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Articles 181 - 210 of 553

Full-Text Articles in Biology

Byu Undergraduates Explore The Flipped Classroom In Search Of The Best Pedagogy For Introductory Biology, Jamie Jensen Mar 2016

Byu Undergraduates Explore The Flipped Classroom In Search Of The Best Pedagogy For Introductory Biology, Jamie Jensen

Journal of Undergraduate Research

This report will outline how effectively we met our academic and mentoring objectives.I have listed below both the academic and mentoring objectives put forth in the original proposal and have outlined how they were met or modified over the course of the past two years.

Academic Objective: To test two hypotheses about the causal mechanisms behind the flipped classroom.


2013-2014 Final Report : Ephedra (Each Person Has Essential Disciplinary Research Abilities) In Interdisciplinary Climate Change Studies, Richard Gill Mar 2016

2013-2014 Final Report : Ephedra (Each Person Has Essential Disciplinary Research Abilities) In Interdisciplinary Climate Change Studies, Richard Gill

Journal of Undergraduate Research

The central aim of this proposal was to provide opportunities for students from diverse academic backgrounds to work collaboratively on a number of federally funded projects that include Colorado Plateau grasslands, the Mojave Desert, the Great Basin sagebrush steppe, and the Uintah Mountains. This proposal funded a portion of the salary for 9 students from life sciences, and engineering. The mentoring environment and plan focused on allowing students with diverse interests and training to work together on complex problems with frequent interaction with faculty and graduate students. We have a novel undergraduate lab that integrates training in science across the …


Does Habitat Restoration Increase Coexistence Of Native Stream Fishes With Introduced Brown Trout: A Case Study On The Middle Provo River, Utah, Usa, Mark C. Belk, Eric J. Billman, Craig Ellsworth, Brock R. Mcmillan Mar 2016

Does Habitat Restoration Increase Coexistence Of Native Stream Fishes With Introduced Brown Trout: A Case Study On The Middle Provo River, Utah, Usa, Mark C. Belk, Eric J. Billman, Craig Ellsworth, Brock R. Mcmillan

Faculty Publications

Restoration of altered or degraded habitats is often a key component in the conservation plan of native aquatic species, but introduced species may influence the response of the native community to restoration. Recent habitat restoration of the middle section of the Provo River in central Utah, USA, provided an opportunity to evaluate the effect of habitat restoration on the native fish community in a system with an introduced, dominant predator—brown trout (Salmo trutta). To determine the change in distribution of fish species and community composition, we surveyed 200 m of each of the four study reaches both before …


Integrative Analyses Reveal Signaling Pathways Underlying Familial Breast Cancer Susceptibility, Stephen R. Piccolo, Laura M. Hoffman, Thomas Conner, Gajendra Shrestha, Adam L. Cohen, Jeffrey R. Marks, Leigh A. Neumayer, Cori A. Agarwal, Mary C. Beckerle, Irene L. Andrulis, Avrum E. Spira, Philip J. Moos, Saundra S. Buys, William Evan Johnson, Andrea H. Bild Mar 2016

Integrative Analyses Reveal Signaling Pathways Underlying Familial Breast Cancer Susceptibility, Stephen R. Piccolo, Laura M. Hoffman, Thomas Conner, Gajendra Shrestha, Adam L. Cohen, Jeffrey R. Marks, Leigh A. Neumayer, Cori A. Agarwal, Mary C. Beckerle, Irene L. Andrulis, Avrum E. Spira, Philip J. Moos, Saundra S. Buys, William Evan Johnson, Andrea H. Bild

Faculty Publications

The signaling events that drive familial breast cancer (FBC) risk remain poorly understood. While the majority of genomic studies have focused on genetic risk variants, known risk variants account for at most 30% of FBC cases. Considering that multiple genes may influence FBC risk, we hypothesized that a pathway‐based strategy examining different data types from multiple tissues could elucidate the biological basis for FBC. In this study, we performed integrated analyses of gene expression and exome‐sequencing data from peripheral blood mononuclear cells and showed that cell adhesion pathways are significantly and consistently dysregulated in women who develop FBC. The dysregulation …


Phylogenetic Relationships Of Cottids (Pisces: Cottidae) In Upper Snake River Basin Of Western North America, Sun Yeong Oh Mar 2016

Phylogenetic Relationships Of Cottids (Pisces: Cottidae) In Upper Snake River Basin Of Western North America, Sun Yeong Oh

