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Full-Text Articles in Life Sciences

Protein Recycling In Bering Sea Algal Incubations, Eli K. Moore, H. Rodger Harvey, Jessica F. Faux, David R. Goodlett, Brook L. Nunn Nov 2014

Protein Recycling In Bering Sea Algal Incubations, Eli K. Moore, H. Rodger Harvey, Jessica F. Faux, David R. Goodlett, Brook L. Nunn

OES Faculty Publications

Protein present in phytoplankton represents a large fraction of the organic nitrogen and carbon transported from its synthesis in surface waters to marine sediments. Yet relatively little is known about the longevity of identifiable protein in situ, or the potential modifications to proteins that occur during bloom termination, protein recycling and degradation. To address this knowledge gap, diatom-dominated phytoplankton was collected during the Bering Sea spring blooms of 2009 and 2010, and incubated under darkness in separate shipboard degradation experiments spanning 11 and 53 d, respectively. In each experiment, the protein distribution was monited over time using shotgun proteomics, …


Predictors Patterns And Processes Of Extinction Risk In Porgies And Seabreams (Family: Sparidae), Mia Theresa B. Conteros Oct 2014

Predictors Patterns And Processes Of Extinction Risk In Porgies And Seabreams (Family: Sparidae), Mia Theresa B. Conteros

Biological Sciences Theses & Dissertations

A variety of human-induced changes are having profound impacts on the marine environment, and no area on the planet remains unaffected by the detrimental effects of our activities. These stressors can potentially lead to synergistic effects, causing accelerated biodiversity loss and diminished ecosystem functioning. Identification and understanding of the factors that drive species to heightened risk of extinction are important goals in conservation.

The Sparidae are commercially important and ecologically complex marine fishes; global extinction risk assessments using the IUCN Red List of Threatened Species methodology show that 9% (13 species) have increased vulnerability to population declines from intense fishing …


A Molecular Framework Phylogeny For Ptilotus (Amaranthaceae), Timothy A. Hammer Oct 2014

A Molecular Framework Phylogeny For Ptilotus (Amaranthaceae), Timothy A. Hammer

Biological Sciences Theses & Dissertations

Ptilotus (Amaranthaceae) is an Australian genus with over 100 species, most of which occur in arid Western Australia. Ptilotus has been a taxonomically difficult genus; despite rigorous morphological studies into the genus over many years, previous workers have found it difficult to delimit infrageneric groups due to inconsistent morphological variation. With the goal to establish a phylogenetic framework for the genus, 100 taxa were sampled, including 87 Ptilotus spp., and the ITS nrDNA and matK cpDNA were sequenced. The phylogeny was reconstructed using Bayesian, maximum likelihood and maximum parsimony analyses on separate and concatenated datasets. Morphological characters were assessed and …


The Role Of Chemical Attractants In The Use Of Tick Traps For Life Stages Of Tick Species Ixodes Scapularis, Dermacentor Variabilis And Amblyomma Maculatum, Pamela C. Kelman Oct 2014

The Role Of Chemical Attractants In The Use Of Tick Traps For Life Stages Of Tick Species Ixodes Scapularis, Dermacentor Variabilis And Amblyomma Maculatum, Pamela C. Kelman

Biological Sciences Theses & Dissertations

Amblyomma maculatum, Ixodes scapularis and Dermacentor variabilis are three of the hard-bodied ticks found in the United States. This study explored three aspects of the appetence process of these tick species: attraction, desiccation survival, and locomotive activity. The first portion of this work was to improve one of the standard methods used for collecting ticks from the environment, the tick trap. To determine the attractants needed to capture all life stages of the three chosen species of ticks in the field using tick traps, a series of experiments were conducted using laboratory-reared larval, nymphal and adult A. maculatum, I. scapularis …


A Comprehensive Evaluation Of C25 Highly Branched Isoprenoid Alkenes Of Marine Diatoms As Proxies For Sea Ice Extent In The Arctic Ocean, Tetiana Muniak Jul 2014

