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A Setback To The Dialogue: Response To Huston Smith, Ursula Goodenough Jun 2001

A Setback To The Dialogue: Response To Huston Smith, Ursula Goodenough

Biology Faculty Research

Huston Smith's book, Why Religion Matters, offers an eloquent evocation of mystical sensibility. Unfortunately, along the way, he offers a strongly negative and often inaccurate account of the scientific worldview, the claim being that the science is laying siege to the spiritual.


Comparative Phylogeography Of Mesoamerican Highland Rodents: Concerted Versus Independent Response To Past Climatic Fluctuations, Duke S. Rogers, Jack Sullivan, Elizabeth Arellano Jun 2001

Comparative Phylogeography Of Mesoamerican Highland Rodents: Concerted Versus Independent Response To Past Climatic Fluctuations, Duke S. Rogers, Jack Sullivan, Elizabeth Arellano

Faculty Publications

The phylogeography of Sumichrast's harvest mouse (Reithrodontomys sumichrasti) was examined through maximumlikelihood and parsimony analyses of 1,130 bp of mitochondrial Cytochrome b sequence data from 43 individuals. The phylogeography of this Middle American highland forest-dwelling species was compared to that previously published for the codistributed Aztec deer mouse complex (Peromyscus aztecus/Peromyscus hylocetes complex) in order to test competing hypotheses of concerted versus independent responses of codistributed forms to past climatic fluctuations. Qualitatively, there were strong similarities in the phylogeographic patterns of the two groups, yet there were also areas of incongruence. Likelihood-ratio tests (Kishino-Hasegawa-Templeton and parametric bootstrap tests) indicated that …


Restoration Of Fish Habitat In The Provo River: A Multispecies Approach, Mark C. Belk Jun 2001

Restoration Of Fish Habitat In The Provo River: A Multispecies Approach, Mark C. Belk

Faculty Publications

Historically, the Provo river, located in Utah and Wasatch Cos., Utah, was a clear-flowing stream with headwaters in the western edge of the Uinta mountains that emptied into Utah Lake near Provo, Utah. The river had a wide flood plain and a braided channel, especially in the Heber valley and Utah valley areas. Diversion of water and construction of water storage facilities began in the late 1800's and intensified in the 1900's. Deer Creek reservoir was built in the 1950's and diking and channelization continued until the construction of Jordanelle reservoir in the late 1980's. The Provo River Restoration Project, …


Functional Properties Of Slow And Fast Gastrocnemius Muscle Fibers After A 17-Day Spaceflight, Jeffrey J. Widrick, Janell Romatowski, Kris M. Norenberg, Shannon T. Knuth, James L. W. Bain, Danny A. Riley, S. W. Trappe, Todd A. Trappe, David Costill, Robert H. Fitts Jun 2001

Functional Properties Of Slow And Fast Gastrocnemius Muscle Fibers After A 17-Day Spaceflight, Jeffrey J. Widrick, Janell Romatowski, Kris M. Norenberg, Shannon T. Knuth, James L. W. Bain, Danny A. Riley, S. W. Trappe, Todd A. Trappe, David Costill, Robert H. Fitts

Biological Sciences Faculty Research and Publications

The purpose of this investigation was to study the effects of a 17-day spaceflight on the contractile properties of individual fast- and slowtwitch fibers isolated from biopsies of the fast-twitch gastrocnemius muscle of four male astronauts. Single chemically skinned fibers were studied during maximal Ca2+-activated contractions with fiber myosin heavy chain (MHC) isoform expression subsequently determined by SDS gel electrophoresis. Spaceflight had no significant effect on the mean diameter or specific force of single fibers expressing type I, IIa, or IIa/IIx MHC, although a small reduction in average absolute force (Po) was observed for the type …


The Wings Of Bombyx Mori Develop From Larval Discs Exhibiting An Early Differentiated State: A Preliminary Report, Madhuri Kango-Singh, Amit Singh, K. P. Gopinathan Jun 2001

The Wings Of Bombyx Mori Develop From Larval Discs Exhibiting An Early Differentiated State: A Preliminary Report, Madhuri Kango-Singh, Amit Singh, K. P. Gopinathan

