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

Life Sciences Commons

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

Articles 1 - 9 of 9

Full-Text Articles in Life Sciences

Behavioral And Chemical Ecology Of Marine Organisms With Respect To Tetrodotoxin, Becky L. Williams Feb 2010

Behavioral And Chemical Ecology Of Marine Organisms With Respect To Tetrodotoxin, Becky L. Williams

Biology Faculty Publications

The behavioral and chemical ecology of marine organisms that possess tetrodotoxin (TTX) has not been comprehensively reviewed in one work to date. The evidence for TTX as an antipredator defense, as venom, as a sex pheromone, and as an attractant for TTX-sequestering organisms is discussed. Little is known about the adaptive value of TTX in microbial producers; thus, I focus on what is known about metazoans that are purported to accumulate TTX through diet or symbioses. Much of what has been proposed is inferred based on the anatomical distribution of TTX. Direct empirical tests of these hypotheses are absent in …


The Evolution Of Chloroplast Genome Structure In Ferns, Paul G. Wolf, J. M. Roper, A. M. Duffy Jan 2010

The Evolution Of Chloroplast Genome Structure In Ferns, Paul G. Wolf, J. M. Roper, A. M. Duffy

Biology Faculty Publications

The plastid genome (plastome) is a rich source of phylogenetic and other comparative data in plants. Most land plants possess a plastome of similar structure. However, in a major group of plants, the ferns, a unique plastome structure has evolved. The gene order in ferns has been explained by a series of genomic inversions relative to the plastome organization of seed plants. Here, we examine for the first time the structure of the plastome across fern phylogeny. We used a PCR-based strategy to map and partially sequence plastomes. We found that a pair of partially overlapping inversions in the region …


Chloroplast Genome Sequence Of The Moss Torula Ruralis: Gene Content, Polymorphism, And Structural Arrangement Relative To Other Green Plant Chloroplast Genomes, M. J. Oliver, A. G. Murdock, B. D. Mishler, J. V. Kuehl, J. L. Boore, D. F. Mandoli, K. D. E. Everett, Paul G. Wolf, A. M. Duffy, K. G. Karol Jan 2010

Chloroplast Genome Sequence Of The Moss Torula Ruralis: Gene Content, Polymorphism, And Structural Arrangement Relative To Other Green Plant Chloroplast Genomes, M. J. Oliver, A. G. Murdock, B. D. Mishler, J. V. Kuehl, J. L. Boore, D. F. Mandoli, K. D. E. Everett, Paul G. Wolf, A. M. Duffy, K. G. Karol

Biology Faculty Publications

Background Tortula ruralis, a widely distributed species in the moss family Pottiaceae, is increasingly used as a model organism for the study of desiccation tolerance and mechanisms of cellular repair. In this paper, we present the chloroplast genome sequence of T. ruralis, only the second published chloroplast genome for a moss, and the first for a vegetatively desiccation-tolerant plant. Results The Tortula chloroplast genome is ~123,500 bp, and differs in a number of ways from that of Physcomitrella patens, the first published moss chloroplast genome. For example, Tortula lacks the ~71 kb inversion found in the large single copy region …


Complete Plastome Sequences Of Equisetum Arvense And Isoetes Flaccida: Implications For Phylogeny And Plastid Genome Evolution Of Early Land Plant Lineages, K. G. Karol, K. Arumuganthan, J. L. Boore, A. M. Duffy, K. D. E. Everett, J. D. Hall, S. K. Hansen, J. V. Mandoli, D. F. Mandoli, B. D. Mishler, R. G. Olmstead, K. S. Renzaglia, Paul G. Wolf Jan 2010

Complete Plastome Sequences Of Equisetum Arvense And Isoetes Flaccida: Implications For Phylogeny And Plastid Genome Evolution Of Early Land Plant Lineages, K. G. Karol, K. Arumuganthan, J. L. Boore, A. M. Duffy, K. D. E. Everett, J. D. Hall, S. K. Hansen, J. V. Mandoli, D. F. Mandoli, B. D. Mishler, R. G. Olmstead, K. S. Renzaglia, Paul G. Wolf

