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Biology

Brigham Young University

2005

Articles 1 - 7 of 7

Full-Text Articles in Life Sciences

Applications Of Phylogenetics To Issues In Freshwater Crayfish Biology, Keith A. Crandall Nov 2005

Applications Of Phylogenetics To Issues In Freshwater Crayfish Biology, Keith A. Crandall

Faculty Publications

Freshwater crayfish have served as model organisms for over 125 years in scientific research, from areas such as neurobiology and vision research to conservation biology and evolution. Recently, evolutionary histories in the form of phylogenies have served as a critical foundation for testing hypotheses in such diverse research areas as well. In this article, I review the amazing diversity of freshwater crayfish, especially in a phylogenetic context and explore how these evolutionary histories have informed crayfish biology and can be used powerfully in the future to guide research in a diversity of areas. Throughout the article, I draw on examples …

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Phylogeny And Biogeography Of Ice Crawlers (Insecta: Grylloblattodea): Evidence From Six Molecular Loci, Karl J. Jarvis Jun 2005

Phylogeny And Biogeography Of Ice Crawlers (Insecta: Grylloblattodea): Evidence From Six Molecular Loci, Karl J. Jarvis

Theses and Dissertations

Ice crawlers (Insecta: Grylloblattodea) are rarely encountered insects that consist of five genera representing 26 species from North America and Asia. Asian grylloblattids are the most diverse, but North American ice crawlers (genus Grylloblatta) are known for their adaptation to cold conditions. Phylogenetic relationships among grylloblattid species and genera are not known. Late Pleistocene glaciations had a major effect on the current Grylloblatta distribution, because their specific habitat requirements restrict them to small geographical areas. Six genes were sampled in 37 individuals for 18S rRNA, 28S rRNA, histone 3, 12S rRNA, 16S rRNA, and cytochrome oxidase II (COII) from 27 …

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Digestibility, Nitrogen Balance, And Blood Metabolites In Llama And Alpaca Fed Barley And Barley Alfalfa Forages., Heather Loree Davies Apr 2005

Digestibility, Nitrogen Balance, And Blood Metabolites In Llama And Alpaca Fed Barley And Barley Alfalfa Forages., Heather Loree Davies

Theses and Dissertations

These projects were conducted to determine the digestibility of forage diets with differing CP levels in llamas and alpacas. The Utah study was designed to compare llama and alpaca nutritional parameters to determine if nutritional recommendations for llamas can be directly extrapolated to alpacas. The first study evaluated the effects of forage quality on blood metabolites and nitrogen balance in mature, intact male llamas (n = 4, 36 ± 4.4 months, 87 ± 17 kg) at high altitude in Letanias, Bolivia (4,267 m = aprox.14,000 ft above sea level). A second experiment was conducted with eight adult gelded camelids (n …

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Phylogenetic Relationship Of Forest Spiny Pocket Mice (Genus Heteromys) Inferred From Mitochondrial And Nuclear Markers With Implications For Species Boundaries, Malinda Wallentine Gonzalez Mar 2005

Phylogenetic Relationship Of Forest Spiny Pocket Mice (Genus Heteromys) Inferred From Mitochondrial And Nuclear Markers With Implications For Species Boundaries, Malinda Wallentine Gonzalez

Theses and Dissertations

I constructed a best estimate phylogeny based on congruence of multiple data sources. In recent years molecular data has been used both to construct phylogenies of taxonomic groups and to aid in the delimitation of new species. I generated and analyzed sequence data for forest spiny pocket mice (Genus Heteromys) for the mitochondrial gene cyt b (1143 bp) and two nuclear gene segments MYH2 (252 bp) and EN2 (189 bp). I used maximum parsimony and Bayesian analyses to infer relationships among species and to provide a framework for using a species delimitation method to investigate the possibility of multiple …

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Vegetation Response Of A Wyoming Big Sagebrush (Artemisia Tridentata Ssp. Wyomingensis) Community To 6 Mechanical Treatments In Rich County, Utah, Daniel David Summers Mar 2005

Vegetation Response Of A Wyoming Big Sagebrush (Artemisia Tridentata Ssp. Wyomingensis) Community To 6 Mechanical Treatments In Rich County, Utah, Daniel David Summers

Theses and Dissertations

In recent years, the importance of sagebrush to shrub-steppe ecosystems and associated plant and animal species has been recognized. The historical removal of herbaceous species by excessive and uncontrolled livestock grazing on many of our sagebrush ecosystems has resulted in a stagnant state where dense, competitive stands of sagebrush prevent herbaceous species from recovering. Most early research on sagebrush control was directed toward eradication to increase herbaceous forage for livestock production, rather than sagebrush thinning to improve shrub vigor and understory production for wildlife habitat and community diversity. Mechanical treatments have the ability to retain shrub and herbaceous components, while …

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Phylogenetic History, Morphological Parallelism, And Speciation In A Complex Of Appalachian Salamanders (Genus: Desmognathus), Nathan D. Jackson Mar 2005

Phylogenetic History, Morphological Parallelism, And Speciation In A Complex Of Appalachian Salamanders (Genus: Desmognathus), Nathan D. Jackson

Theses and Dissertations

Understanding the mechanisms that generate shared morphologies across closely related taxa is important when identifying distinct evolutionary lineages using morphological characters. Desmognathus salamanders are an ideal group for testing hypotheses concerning the correlation between morphological similarity and genetic exchange within and among nominal species due to a pattern of high discordance between the two. Phylogeographic hypotheses are tested for populations of the D. quadramaculatus species complex throughout southern Appalachia by combining phylogenetic and population genetic methods with geographical information. Phylogenetic and phylogeographic inferences are then assessed in conjunction with morphological characteristics that have traditionally diagnosed taxonomic entities to understand the …

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Biochemical And Molecular Nutrition Blocks As Dietary Supplements In Llamas (Lama Glama) In The Last Third Of The Gestation Period Of The Ceac, Janette Illanes Callejas Jan 2005

Biochemical And Molecular Nutrition Blocks As Dietary Supplements In Llamas (Lama Glama) In The Last Third Of The Gestation Period Of The Ceac, Janette Illanes Callejas

Theses and Dissertations

The present work consisted in the use of biochemical and molecular nutrition blocks (BMN) in llamas during the last third of the gestation period, at the Agricultural Experiment Center of Condori (CEAC), located 49 km north of the city of Oruro, and 12 km north of the Caracollo population, in the province of Cercado. For this research work, we used 20 pregnant llamas in the last third of their gestation period, between the ages of 2 and 3 years old, 10 of which belonged to the Khara breed, and 10 to the Thampulli breed. Two corrals of 7 x 7 …

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