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A Comparative Analysis Of The Relative Water Content Of The Pollen Of Early Diverging Angiosperms, Andrew Robert Moffatt 2012 University of Tennessee, Knoxville

A Comparative Analysis Of The Relative Water Content Of The Pollen Of Early Diverging Angiosperms, Andrew Robert Moffatt

Chancellor’s Honors Program Projects

No abstract provided.


Ribosomal Rna Gene-Based And Multigene Phylogenies Of Smittium (Harpellales) And Allies—Toward Unraveling Relationships Among Early-Diverging Fungi, Yan Wang 2012 Boise State University

Ribosomal Rna Gene-Based And Multigene Phylogenies Of Smittium (Harpellales) And Allies—Toward Unraveling Relationships Among Early-Diverging Fungi, Yan Wang

Boise State University Theses and Dissertations

Smittium is one of the oldest members of the Harpellales, a group commonly referred to as the “gut fungi”. Gut fungi are endosymbiotic microorganisms that live in the digestive tracts of various Arthropods, worldwide. During the 75 years since the first species, Smittium arvernense, was described, Smittium has increased in number and now includes 81 species. Research on this genus has also helped to advance our understanding of the gut fungi, by serving as a “model” for laboratory studies of the fungal trichomycetes. Many isolates of Smittium have been used for ultrastructural, physiological, host feeding, serological, as well as …


The Effects Of Nutrient Limitation And Cyanophage On Heterotrophic Microbial Diversity, Claire Elyse Campbell 2012 University of Tennessee, Knoxville

The Effects Of Nutrient Limitation And Cyanophage On Heterotrophic Microbial Diversity, Claire Elyse Campbell

Masters Theses

Marine viruses are critically important in the regulation of biogeochemical cycles and host microbial communities. In this study, we tested whether the indirect effects of virus predation on a phototroph (i.e., Synechococcus) affected the composition of co-occurring heterotrophic bacteria under nitrogen and phosphorus limitation in long-term chemostat experiments. Using 454 Titanium barcoded pyrosequencing of the 16S rRNA gene, microbial diversity and technical (i.e., sequencing) reproducibility were assessed for nine individual chemostats across five different time points. A total of 325,142 reads were obtained; 194,778 high-quality, non-cyanobacterial sequences were assigned to 110 OTUs. Our results show high reproducibility …


Introduced Chinook Salmon (Oncorhynchus Tshawytscha) In Lake Huron: Do They Spawn At The Right Time?, Meghan T. Gerson 2012 The University of Western Ontario

Introduced Chinook Salmon (Oncorhynchus Tshawytscha) In Lake Huron: Do They Spawn At The Right Time?, Meghan T. Gerson

Electronic Thesis and Dissertation Repository

Chinook salmon (Oncorhynchus tshawytscha), following their introduction to the Great Lakes, have successfully colonized many tributaries. Under the hypothesis that colonization success is facilitated by intrinsic factors (i.e., preadaptation), I predicted that patterns of reproductive timing in an introduced population would show similarities with those in their native range. To test this prediction, attributes of reproductive timing were characterized in Chinook salmon from the Sydenham River, Ontario. In their native range, female Chinook salmon exhibit a seasonal decline in reproductive lifespan, a decline in fat stores, low egg retention at death (< 0.5%), and spawning at temperatures below 12.8°C. In contrast, Sydenham River Chinook salmon showed no seasonal decline in reproductive lifespan or fat stores and nineteen of twenty females had egg retention greater or equal to 0.5%. Also, many individuals (30%) spawned when water temperatures exceeded 12.8°C. Thus, individuals do not appear to be pre-adapted in this system.


From A Rodent To A Rhetorician: An Ideological Analysis Of George Alexander Kennedy's Comparative Rhetoric, James Begley 2012 Liberty University

From A Rodent To A Rhetorician: An Ideological Analysis Of George Alexander Kennedy's Comparative Rhetoric, James Begley

Masters Theses

George Alexander Kennedy, a professor of classics at the University of North Carolina at Chapel Hill, has given birth to a new understanding of rhetorical studies: he argues for the evolution of rhetoric from animals to humans. Using Sonja Foss's methodology of "ideological criticism," this thesis examined Kennedy's case as presented in his book, Comparative Rhetoric: an Historical and Cross-Cultural Introduction. This study discovered that the book was heavily influenced by a secular, pro-evolutionary ideology which dually contributed to its selective use of scientific evidences and production of inconsistent arguments. Evaluated on the basis of Biblical principles, this thesis concluded …