A Comprehensive Evaluation Of C25 Highly Branched Isoprenoid Alkenes Of Marine Diatoms As Proxies For Sea Ice Extent In The Arctic Ocean, Tetiana Muniak

OES Theses and Dissertations

Sea Ice extent is one of the major factors regulating carbon cycling and ecosystem function in the modern Arctic Ocean. It is an essential component of climate models and is crucial for the evaluation of various oceanographic processes that influence a particular region. Yet it is also one of the most difficult attributes of the ocean with respect to our ability for its accurate reconstruction from paleo records. The lack of the detailed records prior to satellite information has encouraged the development of new proxy records for the reconstruction of past

sea ice conditions. In recent years, a new monounsaturated …


Phylogeny And Biogeography Of The Family Haemulidae Based On A Multigene Approach, Millicent D. Sanciangco Jul 2014

Phylogeny And Biogeography Of The Family Haemulidae Based On A Multigene Approach, Millicent D. Sanciangco

Biological Sciences Theses & Dissertations

Haemulids are one of the most ecologically and commercially important groups of near-shore fishes. They are very diverse, with 145 putative species belonging to 18 genera. The phylogenetic relationships of the genera within the haemulids, however, are uncertain and the limits and relationships with other percomorphs are undefined.

Here, I present the first comprehensive phylogenetic hypothesis for the family based on a combined dataset of five genes (4731 bp; 16 genera, 56 species). Results show strong support for a monophyletic Haemulidae with the inclusion of the former inermiids. However, results of the analyses call into question the monophyly of a …


Spatial And Temporal Variability In Net Community Metabolism In The Middle Atlantic Bight, Georges Bank, And Gulf Of Maine: Observations Of Net Heterotrophic Phases In The Highly Productive Coastal Zone, Cory James Staryk Jul 2014

Spatial And Temporal Variability In Net Community Metabolism In The Middle Atlantic Bight, Georges Bank, And Gulf Of Maine: Observations Of Net Heterotrophic Phases In The Highly Productive Coastal Zone, Cory James Staryk

OES Theses and Dissertations

Net community metabolism (NCM), the balance between primary production and community respiration, was measured during two cruises, June 2011 and August 2012, in the Middle Atlantic Bight, Georges Bank and Gulf of Maine. Net heterotrophy was observed in Georges Bank and Gulf of Maine during the June 2011 cruise. During the August 2012 cruise, net heterotrophy was observed in the Middle Atlantic Bight and net autotrophy was observed in Georges Bank and the Gulf of Maine. Dark community respiration increased (DCR) with biomass and temperature. Gross community production (GCP) also increased with Chl a, bicarbonate uptake, and temperature. Net …


The Ecological Impact Of Casitas On Caribbean Spiny Lobster (Panulirus Argus) Populations In The Florida Keys, Fl, (Usa), Benjamin C. Gutzler Jul 2014

The Ecological Impact Of Casitas On Caribbean Spiny Lobster (Panulirus Argus) Populations In The Florida Keys, Fl, (Usa), Benjamin C. Gutzler

Biological Sciences Theses & Dissertations

Casitas are artificial structures placed on the seabed by fishermen to aggregate Caribbean spiny lobsters (Panulirus argus) for ease of capture. Some researchers suggest that they may also enhance lobster populations in shelter-limited environments. Conversely, aggregation of lobsters within casitas may be detrimental to the population if the nutritional condition or mortality of lobsters is poorer in casitas than in natural shelters. Small juvenile lobsters may be at particular risk because their foraging range is smaller and they are more readily preyed upon than larger lobsters. If so, then casitas placed in lobster nurseries may function as "ecological traps"; wherein …


Determination Of The Ecological Condition Of Benthic Communities Affected By Polycyclic Aromatic Hydrocarbons In The Elizabeth River, Chesapeake Bay, Usa, Adam M. Webb Apr 2014