Theses and Dissertations

Freshwater sculpins (Cottus) are common throughout temperate regions of the Northern Hemisphere. Their broad distribution in the Western North America makes them a good model for understanding phylogeographic relationships among western fishes. Within much of the interior west three lineages, C. bairdii, C. confusus, and the C. beldingii complex, are most prevalent. The distribution of these three overlap in the Snake River Basin. All occur below Shoshone Falls on the Snake River. However, only two currently reside in the Upper Snake River above the falls. An exception are the Lost River streams of central Idaho. While …


Ab Blood Type And Its Genetic Relationship To Alzheimer’S Disease, Mark Wadsworth, John S. K. Kauwe Feb 2016

Ab Blood Type And Its Genetic Relationship To Alzheimer’S Disease, Mark Wadsworth, John S. K. Kauwe

Journal of Undergraduate Research

Alzheimer’s Disease (AD) is a debilitating disease that has increased the hardship of many lives. Many people above the age of 65 have been diagnosed with this genetically complex disease, which financially and emotionally burdens those diagnosed and their families. Earlier this year a study was released that found, using a dataset of individuals that have had strokes, that individuals with AB blood type are more at risk of developing cognitive impairment[1]. This study however was not looking at the genetics of AD. My objective in performing this study was to see if there is a genetic association between Alzheimer’s …


Phylogenetic Relationships In The Neo-Tropical Lizard Family Corytophanidae, Greg Taylor, Jack Sites Feb 2016

Phylogenetic Relationships In The Neo-Tropical Lizard Family Corytophanidae, Greg Taylor, Jack Sites

Journal of Undergraduate Research

The focus of this project was 1) to determine sexual dimorphism in head and body structures in the lizard family Corytophanidae 2) analyze phylogenetic relationships between the species within the family, and 3) analyze the relationship with other lizard clades.


Association Of Tm2d3 Gene With Lateonset Of Alzheimer’S Disease In Cache County, Eleni Tukuafu, Dr. John S. K. Kauwe Feb 2016

Association Of Tm2d3 Gene With Lateonset Of Alzheimer’S Disease In Cache County, Eleni Tukuafu, Dr. John S. K. Kauwe

Journal of Undergraduate Research

It is estimated that 5.2 million Americans have Alzheimer’s disease. It is currently the 6th leading cause of death in America, killing around 500,000 seniors every year. A 68% increase of death from Alzheimer’s disease was observed from the year 2000 to 2010. These numbers are expected to continue climbing.


Anatomical Variation Of The Ulnar Collateral Ligament And Implications For Joing Stability And Surgical Rehabilitation, Jakob Gamboa, Dr. Jonathan Wisco Feb 2016

Anatomical Variation Of The Ulnar Collateral Ligament And Implications For Joing Stability And Surgical Rehabilitation, Jakob Gamboa, Dr. Jonathan Wisco

Journal of Undergraduate Research

In 1974, the first ulnar collateral ligament reconstructive surgery was performed on Los Angeles Dodgers’ pitcher, Tommy John. The damaged ligament of the medial elbow was repaired with tendons from the pitcher’s body. Since then, the surgery has been colloquially termed “Tommy John’s Surgery”, and the alarming increase of the rates of the procedure has now become a concern, being recently called an “epidemic” by the American Sports Medicine Institute1. The procedure possesses risk of complications, and can lead to shortened careers, decreased performance over time2, and can carry a heavy financial toll on individuals and …


Testing The Effect Of Antioxidants On The Pathogenesis Of Alzheimer’S Disease Through The Rage/Nf-Kb Inflammatory Pathway, Harrison Snyder, Jonathan Wisco Feb 2016

Testing The Effect Of Antioxidants On The Pathogenesis Of Alzheimer’S Disease Through The Rage/Nf-Kb Inflammatory Pathway, Harrison Snyder, Jonathan Wisco

Journal of Undergraduate Research

The Receptor for Advanced Glycation Endproducts (RAGE) is known to have a role in inflammatory processes. When produced in excess it induces oxidative stress by activating a number of ligand enzymes, resulting in the generation of excessive cytosolic reactive oxidant species. This oxidative stress then stimulates Nuclear Factor Kappa-B (NF-kB), which regulates immune response and inflammation. When RAGE is incorrectly regulated, inflammation occurs in otherwise healthy tissue, a process implicated in neurodegenerative disorders like Alzheimer’s disease. RAGE is found throughout the body and is seen in greater concentration in inflamed tissues; it has also been found in the brain tissue …