Biology Faculty Publications

Lepidopteran insects present a complex organization of appendages which develop by various mechanisms. In the mulberry silkworm, Bombyx mori, a pair of meso- and meta-thoracic discs located on either side in the larvae gives rise to the corresponding fore- and hind-wings of the adult. These discs do not experience massive cell rearrangements during metamorphosis and display the adult wing vein pattern. We have analysed wing development in B. mori by two approaches, viz., expression of patterning genes in larval wing discs, and regulatory capacities of larval discs following explantation or perturbation. Expression of Nubbin is seen all over the presumptive …


Comparison Of The Quantification Of Caffeine In Human Plasma By Gas Chromatography And Elisa, A. B. Carregaro, W. E. Woods, Thomas Tobin, A. Queiroz-Neto Jun 2001

Comparison Of The Quantification Of Caffeine In Human Plasma By Gas Chromatography And Elisa, A. B. Carregaro, W. E. Woods, Thomas Tobin, A. Queiroz-Neto

Veterinary Science Faculty Publications

In the present study we evaluated the precision of the ELISA method to quantify caffeine in human plasma and compared the results with those obtained by gas chromatography. A total of 58 samples were analyzed by gas chromatography using a nitrogen-phosphorus detector and routine techniques. For the ELISA test, the samples were diluted to obtain a concentration corresponding to 50% of the absorbance of the standard curve. To determine whether the proximity between the I50 of the standard curve and that of the sample would bring about a more precise result, the samples were divided into three blocks according …


Salivary Acinar Cells From Aquaporin 5-Deficient Mice Have Decreased Membrane Water Permeability And Altered Cell Volume Regulation, Carissa M. Krane, James E. Melvin, Ha-Van Nguyen, Linda Richardson, Jennifer E. Towne, Thomas Doetschman, Anil G. Menon Jun 2001

Salivary Acinar Cells From Aquaporin 5-Deficient Mice Have Decreased Membrane Water Permeability And Altered Cell Volume Regulation, Carissa M. Krane, James E. Melvin, Ha-Van Nguyen, Linda Richardson, Jennifer E. Towne, Thomas Doetschman, Anil G. Menon

Biology Faculty Publications

Aquaporins (AQPs) are channel proteins that regulate the movement of water through the plasma membrane of secretory and absorptive cells in response to osmotic gradients. In the salivary gland, AQP5 is the major aquaporin expressed on the apical membrane of acinar cells. Previous studies have shown that the volume of saliva secreted by AQP5-deficient mice is decreased, indicating a role for AQP5 in saliva secretion; however, the mechanism by which AQP5 regulates water transport in salivary acinar cells remains to be determined. Here we show that the decreased salivary flow rate and increased tonicity of the saliva secreted byAqp5 …


Ecology Of Audubon's Shearwaters (Puffinus Lherminieri) At San Salvador, Bahamas, Neville Anthony Trimm Jr. Jun 2001

Ecology Of Audubon's Shearwaters (Puffinus Lherminieri) At San Salvador, Bahamas, Neville Anthony Trimm Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

The Audubon's Shearwater (Pqffinus lherminieri), nearly pantropical in distribution, remains a poorly studied species. The subspecies P. l. lherminieri is endemic to the West Indies region. An estimated 5,000 pairs inhabit the Caribbean, but there has been a substantial decline with many colonies becoming extirpated. It is thought that as many as 3,000 pairs (60% of the West Indian population) nest in the Bahamas. In May and June of 2000, I collected data on shearwater demographics, colony site selection, burrow microhabitat, chick behavior and the effect of moonlight on the onset of calling of the Audubon's Shearwaters nesting on …


Ecology Of The Endangered Sandy Cay Rock Iguana, Cyclura Rileyi Cristata, In The Bahamas, Shawn Kendall Fry Jun 2001

Ecology Of The Endangered Sandy Cay Rock Iguana, Cyclura Rileyi Cristata, In The Bahamas, Shawn Kendall Fry

Loma Linda University Electronic Theses, Dissertations & Projects

In this thesis I present the results of a study on the population demographics and home range size of Cyclura rileyi cristata. There are eight species of West Indian rock iguanas, genus Cyclura. All are endangered, including C. rileyiwhich is endemic to the Bahamas. One of three recognized subspecies, C. r. cristatalives on a single cay in the Exumas chain and is among the most endangered lizards in the world. Various size measurements indicate that this taxon is among the smallest within the genus. Distance surveys and a Lincoln-Petersen estimate based on resightings of marked iguanas …


First Nesting Records Of The Black Phoebe (Sayornis Nigricans) In Southernmost Texas, Timothy Brush Jun 2001

First Nesting Records Of The Black Phoebe (Sayornis Nigricans) In Southernmost Texas, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

No abstract provided.