Determination Of The Ecological Condition Of Benthic Communities Affected By Polycyclic Aromatic Hydrocarbons In The Elizabeth River, Chesapeake Bay, Usa, Adam M. Webb

Biological Sciences Theses & Dissertations

The Southern Branch of the Elizabeth River, a tributary of Chesapeake Bay, has historically been polluted with hydrocarbon based industrial by-products. My study compared benthic community condition from two locations in the Southern Branch: the subtidal region near Money Point, historically affected by pollution of polycyclic aromatic hydrocarbons (PAHs), to a subtidal region near Blows Creek on the opposite shore that is putatively designated as unimpacted by P AH contamination. Samples from both study sites in the Southern Branch were compared to the benthic community condition of samples from the same habitat type designations collected as part of the Chesapeake …


Benthic And Planktonic Microalgal Community Structure And Primary Productivity In Lower Chesapeake Bay, Matthew Reginald Semcheski Apr 2014

Benthic And Planktonic Microalgal Community Structure And Primary Productivity In Lower Chesapeake Bay, Matthew Reginald Semcheski

Biological Sciences Theses & Dissertations

Microalgal populations are trophically important to a variety of micro- and macroheterotrophs in marine and estuarine systems. In Chesapeake Bay, microalgae facilitate the survival and development of ecologically and economically relevant fauna, including shellfish and finfish populations. While regarded as significant components of coastal environments, microphytobenthic communities are historically understudied. In Chesapeake Bay, the importance of phytoplankton to the ecosystem is understood, but the contribution of microphytobenthos remains unclear. This project surveys intertidal microphytobenthic communities, in relation to phytoplankton communities, around lower Chesapeake Bay describing the taxonomic makeup of these populations, coupled with quantification of cell abundance, biomass, and primary …


Host Behavior Alters Spiny Lobster-Viral Disease Dynamics: A Simulation Study, Thomas W. Dolan Iii, Mark J. Butler Iv, Jeffrey D. Shields Jan 2014

Host Behavior Alters Spiny Lobster-Viral Disease Dynamics: A Simulation Study, Thomas W. Dolan Iii, Mark J. Butler Iv, Jeffrey D. Shields

Biological Sciences Faculty Publications

Social behavior confers numerous benefits to animals but also risks, among them an increase in the spread of pathogenic diseases. We examined the trade-off between risk of predation and disease transmission under different scenarios of host spatial structure and disease avoidance behavior using a spatially explicit, individual-based model of the host pathogen interaction between juvenile Caribbean spiny lobster (Panulirus argus) and Panulirus argus Virus 1 (PaV1). Spiny lobsters are normally social but modify their behavior to avoid diseased conspecifics, a potentially effective means of reducing transmission but one rarely observed in the wild. We found that without lobster avoidance of …


Phylogeography Unplugged: Comparative Surveys In The Genomic Era, Brian W. Bowen, Kartik Shanker, Nina Yasuda, Maria Celia Malay, Sophie Von Der Heyden, Gustav Paulay, Luiz A. Rocha, Kimberly A. Selkoe, Paul H. Barber, Suzanne T. Williams, Harilaos A. Lessios, Eric D. Crandall, Giacomo Bernardi, Christopher P. Meyer, Kent E. Carpenter, Robert J. Toonen Jan 2014

Phylogeography Unplugged: Comparative Surveys In The Genomic Era, Brian W. Bowen, Kartik Shanker, Nina Yasuda, Maria Celia Malay, Sophie Von Der Heyden, Gustav Paulay, Luiz A. Rocha, Kimberly A. Selkoe, Paul H. Barber, Suzanne T. Williams, Harilaos A. Lessios, Eric D. Crandall, Giacomo Bernardi, Christopher P. Meyer, Kent E. Carpenter, Robert J. Toonen