Alzheimer’S Disease And The P.V236e Variant In The Apoe Gene, Alton Chad Sorensen, John Kauwe Feb 2016

Alzheimer’S Disease And The P.V236e Variant In The Apoe Gene, Alton Chad Sorensen, John Kauwe

Journal of Undergraduate Research

I was interested in trying to validate the findings of the publication by Medway et al. concerning the SNP rs199768005 using data from the Cache Country data set. Unfortunately, of the 4703 people from our data set, only 10 were carriers. Using R statistical analysis, I found that the p-value for this SNP with an association to protect for Alzheimer’s Disease (AD) was not significant. It was similarly not significant in its association with Any AD. I also ran other models to include for factors such as education or age in conjunction with this SNP and its association with AD …


Ligament Microstructure Analysis, Michael Gillespie, Jonathan Wisco Feb 2016

Ligament Microstructure Analysis, Michael Gillespie, Jonathan Wisco

Journal of Undergraduate Research

Due to the relatively poor fiber contrast of tendons in comparison with muscles, the anatomical, and therefore, functional relationship of muscle attachments to bones via tendons has not been well mapped. We were interested in mapping the 3D gross anatomical structure of tendons using a MicroScribe 3D digitizer (GoMeasure3D, Amherst, VA), with the goal to compare fibrous architecture between tendons of various types of muscles and muscle classes. We developed a stain made of blue dye and powdered sugar to increase fiber visibility, thus allowing for 3D digitization. This technique was applied to human cadaveric calcaneal tendon and quadriceps tendon.


Analyzing Structural Differences In Quadriceps Femoris Tendon Fibers Using Microscribe Technology, Nathaniel Hainsworth, Jon Wisco Feb 2016

Analyzing Structural Differences In Quadriceps Femoris Tendon Fibers Using Microscribe Technology, Nathaniel Hainsworth, Jon Wisco

Journal of Undergraduate Research

Not all tendons and ligaments are created equally. Many have different structural characteristics based on functionality or need for stability. This turns out to be true even between different portions of the same tendon. This project’s purpose was to analyze and compare structural differences between tendon fibers of the patellar portion and quadriceps portion of the quadriceps femoris tendon. We hypothesized that there are significant structural differences between these two portions because they act very different biomechanically, as well as different in the amount of tension/strain put on each portion. We mapped individual tendon fibers of both portions using MicroScribe …


Assessment Of Biodiversity On Mount Timpanogos With A Focus On Flies, Diptera: Agromyzidae, Samantha Smith, Dr. Riley Nelson Feb 2016

Assessment Of Biodiversity On Mount Timpanogos With A Focus On Flies, Diptera: Agromyzidae, Samantha Smith, Dr. Riley Nelson

Journal of Undergraduate Research

Mount Timpanogos, with an elevation of 3,582 meters, is home to an amazing array of insect species. Through much previous effort, many have studied the insects found in American Fork Canyon leading up to Mount Timpanogos. They have still barely scratched the surface of the abundant biodiversity on the mountain. Varied temperature regimes can cause changes in insects’ life cycle and the length of their feeding period, making the collections at different elevations of Mount Timpanogos during different years of particularly great value (Petitt et al 1991). Thus the value of collections along Mount Timpanogos is two-fold; both to study …


Analysis Of Hmgcr As A Genetic Modifier For Alzheimer’S Disease, Brian Davis, Dr. John S. K. Kauwe Feb 2016

Analysis Of Hmgcr As A Genetic Modifier For Alzheimer’S Disease, Brian Davis, Dr. John S. K. Kauwe

Journal of Undergraduate Research

Alzheimer’s disease (AD) is a chronic neurodegenerative disorder that occurs predominantly later in life and represents the fourth most common cause of death in the developed world. Given the absence of curative treatment, discovering the factors related to the development of AD and the conversion from mild cognitive impairment (MCI) to AD is one of the most urgent medical mysteries affecting the aging population. The search for the identification of genes contributing to AD led to the identification of 695 candidate genes of which a surprising number are directly involved in lipid metabolism at the level of transport, synthesis, storage, …


Association Of Rare Genetics Variants To The Protection Of Alzheimer’S Disease In The Cache County Data Set, Josue David Gonzalez Murcia, John Kauwe Feb 2016