Gene Duplication And The Evolution Of Hemoglobin Isoform Differentiation In Birds, Michael T. Grispo 2012 University of Nebraska-Lincoln

Gene Duplication And The Evolution Of Hemoglobin Isoform Differentiation In Birds, Michael T. Grispo

School of Biological Sciences: Dissertations, Theses, and Student Research

The majority of bird species co-express two functionally distinct hemoglobin (Hb) isoforms in definitive erythrocytes: HbA (the major adult Hb isoform, with α-chain subunits encoded by the αA-globin gene) and HbD (the minor adult Hb isoform, with α-chain subunits encoded by the αD-globin gene). The αD-globin gene originated via tandem duplication of an embryonic α-like globin gene in the stem lineage of tetrapod vertebrates, which suggests the possibility that functional differentiation between the HbA and HbD isoforms may be attributable to a retained ancestral character state in HbD that harkens back to a primordial, …


The Behavioural And Sensory Ecology Of Agaronia Propatula (Caenogastropoda, Olividae), A Swash-Surfing Predator On Sandy Beaches Of The Panamic Faunal Province, Ariel Cyrus, Samantha Rupert, Amy Silva, Monika Graf, Jeremy Rappaport, Frank Paladino, Winfried Peters 2012 Indiana University - Purdue University Fort Wayne

The Behavioural And Sensory Ecology Of Agaronia Propatula (Caenogastropoda, Olividae), A Swash-Surfing Predator On Sandy Beaches Of The Panamic Faunal Province, Ariel Cyrus, Samantha Rupert, Amy Silva, Monika Graf, Jeremy Rappaport, Frank Paladino, Winfried Peters

Winfried S. Peters

The genus Agaronia includes dominant predators in the eulittoral zone of dissipative sandy beaches of the tropical Eastern Pacific, which show specific adaptations to this environment such as swash-surfing locomotion. We studied A. propatula in its natural habitat in El Salvador and Costa Rica, and performed field experiments to obtain insights into its ecology, behaviour and sensory physiology. Agaronia propatula is not attracted by carrion and preys mostly on the ubiquitous beach snail Olivella semistriata. This, however, reflects community composition rather than prey specialization; A. propatula is an investigative hunter and will, quite literally, attack everything that moves (with …


The Mirage Of A Space Between Nature And Nurture By Evelyn Fox Keller (Review), David Depew 2012 University of Iowa

The Mirage Of A Space Between Nature And Nurture By Evelyn Fox Keller (Review), David Depew

David J Depew

No abstract provided.


On Characterizing Adaptive Events Unique To Modern Humans, Jessica Crisci, Alex Wong, Jeffrey Good, Jeffrey Jensen 2012 University of Massachusetts Medical School

On Characterizing Adaptive Events Unique To Modern Humans, Jessica Crisci, Alex Wong, Jeffrey Good, Jeffrey Jensen

Jessica L Crisci

Ever since the first draft of the human genome was completed in 2001 there has been increased interest in identifying genetic changes that are uniquely human, which could account for our distinct morphological and cognitive capabilities with respect to other apes. Recently, draft sequences of two extinct hominin genomes, a Neanderthal and Denisovan, have been released. These two genomes provide a much greater resolution to identify human-specific genetic differences than the chimpanzee, our closest extant relative. The Neanderthal genome paper presented a list of regions putatively targeted by positive selection around the time of the human-Neanderthal split. We here seek …


Some Biogeographers, Evolutionists And Ecologists: Chrono-Biographical Sketches, Charles H. Smith, Joshua Woleben, Carubie Rodgers 2012 Western Kentucky University

Some Biogeographers, Evolutionists And Ecologists: Chrono-Biographical Sketches, Charles H. Smith, Joshua Woleben, Carubie Rodgers

DLPS Faculty Publications

Each name in the following list of naturalists is linked to a corresponding capsule "chrono-biographical" sketch of that individual prepared by the authors. Coverage extends from approximately 1950 backward in time as far as the eighteenth century; figures from all over the world are included (though there is admittedly a decided Anglo-American bias). The target subject here is biogeography, but this being a broad field there are many persons on the list who are better known as climatologists, zoologists, botanists, ecologists, oceanographers, paleontologists, etc.--in other words, who made their main reputations in cognate disciplines.

