Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Biology

Brigham Young University

Systematics

Articles 1 - 6 of 6

Full-Text Articles in Life Sciences

Molecular Studies Of South American Teiid Lizards (Teiidae: Squamata) From Deep Time To Shallow Divergences, Derek B. Tucker Jun 2016

Molecular Studies Of South American Teiid Lizards (Teiidae: Squamata) From Deep Time To Shallow Divergences, Derek B. Tucker

Theses and Dissertations

I focus on phylogenetic relationships of teiid lizards beginning with generic and species relationship within the family, followed by a detailed biogeographical examination of the Caribbean genus Pholidoscelis, and end by studying species boundaries and phylogeographic patterns of the widespread Giant Ameiva Ameiva ameiva. Genomic data (488,656 bp of aligned nuclear DNA) recovered a well-supported phylogeny for Teiidae, showing monophyly for 18 genera including those recently described using morphology and smaller molecular datasets. All three methods of phylogenetic estimation (two species tree, one concatenation) recovered identical topologies except for some relationships within the subfamily Tupinambinae (i.e. position of …


Testing Crayfish Evolutionary Hypotheses With Phylogenetic Methods, Jesse W. Breinholt May 2012

Testing Crayfish Evolutionary Hypotheses With Phylogenetic Methods, Jesse W. Breinholt

Theses and Dissertations

This dissertation focuses on increasing the understanding of the evolution processes that have contributed to the diversification of freshwater crayfish. Chapter one estimates the divergence time of the three crayfish families and tests the hypothesis that diversification is tied to the break-up of Pangaea, Gondwanna, and Laurasia. I find that the families of crayfish diverged prior to or in association with the break-up of the three super continents. Chapter two addresses the evolutionary history of the genus Cambarus, using molecular data to test hypotheses of relationships based on chela and carapace morphology. The results provide evidence that the morphology used …


The Origins, Evolution, And Phylogeny Of The Praying Mantises (Dictyoptera: Mantodea), Gavin John Svenson Jul 2007

The Origins, Evolution, And Phylogeny Of The Praying Mantises (Dictyoptera: Mantodea), Gavin John Svenson

Theses and Dissertations

The relatively small insect order Mantodea (praying mantises) is comprised of approximately 2,366 described species distributed in 436 genera. Members of the group occupy diverse habitats and are distributed across the globe, though their greatest numbers and diversity are concentrated primarily in the tropics. Though continental endemism is common, many groups have a broad global distribution. An immense diversity of morphology is exhibited across the order with adult mantises ranging in size from 2cm to ~25cm, and appearing like a dead leaf, a piece of quartz rock, or a blade of grass. The diversification and specialization of mantises in ecologically …


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 …


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 …


Evolution And Phylogeny Of Basal Winged Insects With Emphasis On Mayflies (Ephemeroptera), Thomas H. Ogden Nov 2004

Evolution And Phylogeny Of Basal Winged Insects With Emphasis On Mayflies (Ephemeroptera), Thomas H. Ogden

Theses and Dissertations

Ephemeroptera (mayflies) is a monophyletic group of semi-aquatic pterygote insects, comprising 3083 species, 376 genera, and 37 described families and are present on all continents, excluding Antarctica, being associated with freshwater and brackish water habitats. The order is unique among pterygote insects in possessing functional wings at the penultimate molt (subimago stage), prior to the full development of genitalia; in all other insects the presence of functional wings occurs only after the final molt. The purpose of this dissertation is to use molecular and morphological data, in order to investigate the position of the order Ephemeroptera among other insect orders, …