Association Of Rare Genetics Variants To The Protection Of Alzheimer’S Disease In The Cache County Data Set, Josue David Gonzalez Murcia, John Kauwe

Journal of Undergraduate Research

Alzheimer’s disease is one of the top 10 causes of death in the world and the 6th leading cause of death in the United States, with 5.5 million people diagnosed with the disease. Alzheimer’s cannot be cured, prevented or slowed. Most research with Alzheimer’s disease has been done on SNPs that have a relatively high frequency in the population this has helped facilitate researchers in finding a broad genetic pathway in the development of Alzheimer’s disease (Naj et al. 2011; Harold et al. 2009). Our research will focus on a very rare SNP, with a much lower frequency than previously …


Expanding The Freshwater Aquatic Invertebrate Identification Guide Cd, Sarah Brown, C. Riley Nelson Feb 2016

Expanding The Freshwater Aquatic Invertebrate Identification Guide Cd, Sarah Brown, C. Riley Nelson

Journal of Undergraduate Research

The Freshwater Aquatic invertebrate Identification Guide (FAIIG) was a computer program created by the C. Riley Nelson lab in 2006 to help students with the identification process of various aquatic invertebrates throughout Utah. It has been used in Bio 100 classes at Brigham Young University to help students successfully identify various aquatic invertebrate specimens from rivers and streams in Utah. The goal of this project was to work on expanding the FAIIG program to include aquatic invertebrates in North America west of the Mississippi River. As well as expanding the breadth of content, we also worked on improving the information …


Association Of Rs75932628 (R47h) With Vascular Dementia In The Cache County Study, Emily Sears, Dr. John Kauwe Feb 2016

Association Of Rs75932628 (R47h) With Vascular Dementia In The Cache County Study, Emily Sears, Dr. John Kauwe

Journal of Undergraduate Research

Vascular dementia (VaD) is a neurodegenerative disease caused by atherosclerosis, or inadequate blood flow to the brain as a result of the build-up of fat deposits, dead cells, or other cell debris on the inside of arteries. It shortens the lifespan of those affected, and severely impairs their quality of life. VaD is the second most common form of dementia, after Alzheimer’s disease, accounting for 20-30% of dementia cases. Thus far the risk factors that have been determined are non-specific to the brain: high blood pressure, high cholesterol, and high blood sugar (Roman et. al 2003). There has not been …


Assembling Benchmark Datasets For Machine Learning Classification, Parker Hollingsworth, Stephen Piccolo Feb 2016

Assembling Benchmark Datasets For Machine Learning Classification, Parker Hollingsworth, Stephen Piccolo

Journal of Undergraduate Research

Machine learning classification is a type of artificial intelligence that learns from data and makes predictions. There are many different algorithms that can be used to develop predictive models for machine learning. Generally the algorithm looks for patterns in the data and uses those patterns to make predictions on an additional data set. This type of artificial intelligence is being used increasingly in the biomedical community to predict disease diagnosis and prognosis. Although machine learning has shown to provide promising results, it is far from perfect. The accuracy of the predictive model often depends on arbitrary decisions made by researchers. …


Investigation Of Visual Systems In A New Species Of Firefly, Yelena Pacheco, Dr. Seth Bybee Feb 2016

Investigation Of Visual Systems In A New Species Of Firefly, Yelena Pacheco, Dr. Seth Bybee

Journal of Undergraduate Research

Fireflies are well known for their bioluminescent flashes causing them to be a particular group of interest concerning insect vision research. Their flashes are used for both sexual communication and as an aposematic warning to predators. Bioluminescent fireflies are known to use either a yellow-green flash or a yellow-orange flash to communicate between sexes in order to find a mate. There have been many studies concerning flash patterns’ role in sexual communication among fireflies; however, the understanding of firefly vision as a whole allows for many more untouched research possibilities. As a member of the Bybee lab I had the …


Presenilin E318g Variant And Alzheimer’S Disease Risk: The Cache Country Study, Ariel Hippen, John Kauwe Feb 2016

Presenilin E318g Variant And Alzheimer’S Disease Risk: The Cache Country Study, Ariel Hippen, John Kauwe

Journal of Undergraduate Research

Alzheimer’s disease is the leading cause of dementia in the elderly and the third most common cause of death in the United States. A vast number of genes regulate Alzheimer’s disease, including Presenilin 1 (PSEN1). It is possible that novel variants in the PSEN1 gene have an effect on Alzheimer’s disease status. A recent study suggested that one of these variants, PSEN1 E318G, significantly affects Alzheimer’s disease status in a large case-control dataset, particularly in connection with the APOEε4 allele [1].