This service has been set up …


I Also Survived A Debate With A Creationist (With Reflections On The Perils Of Democratic Information), Kelly C. Smith 2012 Clemson University

I Also Survived A Debate With A Creationist (With Reflections On The Perils Of Democratic Information), Kelly C. Smith

Publications

A personal narrative is presented which explores the author's experience of debating with a creationist.


Runx2 Tandem Repeats And The Evolution Of Facial Length In Placental Mammals, Jason M. Kamilar, Marie A. Pointer, Vera Warmuth, Stephen G.B. Chester, Frédéric Delsuc, Nicholas I. Mundy, Robert J. Asher, Brenda J. Bradley 2012 University of Massachusetts Amherst

Runx2 Tandem Repeats And The Evolution Of Facial Length In Placental Mammals, Jason M. Kamilar, Marie A. Pointer, Vera Warmuth, Stephen G.B. Chester, Frédéric Delsuc, Nicholas I. Mundy, Robert J. Asher, Brenda J. Bradley

Anthropology Department Faculty Publication Series

Background

When simple sequence repeats are integrated into functional genes, they can potentially act as evolutionary ‘tuning knobs’, supplying abundant genetic variation with minimal risk of pleiotropic deleterious effects. The genetic basis of variation in facial shape and length represents a possible example of this phenomenon. Runt-related transcription factor 2 (RUNX2), which is involved in osteoblast differentiation, contains a functionally-important tandem repeat of glutamine and alanine amino acids. The ratio of glutamines to alanines (the QA ratio) in this protein seemingly influences the regulation of bone development. Notably, in domestic breeds of dog, and in carnivorans in general, the ratio …


A New Species Of Frog (Strabomantidae: Pristimantis) From Peru With Comments On Its Ectoparasites (Acari: Trombiculidae), Alan W. Brus 2012 Illinois Wesleyan University

A New Species Of Frog (Strabomantidae: Pristimantis) From Peru With Comments On Its Ectoparasites (Acari: Trombiculidae), Alan W. Brus

Honors Projects

In South America, frogs of the genus Pristimantis are diverse and can be found from lowland forests to elevations of about 4000 m in the Andes. The 444 known species of Pristimantis belong to 16 species groups. One of these groups is the Pristimantis orestes Group, the 14 members of which inhabit the páramo, puna, and upper montane forests in southern Ecuador (3 species) and Peru (11 species). Species of the Pristimantis orestes Group are characterized by having snout-vent lengths ranging from 18.0 to 29.4 mm, short robust bodies, relatively short snouts, narrow digital discs, and areolate ventral skin. Some …


Alfred Russel Wallace & The Notion Of Final Causes In Evolution, Charles H. Smith 2012 Western Kentucky University

Alfred Russel Wallace & The Notion Of Final Causes In Evolution, Charles H. Smith

Faculty/Staff Personal Papers

The methodology of Empiricism, with its emphasis on linking efficient causes to specific effects, has now dominated science for over three hundred years, and to productive end. Another of the other original Aristotelian concepts of causation, however, the notion of “final causes,” has largely been ignored by the scientific community – perhaps because it seems to necessitate teleology, or even direct interventions (“first causes”) from outside of the realm of natural process.

The most famous example of the operation of final causes comes down from ancient times. The sculptor is described as imagining what his completed form will look like, …


Natural Selection: A Concept In Need Of Some Evolution?, Charles H. Smith 2012 Western Kentucky University

Natural Selection: A Concept In Need Of Some Evolution?, Charles H. Smith

DLPS Faculty Publications

In some respects natural selection is a quite simple theory, arrived at through the logical integration of three propositions (the presence of variation within natural populations, an absolutely limited resources base, and procreation capacities exceeding mere replacement numbers) whose individual truths can hardly be denied. Its relation to the larger subject of evolution, however, remains problematic. It is suggested here that a scaling-down of the meaning of natural selection to “the elimination of the unfit,” as originally intended by Alfred Russel Wallace (1823-1913), might ultimately prove a more effective means of relating it to larger-scale, longer-term, evolutionary processes.