Analysis And New Records Of Billfish (Teleostei: Perciformers: Istiophoridae) From The Yorktown Formation, Early Pliocene Of Eastern North Carolina At Lee Creek Mine, Harry L. Fierstine May 2001

Analysis And New Records Of Billfish (Teleostei: Perciformers: Istiophoridae) From The Yorktown Formation, Early Pliocene Of Eastern North Carolina At Lee Creek Mine, Harry L. Fierstine

Biological Sciences

Five species of the billfish family Istiophoridae (Istiophorus platypterus (Shaw and Nodder), Makaira indica (Cuvier), M. nigricans Lacépède, M. purdyi Fierstine, Tetrapturus albidus Poey) were identified from approximately 500 separate bones collected in the Yorktown Formation (early Pliocene) at Lee Creek Mine, North Carolina. This is the only record of M. purdyi, the first fossil record of the genus Tetrapturus (specifically T. albidus), the second fossil record of I. platypterus and M. indica, and the first record of I. platypterus, M. indica, M. nigricans, and T. albidus from fossil deposits bordering the Atlantic Ocean.

Identification was …


Neuromotor And Cognitive Development In Children With Cerebral Palsy In Relation To Neural Plasticity, Vaniecea Pollard May 2001

Neuromotor And Cognitive Development In Children With Cerebral Palsy In Relation To Neural Plasticity, Vaniecea Pollard

McCabe Thesis Collection

Infants with neurological disabilities, such as cerebral palsy (CP) and Down syndrome (DS), show severe delays in motor and cognitive development relative to chronological age. Involvement of neural plasticity as a treatment of such neurological disorders is increasingly being seen. Previous studies have found that interventions involving sensory linked motor performance have been critical in facilitating motor improvement. The purpose of this study was to compare self-initiated mobility in children with CP and DS. Three infants, ages 8, 9, and 22 months, with diagnoses of no CP, DS, and CP respectively, participated in the study. The infants were videotaped in …


16s Ribosomal Dna Terminal Restriction Fragment Pattern Analysis Of Bacterial Communities In Feces Of Rats Fed Lactobacillus Acidophilus Ncfm, Christopher W. Kaplan, Johanna C. Astaire, M. E. Sanders, Bandaru S. Reddy, Christopher L. Kitts May 2001

16s Ribosomal Dna Terminal Restriction Fragment Pattern Analysis Of Bacterial Communities In Feces Of Rats Fed Lactobacillus Acidophilus Ncfm, Christopher W. Kaplan, Johanna C. Astaire, M. E. Sanders, Bandaru S. Reddy, Christopher L. Kitts

Biological Sciences

16S ribosomal DNA terminal restriction fragment patterns from rat fecal samples were analyzed to track the dynamics of Lactobacillus acidophilus NCFM and discern bacterial populations that changed during feeding with NCFM. Lactobacillus johnsonii and Ruminococcus flavefaciens were tentatively identified as such bacterial populations. The presence of L. johnsonii was confirmed by isolation from feces.


Effect Of Forest Age On Density Of Stream-Breeding Amphibians In Skamania County, Washington, Craig A. Steele May 2001

Effect Of Forest Age On Density Of Stream-Breeding Amphibians In Skamania County, Washington, Craig A. Steele

Biology

Because the ranges of stream-breeding amphibians in the Pacific Northwest occur partly on industrial timberlands, it is valuable to study population distributions of these animals in forest environments that rarely reach old growth status and are subject to timber harvest on a regular basis. To determine how short-term changes in forest age affect the density of stream-breeding amphibians, first-order streams located on private industrial timberlands in Skamania County, Washington, were sampled during the summers of 1998 and 1999. Species captured included Dicamptodon tenebrosus, Dicamptodon copei, Rhyacotriton cascadae, and Ascaphus truei. Regression tree analysis showed that relative …


Switching Between Intensive And Extensive Searching In Predators Of Heterogeneously Distributed Prey, Zy Biesinger May 2001

Switching Between Intensive And Extensive Searching In Predators Of Heterogeneously Distributed Prey, Zy Biesinger

Biology

Many predators of patchily distributed prey are thought to increase their searching efficiency by alternating between extensive and intensive searching behavior. To test the effects of predator satiation and prey density on a ladybird's choice of searching mode, I performed experiments in which larvae of different hunger levels experienced different prey encounter rates. Using traditional measures, I found a beetle's satiation level to have no effect. The prey encounter rate had an effect on two of three traditional measures. Less traditional methods, fractal dimension analysis and Fourier slope analysis, supported the conclusions obtained using traditional measures. Analysis of movement patterns …