Accepting Evolution And Believing In God: How Religious Persons Perceive The Theory Of Evolution, Katherine F. Manwaring Feb 2016

Accepting Evolution And Believing In God: How Religious Persons Perceive The Theory Of Evolution, Katherine F. Manwaring

Theses and Dissertations

Students frequently hold an incorrect view of evolution. There are several potential barriers that prevent students from engaging evolutionary theory including lack of knowledge, limited scientific reasoning ability, and religiosity. Our research provides tools for overcoming barriers related to religiosity and diagnoses the barriers preventing students from fully engaging in learning the theory of evolution. This was a two-part study. The first part of our study addressed two hypothesized barriers to learning evolutionary theory among members of The Church of Jesus Christ of Latter-day Saints (LDS or Mormon): (1) religious views stemming from incorrect understanding of the Church's neutral stance …


Water Use Of Four Commonly Planted Landscape Tree Species In A Semi-Arid Suburban Environment, Michael Cameron Bunnell Dec 2015

Water Use Of Four Commonly Planted Landscape Tree Species In A Semi-Arid Suburban Environment, Michael Cameron Bunnell

Theses and Dissertations

Native plant communities and agricultural land are commonly converted to urban areas as cities across the Western United States continue to grow and expand. This expansion is typically accompanied by afforestation where a common goal among communities is to maximize shade tree composition. Planted forests in these regions are commonly composed of introduced tree species native to mesic environments and their ability to persist is dependent on consistent irrigation inputs. Many potential ecosystem services may be derived from planting trees in urban and suburban areas; however, there are also costs associated with extensive afforestation, and shade tree cover may have …


Virulence Of Photorhabdus Spp.: Examining The Roles Of Environment, Evolution, And Genetics In Insect Mortality, Dana Blackburn Dec 2015

Virulence Of Photorhabdus Spp.: Examining The Roles Of Environment, Evolution, And Genetics In Insect Mortality, Dana Blackburn

Theses and Dissertations

Entomopathogenic nematodes (EPNs) (genera Heterorhabditis and Steinernema) kill their invertebrate hosts with the aid of a mutualistic bacterium. The bacteria (Xenorhabdus spp. for steinernematids and Photorhabdus spp. for heterorhabditids) are primarily responsible for killing the host and providing the nematodes with nutrition and defense against secondary invaders. Photorhabdus is a Gram-negative bacterium in the Enterobacteriaceae family with high virulence towards their insect hosts. To achieve high mortality rates Photorhabdus produces a variety of virulence factors such as toxins, lipases, proteases, secretion systems, and fimbriae. EPNs are amenable to laboratory rearing and mass production for biocontrol applications against insects …


Diversification And Speciation Across Sundaland And The Philippines: The Effects Of 30 Million Years Of Eustatic Flux, Luke J. Welton Dec 2015

Diversification And Speciation Across Sundaland And The Philippines: The Effects Of 30 Million Years Of Eustatic Flux, Luke J. Welton

Theses and Dissertations

I highlight two squamate lineages endemic to Southeast Asia, the Asian water monitors (Varanus salvator Complex) and the Angle-headed lizards (Agamidae: Gonocephalus), and elucidate their systematic affinities and historical biogeography. My results represent novel phylogenetic inferences, with biogeographic histories and diversification events corresponding to major climatic fluctuations over the past 30 million years. Additionally, I solidify the taxonomy and systematics of the Varanus salvator Complex, and enumerate more than a dozen Gonocephalus lineages as candidate species in need of taxonomic scrutiny. Lastly, I investigate contemporary and historical patterns of dispersal throughout Sundaland, and between Sundaland and the Philippines.