The Effect Of Historical Legacy On Adaptation: Do Closely Related Species Respond To The Environment In The Same Way?, Rachel Prunier, Kent E. Holsinger, Jane E. Carlson 2012 University of Connecticut - Storrs

The Effect Of Historical Legacy On Adaptation: Do Closely Related Species Respond To The Environment In The Same Way?, Rachel Prunier, Kent E. Holsinger, Jane E. Carlson

EEB Articles

The many documented examples of parallel and convergent evolution in similar environments are strong evidence for the role of natural selection in the evolution of trait variation. However, species may respond to selection in different ways; idiosyncrasies of their evolutionary history may affect how different species respond to the same selective pressure. To determine whether evolutionary history affects trait-environment associations in a recently diverged lineage, we investigated within-species trait-environment associations in the white proteas, a closely related monophyletic group. We first used MANOVAs to determine the relative importance of shared response to selection, evolutionary history, and unique responses to selection …


Salinity Preference Of Alaskan Threespine Stickleback: Test For Divergence In Halotaxis Between Ancestral And Landlocked Populations, David Fryxell, Eric T. Schultz 2012 University of Connecticut - Storrs

Salinity Preference Of Alaskan Threespine Stickleback: Test For Divergence In Halotaxis Between Ancestral And Landlocked Populations, David Fryxell, Eric T. Schultz

EEB Articles

Glacial retreat during the Pleistocene caused landlocking of anadromous Alaskan threespine stickleback, Gasterosteus aculeatus, furnishing a natural ‘experiment’ in osmoregulatory divergence. The objective of this study was to assess the effects of individual acclimation and population divergence on salinity preference. Full-sibling families of marine, anadromous, and freshwater-landlocked populations of stickleback were reared in common environments until 3 weeks post-hatch, then were split and acclimated to low or high salinity. At 6 to 8 weeks of age the six experimental groups were tested for salinity preference in a tank that offers fish a choice of compartments with different salinities arranged …


Evolution And The Expression Of Biases: Situational Value Changes The Endowment Effect In Chimpanzees, Owen D. Jones, Sarah F. Brosnan, Molly Gardner, Susan P. Lambeth, Steven J. Schapiro 2012 Georgia State University

Evolution And The Expression Of Biases: Situational Value Changes The Endowment Effect In Chimpanzees, Owen D. Jones, Sarah F. Brosnan, Molly Gardner, Susan P. Lambeth, Steven J. Schapiro

Vanderbilt Law School Faculty Publications

Cognitive and behavioral biases, which are widespread among humans, have recently been demonstrated in other primates, suggesting a common origin. Here we examine whether the expression of one shared bias, the endowment effect, varies as a function of context. We tested whether objects lacking inherent value elicited a stronger endowment effect (or preference for keeping the object) in a context in which the objects had immediate instrumental value for obtaining valuable resources (food). Chimpanzee subjects had opportunities to trade tools when food was not present, visible but unobtainable, and obtainable using the tools. We found that the endowment effect for …


Comparative Developmental Transcriptomics Of Echinoderms, Roy Vaughn 2012 University of South Florida

Comparative Developmental Transcriptomics Of Echinoderms, Roy Vaughn

USF Tampa Graduate Theses and Dissertations

The gastrula stage represents the point in development at which the three primary germ layers diverge. At this point the gene regulatory networks that specify the germ layers are established and the genes that define the differentiated states of the tissues have begun to be activated. These networks have been well characterized in sea urchins, but not in other echinoderms. Embryos of the brittle star Ophiocoma wendtii share a number of developmental features with sea urchin embryos, including the ingression of mesenchyme cells that give rise to an embryonic skeleton. Notable differences are that no micromeres are formed during cleavage …


Patterns Of Extinction Risk And Threat For Marine Vertebrates And Habitat-Forming Species In The Tropical Eastern Pacific, Beth A. Polidoro, T. Brooks, Kent E. Carpenter, G. J. Edgar, S Henderson, J. Sanciangco, D. R. Robertson 2012 Old Dominion University

Patterns Of Extinction Risk And Threat For Marine Vertebrates And Habitat-Forming Species In The Tropical Eastern Pacific, Beth A. Polidoro, T. Brooks, Kent E. Carpenter, G. J. Edgar, S Henderson, J. Sanciangco, D. R. Robertson

Biological Sciences Faculty Publications

Marine conservation activities around the globe are largely undertaken in the absence of comprehensive species-specific information. To address this gap, complete regional species assemblages of major marine taxa are being progressively assessed against the Categories and Criteria of the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. The present study is the first analysis of entire major components of the biota of a large marine biogeographic region conducted in the Tropical Eastern Pacific (TEP). It is based on recently completed IUCN Red List assessments for all known species of bony and cartilaginous shorefishes, corals, mangroves, …


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