Assemblages Of Spiders On Shrubs In Semiarid Environments: Experimental Models Of Shrub Architecture, Michael W. Heikkinen May 2001

Assemblages Of Spiders On Shrubs In Semiarid Environments: Experimental Models Of Shrub Architecture, Michael W. Heikkinen

Biology

Assemblages of spiders on big sagebrush are dominated by salticids. The pattern could result from many salticids in the colonist pool and random distribution as spiders disperse or a selection process by which spiders are choosing to remain on big sagebrush after initial colonization. Choices may be based on insect prey on the shrubs or related to the plant's physical attributes. Habitat structure has been associated with the distribution of many animals, and plant architecture influences the distribution of spiders. Models of big sagebrush were constructed to test plant architecture variables that spiders may use as cues in deciding to …


Phylogenetic Relationships, Taxonomy, And Evolution Of Host Choice In Diadasia (Hymenoptera: Apoidea), Sedonia D. Sipes May 2001

Phylogenetic Relationships, Taxonomy, And Evolution Of Host Choice In Diadasia (Hymenoptera: Apoidea), Sedonia D. Sipes

Biology

I examined the phylogenetic relationships, taxonomy, and evolution of host choice in Diadasia, a genus of New World bees. Diadasia species are particularly interesting because they are considered pollen specialists. Females of each species are believed to provision their nests with pollen from only a few closely related plant taxa. At the same time, the choice of floral hosts within the genus is diverse, and includes five distantly related plant families: Malvaceae, Onagraceae, Convolvulaceae, Asteraceae, and Cactaceae. To estimate phylogenetic relationships within this group, I sequenced ~ 2 kb of the mitochondrial genes CO I and II and tRNA …


Diversity, Distribution, And Abundance Of Flower-Visiting Apoidea (Hymenoptera) On Sand Dunes Of The West Desert Of Utah, Trent R. Toler May 2001

Diversity, Distribution, And Abundance Of Flower-Visiting Apoidea (Hymenoptera) On Sand Dunes Of The West Desert Of Utah, Trent R. Toler

Biology

Three habitats (dunes, mountain slopes, and mud flats) were surveyed for bees (Hymenoptera: Apoidea) in the Bonneville Basin in Utah on lands owned by the U.S. military, the Dugway Proving Grounds and the southern section of the Utah Testing and Training Range, in the summers of 1997 and 1998. Study of dune habitat was emphasized, as it is thought to be important for bees in arid climates, particularly in providing nesting substrate and sources of plant pollen and nectar. Species compositions of bees were determined using pan traps at 16 sites (in three habitats) in 1997, and at 5 dune …


Avian Food Selection With Application To Pesticide Risk Assessment: Are Dead And Dessicated Insects A Desirable Food Source?, Jennifer M. Stafford May 2001

Avian Food Selection With Application To Pesticide Risk Assessment: Are Dead And Dessicated Insects A Desirable Food Source?, Jennifer M. Stafford

Biology

When evaluating avian pesticide exposure, a number of factors must be considered to form an accurate risk assessment. In the past, such assessments have been conducted with substantial uncertainty about avian consumption of exposed food items. One such uncertain factor is whether or not the avian species would consume contaminated invertebrates that were killed by a chemical application, and which may present an increasing concentration of the chemical as they desiccate over time. Therefore I asked the question: do birds select dead and desiccated insects as food items? I addressed the research question in two steps. First, a laboratory study …


Variations In The Histamine Content Of Mink Testes Due To Injections Of Gonadotrophic Hormones And Application Of Free Radicals In Vitro, Grant I. Wilson May 2001

Variations In The Histamine Content Of Mink Testes Due To Injections Of Gonadotrophic Hormones And Application Of Free Radicals In Vitro, Grant I. Wilson

Biology

It was hypothesized that gonadotropic hormones and oxygen-derived free radicals affect histamine production in the testes. Luteinizing hormone, follicle stimulating hormone, prolactin, a combination of these three hormones, or saline (controls) were injected for either 4 or 7 days into seven wild-type (demi) and seven dark male mink per group. All mink were euthanized with carbon monoxide. Their testes were removed and frozen on dry ice. The histamine content was analyzed using radioimmunoassay. The control wild-type mink injected for either 4 or 7 days had histamine values of 8.15 μg/g and 7.56 μg/g, respectively. In wild-type mink, there was no …