Differences In Patterns Of Reproductive Allocation Between The Sexes In Nicrophorus Orbicollis, Ashlee N. Smith, J. Curtis Creighton, Mark C. Belk Nov 2015

Differences In Patterns Of Reproductive Allocation Between The Sexes In Nicrophorus Orbicollis, Ashlee N. Smith, J. Curtis Creighton, Mark C. Belk

Faculty Publications

Organisms are selected to maximize lifetime reproductive success by balancing the costs of current reproduction with costs to future survival and fecundity. Males and females typically face different reproductive costs, which makes comparisons of their reproductive strategies difficult. Burying beetles provide a unique system that allows us to compare the costs of reproduction between the sexes because males and females are capable of raising offspring together or alone and carcass preparation and offspring care represent the majority of reproductive costs for both sexes. Because both sexes perform the same functions of carcass preparation and offspring care, we predict that they …


Gene-Expression Patterns In Peripheral Blood Classify Familial Breast Cancer Susceptibility, Stephen R. Piccolo, Irene L. Andrulis, Adam L. Cohen, Thomas Connor, Philip J. Moos, Avrum E. Spira, Saundra S. Buys, W. Evan Johnson, Andrea H. Bild Nov 2015

Gene-Expression Patterns In Peripheral Blood Classify Familial Breast Cancer Susceptibility, Stephen R. Piccolo, Irene L. Andrulis, Adam L. Cohen, Thomas Connor, Philip J. Moos, Avrum E. Spira, Saundra S. Buys, W. Evan Johnson, Andrea H. Bild

Faculty Publications

Background: Women with a family history of breast cancer face considerable uncertainty about whether to pursue standard screening, intensive screening, or prophylactic surgery. Accurate and individualized risk-estimation approaches may help these women make more informed decisions. Although highly penetrant genetic variants have been associated with familial breast cancer (FBC) risk, many individuals do not carry these variants, and many carriers never develop breast cancer. Common risk variants have a relatively modest effect on risk and show limited potential for predicting FBC development. As an alternative, we hypothesized that additional genomic data types, such as gene-expression levels, which can reflect …


Repeated Trait Evolution Driven By Divergent Natural Selection At Early And Late Stages Of Speciation, Spencer J. Ingley Oct 2015

Repeated Trait Evolution Driven By Divergent Natural Selection At Early And Late Stages Of Speciation, Spencer J. Ingley

Theses and Dissertations

Speciation – the process by which new species arise – is of fundamental importance in the biological sciences. The means by which new species arise, and the relationship among living species, has been a topic that has captivated both lay and scientific observers for centuries. In recent years, the study of speciation has enjoyed increased attention, resulting in significant advances in our understanding of how species form. Although our understanding of the processes that contribute to speciation has increased dramatically in recent years, our knowledge of how reproductive barriers accumulate as speciation proceeds is still limited. Thus, studies that evaluate …


Alternative Preprocessing Of Rna-Sequencing Data In The Cancer Genome Atlas Leads To Improved Analysis Results, Mumtahena Rahman, Laurie K. Jackson, W. Evan Johnson, Dean Y. Li, Andrea H. Bild, Stephen R. Piccolo Jul 2015

Alternative Preprocessing Of Rna-Sequencing Data In The Cancer Genome Atlas Leads To Improved Analysis Results, Mumtahena Rahman, Laurie K. Jackson, W. Evan Johnson, Dean Y. Li, Andrea H. Bild, Stephen R. Piccolo

Faculty Publications

Motivation: The Cancer Genome Atlas (TCGA) RNA-Sequencing data are used widely for research. TCGA provides ‘Level 3’ data, which have been processed using a pipeline specific to that resource. However, we have found using experimentally derived data that this pipeline produces gene-expression values that vary considerably across biological replicates. In addition, some RNA-Sequencing analysis tools require integer-based read counts, which are not provided with the Level 3 data. As an alternative, we have reprocessed the data for 9264 tumor and 741 normal samples across 24 cancer types using the Rsubread package. We have also collated corresponding clinical data for these …


Delimiting Species And Varieties Of Cycladenia Humilis (Apocynaceae), Holly Kathryn Brabazon Jul 2015

Delimiting Species And Varieties Of Cycladenia Humilis (Apocynaceae), Holly Kathryn Brabazon

Student Works

Taxonomic delimitation of rare species is vital for accurate assessments of diversity and for their conservation. Cycladenia humilis, the sole species of Cycladenia, is an enigmatic perennial widely dispersed across the western United States. Within this species there are three currently recognized varieties: C. humilis var. humilis in Northern California, C. humilis var. venusta in Southern California, and C. humilis var. jonesii in Utah and Northern Arizona. Some populations occur geographically in areas between the typical distribution of each variety and the presently accepted taxonomy inadequately addresses these populations. Using five nDNA regions, we seek to clarify relationships between current …