, where possible. Our results indicate the need to synonymize two species: M. californica (Marshall, 1943) is a junior synonym of M. geographica (Marshall, 1943). We describe …

Historical Biogeography And Natural History Of Nocturnal Wasps In The Southwestern Deserts With Special Emphasis On The Genus Chyphotes (Hymenoptera: Chyphotidae), Emily A. Sadler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Deserts are interesting places due to the large number of plants and animals that live there. Nocturnal wasps are extremely abundant in deserts, but they are difficult to identify and their life cycles are not well known especially the families of Chyphotidae, Tiphiidae (Brachycistidinae), and Mutillidae (velvet ants). In this dissertation, I determine how to correctly identify a particularly difficult group of species that all have black heads from the family Chyphotidae. This is important because these species make up a large proportion of specimens collected. Also, I expanded our knowledge on the distribution of the species of these three …

Evaluation Of The Phylogenetic Relationships Of The Marine Rivulariaceae., Jose Alberto Martinez Yerena

Masters Theses

Historically, the Rivulariaceae family has grouped all heteropolar, tapered and heterocitous Cyanobacteria, however recent description of multiple cyanobacterial populations with this morphotype using 16S rRNA phylogenies have reported that the populations with this morphotype are polyphyletic, and many new and old tapered and heteropolar genera (Cyanomargarita, Gloeothrichia, Rohoaltiella, etc.) have been classified and reclassified to different families than the Rivulariaceae. This is also the case of the main genera of the family (Rivularia and Calothrix), which have been repeatedly reported as polyphyletic, and whose separation to different families has been called for. In this project I carried out the evaluation …

A Review Of The Serica (Coleoptera: Scarabaeidae: Melolonthinae) Of Mexico, Canada, And The Western United States, Reese John Worthington

Electronic Theses and Dissertations

Twenty-two species and subspecies of Serica occur in Mexico. Serica ensenada Saylor, 1948 is recognized as a junior synonym of Serica pilifera Horn, 1894. Two new species, Serica ascia Lago & Worthington and Serica fenestra Lago & Worthington are described from Mexico. Three genera of Sericini are recorded from Canada, Maladera castanea (Arrow), Nipponoserica peregrina (Chapin), and twelve species of Serica. Seventy-seven species and subspecies of Serica occur in the contiguous United States west of the 100th meridian. Eleven new species, Serica berriani Lago & Worthington, Serica cuneiverpa Lago & Worthington, Serica desolaterra Lago & Worthington, Serica katelinae Lago & …

Identification Of Taxonomic And Functional Ichthyofaunal Zones Within The James River Basin, Virginia, Joseph L. Noel

Theses and Dissertations

Environmental gradients structure ichthyofaunal communities longitudinally along river networks via the selective filtering of species’ traits. In many instances, these environmental influences have created distinct zones of co-occurring fish species. Zonation studies have most often been conducted with taxonomic data (species x site matrices), but the increasing availability of functional trait data creates an opportunity to build more rigorous understanding of species’ co-occurrence patterns. Notably, zonation studies that use taxonomic data may not reveal the same patterns as studies based on trait data. In this study, we tested for distinct ichthyofaunal zonation in James River Basin, VA using a combination …

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

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 Biogeography And Nesting Biology Of Anthophora, With A Revision And Phylogeny Of The Anthophora (Micranthophora), Michael C. Orr

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bees are necessary pollinators for a vast array of different plants, including many which we rely on for food. In order to grow sufficient crops to feed the world’s growing population, we need to make sure our crops are visited by the most effective possible pollinators. However, this is complicated by the fact that there are over 4,000 bee species in North America, many of which vary in their pollination effectiveness and are difficult to identify. My dissertation’s first two data chapters focus on classifying the species of the xeric solitary bee group Anthophora subgenus Micranthophora, including seven newly …