Storm-Related Suspended Particulate Matter In Little Westham Creek, John R. Jordan May 2001

Storm-Related Suspended Particulate Matter In Little Westham Creek, John R. Jordan

Master's Theses

Properties of a watershed regulate the amount of suspended particulate matter (SPM) in a stream. The present study examined relationships between storm-related SPM and impervious area and tree cover in the suburban watershed of Little Westham Creek, Richmond, Virginia during Summer and early Fall, 1999. SPM concentration, SPM discharge, and turbidity due to clay, silt and sand, and the areas of impervious surface and tree stand cover in the watershed were measured at three sites. SPM concentration, SPM discharge, and turbidity due to clay were greater upstream than downstream. The percentages of watershed area covered by impervious surfaces and tree …


A Quantitative Histological Evaluation Of Articular Cartilage And Regenerated Tissue From A Stress-Shielded In Vivo Model, Jeremy Matthew Kupsco May 2001

A Quantitative Histological Evaluation Of Articular Cartilage And Regenerated Tissue From A Stress-Shielded In Vivo Model, Jeremy Matthew Kupsco

Master's Theses

Cartilage does not normally repair lesions. Cartilage induced to regenerate experimentally degenerates quickly, perhaps because stresses of articulation do not allow normal extracellular matrix to develop. I examined normal cartilage from dogs, pigs, rabbits, and humans, and canine patellar tissue regenerated in a stress-shielded environment. SEM of canine cartilage after trypsin digestion revealed meshworks of fibrils oriented with a bias normal to the surface in the deep zone, random in the middle zone, and parallel to the surface in the superficial zone. SEM after freeze-fracture revealed tubules of fibrils within the deep zone. I found no evidence of collagen arcades. …


Natural History And Roosting Ecology Of The Eastern Pipistrelle, Pipistrellus Subflavus, Jacques Pierre Veilleux May 2001

Natural History And Roosting Ecology Of The Eastern Pipistrelle, Pipistrellus Subflavus, Jacques Pierre Veilleux

All-Inclusive List of Electronic Theses and Dissertations

A study concerning the natural history and roosting ecology of the eastern pipistrelle, Pipistrellus subtlavus, was conducted from 1997 to 2000, in southern Vigo County, Indiana. 111 Females began forming pre-maternity colonies during early May, and parturition began during late June. Pre-maternity colonies averaged 3.7 ± 1.9 individuals, and maternity colonies averaged 4.4 ± 2.4 individuals. Young pipistrelles first became volant during the third and fourth weeks of July. Pipistrelles were located in 59 roost trees. All roosts were located in foliage, either in clusters of dead leaves (n = 40) or in live foliage (n = 19). Oaks (Ouercus …


Rna Levels And Activity Of Flowering Locus C Are Modified In Mixed Genetic Backgrounds Of Arabidopsis Thaliana, Michael Schläppi May 2001

Rna Levels And Activity Of Flowering Locus C Are Modified In Mixed Genetic Backgrounds Of Arabidopsis Thaliana, Michael Schläppi

Biological Sciences Faculty Research and Publications

Flowering time and FLOWERING LOCUS C (FLC) RNA levels were analyzed in different accessions of Arabidopsis thaliana and in mixed genetic backgrounds resulting from crosses between accessions. Dominant alleles of FRIGIDA (FRI) promote accumulation of FLC RNA, which in turn promotes late flowering. Although the coding regions of sequenced FLC alleles are identical, some accessions have genetically weak alleles that do not promote late flowering in the presence of FRI. In this study, a new weak allele of FLC with open reading frame identity to previously sequenced alleles was isolated from a Niederzenz (Nd) accession. …


Characterization Of A Non-Ribosomal Peptide From Agrobacterium Tumefaciens, Graham Strub May 2001

Characterization Of A Non-Ribosomal Peptide From Agrobacterium Tumefaciens, Graham Strub

Honors Theses

The current efforts underway to sequence the genome of Agrobacterium tumefaciens have led to the discovery of a large region of DNA (52kb) with a strong homology to several polyketide synthetase genes. This was a matter of great interest to the Agrobacterium project; no current literature documents the production of a polyketide or non:iibosomal peptide from Agrobacterium. Furthermore, the multi-domain enzymes coded by these polyketide synthetase genes in other bacterial species are responsible for synthesizing several toxins, many which act as antibiotic agents {8, 9, 12, 16). This was also of great interest, since Agrobacterium is not known to produce …


