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Full-Text Articles in Life Sciences
Phylogenetic Relationships And Evolution Of Snakes, Alex Figueroa
Phylogenetic Relationships And Evolution Of Snakes, Alex Figueroa
University of New Orleans Theses and Dissertations
Snakes represent an impressive evolutionary radiation of over 3,500 widely-distributed species, categorized into 515 genera, encompassing a diverse range of morphologies and ecologies. This diversity is likely attributable to their distinctive morphology, which has allowed them to populate a wide range of habitat types within most major ecosystems. In my first chapter, I provide the largest-yet estimate of the snake tree of life using maximum likelihood on a supermatrix of 1745 taxa (1652 snake species + 7 outgroup taxa) and 9,523 base pairs from 10 loci (5 nuclear, 5 mitochondrial), including previously unsequenced genera (2) and species (61). I then …
The Tettigoniidae (Orthoptera: Ensifera): Phylogeny, Origins, And Leaf-Like Crypsis, Joseph D. Mugleston
The Tettigoniidae (Orthoptera: Ensifera): Phylogeny, Origins, And Leaf-Like Crypsis, Joseph D. Mugleston
Theses and Dissertations
Tettigoniidae (katydids) has more than 7200 species and is the largest family within the insect order Orthoptera. Their unique biology including leaf-like crypsis, acoustic signaling, and courtship rituals garners much of their academic attention. However, the taxonomy of katydids is chaotic and previous to these studies, little work had been done to decipher the phylogenetic relationships within this family. Without a robust phylogenetic framework, questions regarding the evolution of katydid disguises including the leaf-like crypsis cannot be addressed. This dissertation contains three chapters. Chapter 1 provides the first phylogenetic hypothesis focusing on Tettigoniidae. In this chapter we show a character …
Phylogenetic Analysis Of Human Cytomegalovirus Pus27 And Pus28: Ascertaining An Independent Or Linked Evolutionary History, Jessica A. Scarborough
Phylogenetic Analysis Of Human Cytomegalovirus Pus27 And Pus28: Ascertaining An Independent Or Linked Evolutionary History, Jessica A. Scarborough
Undergraduate Honors Theses
Human cytomegalovirus (HCMV) is a widespread pathogen that is particularly skilled at evading immune detection and defense mechanisms, largely due to extensive co-evolution with its host’s immune system. One aspect of this co-evolution involves the acquisition of four virally encoded GPCR chemokine receptor homologs, products of the US27, US28, UL33 and UL78 genes. G protein-coupled receptors (GPCR) are the largest family of cell surface proteins, found in organisms from yeast to humans. In this research, phylogenetic analysis was used to investigate the origins of the US27 and US28 genes, which are adjacent in the viral genome. The results indicate that …
Darwinian Sex Roles Confirmed Across The Animal Kingdom, Tim Janicke, Ines K. Häderer, Marc J. Lajeunesse, Nils Anthes
Darwinian Sex Roles Confirmed Across The Animal Kingdom, Tim Janicke, Ines K. Häderer, Marc J. Lajeunesse, Nils Anthes
Integrative Biology Faculty and Staff Publications
Since Darwin's conception of sexual selection theory, scientists have struggled to identify the evolutionary forces underlying the pervasive differences between male and female behavior, morphology, and physiology. The Darwin-Bateman paradigm predicts that anisogamy imposes stronger sexual selection on males, which, in turn, drives the evolution of conventional sex roles in terms of female-biased parental care and male-biased sexual dimorphism. Although this paradigm forms the cornerstone of modern sexual selection theory, it still remains untested across the animal tree of life. This lack of evidence has promoted the rise of alternative hypotheses arguing that sex differences are entirely driven by environmental …
Phylogenetics And Molecular Evolution Of Highly Eusocial Wasps, Federico Lopez-Osorio
Phylogenetics And Molecular Evolution Of Highly Eusocial Wasps, Federico Lopez-Osorio
Graduate College Dissertations and Theses
Societies where workers sacrifice their own reproduction and cooperatively nurture the offspring of a reproductive queen caste have originated repeatedly across the Tree of Life. The attainment of such reproductive division of labor enabled the evolution of remarkable diversity in development, behavior, and social organization in the Hymenoptera (ants, bees, and wasps). Wasps of the family Vespidae exhibit a gamut of social levels, ranging from solitary to highly social behavior. The highly social yellowjackets and hornets (Vespinae) have well developed differences in form and function between queens and workers, large colony sizes, and intricate nest architecture. Moreover, certain socially parasitic …
Evolution Of The Vertebrate Claudin Gene Family: Insights From A Basal Vertebrate, The Sea Lamprey, Christian Mukendi, Nicholas Dean, Rushil Lala, Jeramiah J. Smith, Marianne E Bronner, Natalya V. Nikitina
Evolution Of The Vertebrate Claudin Gene Family: Insights From A Basal Vertebrate, The Sea Lamprey, Christian Mukendi, Nicholas Dean, Rushil Lala, Jeramiah J. Smith, Marianne E Bronner, Natalya V. Nikitina