Biology Faculty Publications

Background Despite considerable progress in our understanding of land plant phylogeny, several nodes in the green tree of life remain poorly resolved. Furthermore, the bulk of currently available data come from only a subset of major land plant clades. Here we examine early land plant evolution using complete plastome sequences including two previously unexamined and phylogenetically critical lineages. To better understand the evolution of land plants and their plastomes, we examined aligned nucleotide sequences, indels, gene and nucleotide composition, inversions, and gene order at the boundaries of the inverted repeats. Results We present the plastome sequences of Equisetum arvense, a …


Unfurling Fern Biology In The Genomics Age, M. S. Barker, Paul G. Wolf Jan 2010

Unfurling Fern Biology In The Genomics Age, M. S. Barker, Paul G. Wolf

Biology Faculty Publications

Twenty-first century technology is addressing many of the questions posed by 20th-century biology. Although the new approaches, especially those involving genomic data and bioinformatic tools, were first applied to model organisms, they are now stretching across the tree of life. Here, we review some recent revelations in the ferns. We first examine how DNA sequence data have contributed to our understanding of fern phylogeny. We then address evolution of the fern plastid genome, including reports of high levels of RNA editing. Recent studies are also shedding light on the evolution of fern nuclear genomes. Initial analyses of genomic data suggest …


Teaching Species, Mark W. Ellis, Paul G. Wolf Jan 2010

Teaching Species, Mark W. Ellis, Paul G. Wolf

Biology Faculty Publications

A clear understanding of the term "species" is fundamental to the subject of evolution. However, introductory textbooks often fail to address this topic until one of the later chapters, after having used the term species in all preceding chapters. Furthermore, definitions of terms critical to a clear understanding of this subject are often vague or absent in chapters on species concepts. We feel the popular notion of a "species problem" has been unnecessarily inflated by this less-than-effective educational approach. Clearly addressing this essential subject at the beginning of a course on evolution will prepare students to learn the details and …


The Combined Influence Of The Local Environment Andregional Enrichment On Bird Species Richness, Ethan P. White, A. H. Hurlbert Jan 2010

The Combined Influence Of The Local Environment Andregional Enrichment On Bird Species Richness, Ethan P. White, A. H. Hurlbert

Biology Faculty Publications

It is generally accepted that local species richness at a site reflects the combined influence of local and regional processes. However, most empirical studies evaluate the influence of either local environmental variables or regional enrichment but not both simultaneously. Here we demonstrate the importance of combining these processes to understand continental scale richness patterns in breeding birds. We show that neither regional enrichment nor the local environment in isolation is sufficient to characterize observed patterns of species richness. Combining both sets of variables into a single model results in improved model fit and the removal of residual spatial autocorrelation. At …


Loss Of Foundation Species Increases Population Growth Of Exotic Forbs In Sagebrush Steppe, J S. Prevey, M J. Germino, Nancy J. Huntly Jan 2010

Loss Of Foundation Species Increases Population Growth Of Exotic Forbs In Sagebrush Steppe, J S. Prevey, M J. Germino, Nancy J. Huntly

Biology Faculty Publications

The invasion and spread of exotic plants following land disturbance threatens semiarid ecosystems. In sagebrush steppe, soil water is scarce and is partitioned between deeprooted perennial shrubs and shallower-rooted native forbs and grasses. Disturbances commonly remove shrubs, leaving grass-dominated communities, and may allow for the exploitation of water resources by the many species of invasive, tap-rooted forbs that are increasingly successful in this habitat. We hypothesized that exotic forb populations would benefit from increased soil water made available by removal of sagebrush, a foundation species capable of deep-rooting, in semiarid shrub-steppe ecosystems. To test this hypothesis, we used periodic matrix …


Seasonal Patterns Of Arthropod Diversity And Abundance On Big Sagebrush, Artemisia Trientata, M P. Stanford, Nancy J. Huntly Jan 2010

Seasonal Patterns Of Arthropod Diversity And Abundance On Big Sagebrush, Artemisia Trientata, M P. Stanford, Nancy J. Huntly

Biology Faculty Publications

The sagebrush biotype is the largest in the western United States. This vast sagebrush community is thought to harbor equally vast and diverse arthropod communities, but these remain little explored. Our objective was to examine the diversity, abundance, and seasonal phenology of arthropod taxa found on the dominant shrub of the sagebrush ecosystem, big sagebrush (Artemisia tridentata). We wanted to improve understanding of this little-studied arthropod assemblage that may play significant roles in the dynamics of sagebrush populations and the sagebrush ecosystem. We sampled free-living and gall-forming arthropods from a stratified random sample of sagebrush plants at the Barton Road …