The Effects Of Parental Age And Housing Type On The Reproductive Success Of The Purple Martin (Progne Subis Subis), Jessica A. Eads May 2001

The Effects Of Parental Age And Housing Type On The Reproductive Success Of The Purple Martin (Progne Subis Subis), Jessica A. Eads

Electronic Theses and Dissertations

The reproductive success of the Purple Martin is dependent upon many factors. This study measured reproductive success of the Purple Martin (Progne subis subis) based on parental age and type of housing used. Reproductive parental ages consist of adults (experienced breeders) and subadults (first time breeders). Housing types included in this study were aluminum housing, wooden housing, plastic gourds, natural gourds, SuperGourds, and mailbox housing. The reproductive success was defined as the percentage of the original clutch that fledged. Study sites were located in Alabama, Indiana, North Carolina, Oklahoma, Tennessee, and Virginia. Pairs mating nonassortatively by age group …


Trophic Cascades, Nutrients, And Lake Productivity: Whole-Lake Experiments, Stephen R. Carpenter, Jonathan J. Cole, James R. Hodgson, James F. Kitchell, Michael L. Pace, Darren Bade, Kathryn L. Cottingham May 2001

Trophic Cascades, Nutrients, And Lake Productivity: Whole-Lake Experiments, Stephen R. Carpenter, Jonathan J. Cole, James R. Hodgson, James F. Kitchell, Michael L. Pace, Darren Bade, Kathryn L. Cottingham

Dartmouth Scholarship

Responses of zooplankton, pelagic primary producers, planktonic bacteria, and CO2 exchange with the atmosphere were measured in four lakes with contrasting food webs under a range of nutrient enrichments during a seven-year period. Prior to enrichment, food webs were manipulated to create contrasts between piscivore dominance and planktivore dominance. Nutrient enrichments of inorganic nitrogen and phosphorus exhibited ratios of N:P > 17:1, by atoms, to maintain P limitation. An unmanipulated reference lake, Paul Lake, revealed baseline variability but showed no trends that could confound the interpretation of changes in the nearby manipulated lakes. Herbivorous zooplankton of West Long Lake (piscivorous fishes) …


Hydrodynamic Properties Of Dna Polymerases, Angela Sherell Byrd May 2001

Hydrodynamic Properties Of Dna Polymerases, Angela Sherell Byrd

Honors Capstones

No abstract provided.


Range Extensions Of The Seaweeds Codium Taylorii And Caulerpa Prolifera Into The Lower Laguna Madre, Texas, Hudson R. Deyoe, Donald L. Hockaday May 2001

Range Extensions Of The Seaweeds Codium Taylorii And Caulerpa Prolifera Into The Lower Laguna Madre, Texas, Hudson R. Deyoe, Donald L. Hockaday

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Between January 1999 and April 2000 two chlorophyte algae, Codium taylorii Silva and Caulerpa prolifera F. obovata (Forsskal) Lamouroux were found in the lower Laguna Madre (LLM). Both are coenocytic algae and are members of the chlorophyte class Bryopsidophyceae ( van den Hoek et al. 1995). The species descriptions in Taylor (1960) were used in the identification of the specimens. Her barium specimens have been deposited at the University of Texas- Pan American Coastal Studies Laboratory (accession numbers COlO - C. prolifera, COl 1 - C. taylorii) , University of California at Berkeley (UC 1753606 - C. taylorii) , University …


Genetic Relationships Between Two Rare Plant Species, Aliciella Caespitosa And A. Tenuis, And Their Putative Progenitor, A. Subnuda, Carrie L. Mccracken May 2001

Genetic Relationships Between Two Rare Plant Species, Aliciella Caespitosa And A. Tenuis, And Their Putative Progenitor, A. Subnuda, Carrie L. Mccracken

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Isolated populations have potential to become new species that should have less genetic variation than their ancestors. Small populations are more likely to lose genetic variation, which is, thus, expected to be greater in ancestors. Aliciella caespitosa and A. tenuis, two endemic species, may be derived from small populations of A. subnuda, a widespread species. Chloroplast DNA sequences were used to test this hypothesis. Allozyme data were used to compare genetic variation and numbers of alleles. Chloroplast data do not support the proposed relationships between A. subnuda and the other two species. Allozyme data were not more variable …