Biology Faculty Publications
Claudins are major constituents of tight junctions, contributing both to their intercellular sealing and selective permeability properties. While claudins and claudin-like molecules are present in some invertebrates, the association of claudins with tight junctions has been conclusively documented only in vertebrates. Here we report the sequencing, phylogenetic analysis and comprehensive spatiotemporal expression analysis of the entire claudin gene family in the basal extant vertebrate, the sea lamprey. Our results demonstrate that clear orthologues to about half of all mammalian claudins are present in the lamprey, suggesting that at least one round of whole genome duplication contributed to the diversification of …
Isolation And Characterization Of Microbial Community Associated With Diadumene Lineata, The Orange-Striped Sea Anemone, Tiffany Lin, Andrew Weir
Isolation And Characterization Of Microbial Community Associated With Diadumene Lineata, The Orange-Striped Sea Anemone, Tiffany Lin, Andrew Weir
Student and Faculty Research Days
The orange-striped sea anemone, Diadumene lineata, is a marine invertebrate that can be found in the Northern Hemisphere. Distribution of Diadumene lineata ranges from Japan to the Gulf of Argentina. This invasive anemone originated from the Pacific Coast of Asia and serves as a host for a diverse microbial community including a photosynthetic alga. The epiphytic bacteria adhere to the outer surface as well as to the gastrovascular cavity of the host. The microbial community associated with Diadumene lineata is relatively unknown. This study attempted to isolate and identify bacteria commonly associated with this invasive marine invertebrate. Diadumene lineata was …
Identification And Characterisation Of Mlo Genes In Pea (Pisum Sativum L.)Vis-À-Vis Validation Of Mlo Gene-Specific Markers, Chinmayee Mohapatra, Ramesh Chand, Vinay Kumar Singh, Anil Kumar Singh, Chanda Kushwaha
Identification And Characterisation Of Mlo Genes In Pea (Pisum Sativum L.)Vis-À-Vis Validation Of Mlo Gene-Specific Markers, Chinmayee Mohapatra, Ramesh Chand, Vinay Kumar Singh, Anil Kumar Singh, Chanda Kushwaha
Turkish Journal of Biology
Pea is infected by a number of pathogens, and among them powdery mildew (PM) caused by Erysiphe pisi is an important fungal disease. This work was undertaken in silico to characterise the identified PM resistant genes of pea and design specific primers to be used in marker-assisted selection (MAS) of resistant and susceptible pea genotypes. Mlo gene sequences of A. thaliana and O. sativa were retrieved from different databases and used for a homology search of P. sativum EST databases. Each identified gene was used for a similarity search and phylogenetic classification with different crops. Four gene-specific primers were designed …
A Comprehensive Benchmarking Study Of Protocols And Sequencing Platforms For 16s Rrna Community Profiling, Rosalinda D’Amore, Umer Zeeshan Ijaz, Melanie Schirmer, John G. Kenny, Richard Gregory, Alistair C. Darby, Migun Shakya
A Comprehensive Benchmarking Study Of Protocols And Sequencing Platforms For 16s Rrna Community Profiling, Rosalinda D’Amore, Umer Zeeshan Ijaz, Melanie Schirmer, John G. Kenny, Richard Gregory, Alistair C. Darby, Migun Shakya
Dartmouth Scholarship
In the last 5 years, the rapid pace of innovations and improvements in sequencing technologies has completely changed the landscape of metagenomic and metagenetic experiments. Therefore, it is critical to benchmark the various methodologies for interrogating the composition of microbial communities, so that we can assess their strengths and limitations. The most common phylogenetic marker for microbial community diversity studies is the 16S ribosomal RNA gene and in the last 10 years the field has moved from sequencing a small number of amplicons and samples to more complex studies where thousands of samples and multiple different gene regions are interrogated. …
Two Complete Mitochondrial Genomes From Praticolella Mexicana Perez, 2011 (Polygyridae) And Gene Order Evolution In Helicoidea (Mollusca, Gastropoda), Russell L. Minton, Marco A. Martinez Cruz, Mark L. Farman, Kathryn E. Perez
Two Complete Mitochondrial Genomes From Praticolella Mexicana Perez, 2011 (Polygyridae) And Gene Order Evolution In Helicoidea (Mollusca, Gastropoda), Russell L. Minton, Marco A. Martinez Cruz, Mark L. Farman, Kathryn E. Perez
Biology Faculty Publications and Presentations
Helicoidea is a diverse group of land snails with a global distribution. While much is known regarding the relationships of helicoid taxa, comparatively little is known about the evolution of the mitochondrial genome in the superfamily. We sequenced two complete mitochondrial genomes from Praticolella mexicana Perez, 2011 representing the first such data from the helicoid family Polygyridae, and used them in an evolutionary analysis of mitogenomic gene order. We found the mitochondrial genome of P. mexicana to be 14,008 bp in size, possessing the typical 37 metazoan genes. Multiple alternate stop codons are used, as are incomplete stop codons. Mitogenome …