Biological Sciences Faculty Publications

In March 2012, the authors met at the National Evolutionary Synthesis Center (NESCent) in Durham, North Carolina, USA, to discuss approaches and cooperative ventures in Indo-Pacific phylogeography. The group emerged with a series of findings: (1) Marine population structure is complex, but single locus mtDNA studies continue to provide powerful first assessment of phylogeographic patterns. (2) These patterns gain greater significance/power when resolved in a diversity of taxa. New analytical tools are emerging to address these analyses with multi-taxon approaches. (3) Genome-wide analyses are warranted if selection is indicated by surveys of standard markers. Such indicators can include discordance between …


A Coupled Geochemical And Biogeochemical Approach To Characterize The Bioreactivity Of Dissolved Organic Matter From A Headwater Stream, Rachel L. Sleighter, Rose M. Cory, Louis A. Kaplan, Hussain A.N. Abdulla, Patrick G. Hatcher Jan 2014

A Coupled Geochemical And Biogeochemical Approach To Characterize The Bioreactivity Of Dissolved Organic Matter From A Headwater Stream, Rachel L. Sleighter, Rose M. Cory, Louis A. Kaplan, Hussain A.N. Abdulla, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The bioreactivity or susceptibility of dissolved organic matter (DOM) to microbial degradation in streams and rivers is of critical importance to global change studies, but a comprehensive understanding of DOM bioreactivity has been elusive due, in part, to the stunningly diverse assemblages of organic molecules within DOM. We approach this problem by employing a range of techniques to characterize DOM as it flows through biofilm reactors: dissolved organic carbon (DOC) concentrations, excitation emission matrix spectroscopy (EEMs), and ultrahigh resolution mass spectrometry. The EEMs and mass spectral data were analyzed using a combination of multivariate statistical approaches. We found that 45% …


Modelling Cholera In Periodic Environments, Drew Posny, Jin Wang Jan 2014

Modelling Cholera In Periodic Environments, Drew Posny, Jin Wang

Mathematics & Statistics Faculty Publications

We propose a deterministic compartmental model for cholera dynamics in periodic environments. The model incorporates seasonal variation into a general formulation for the incidence (or, force of infection) and the pathogen concentration. The basic reproduction number of the periodic model is derived, based on which a careful analysis is conducted on the epidemic and endemic dynamics of cholera. Several specific examples are presented to demonstrate this general model, and numerical simulation results are used to validate the analytical prediction.


Extinction Risk And Conservation Of The World's Sharks And Rays, Nicholas K. Dulvy, Sarah L. Fowler, John A. Musick, Rachel D. Cavanagh, Peter M. Kyne, Lucy R. Harrison, John K. Carlson, Lindsay N. K. Davidson, Sonja V. Fordham, Malcolm P. Francis, Caroline M. Pollock, Colin A. Simpfendorfer, George H. Burgess, Kent E. Carpenter, Leonard J. V. Compagno, David A. Ebert, Claudine Gibson, Michelle R. Heupel, Suzanne R. Livingstone, Jonnell C. Sanciangco, John D. Stevens, Sarah Valenti, William T. White Jan 2014

Extinction Risk And Conservation Of The World's Sharks And Rays, Nicholas K. Dulvy, Sarah L. Fowler, John A. Musick, Rachel D. Cavanagh, Peter M. Kyne, Lucy R. Harrison, John K. Carlson, Lindsay N. K. Davidson, Sonja V. Fordham, Malcolm P. Francis, Caroline M. Pollock, Colin A. Simpfendorfer, George H. Burgess, Kent E. Carpenter, Leonard J. V. Compagno, David A. Ebert, Claudine Gibson, Michelle R. Heupel, Suzanne R. Livingstone, Jonnell C. Sanciangco, John D. Stevens, Sarah Valenti, William T. White

Biological Sciences Faculty Publications

The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes-sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other …


Concordant Phylogenetic Patterns Inferred From Mitochondrial And Microsatellite Dna In The Giant Clam Tridacna Crocea, Timery S. Deboer, Ma Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toba, Paul H. Barber Jan 2014

Concordant Phylogenetic Patterns Inferred From Mitochondrial And Microsatellite Dna In The Giant Clam Tridacna Crocea, Timery S. Deboer, Ma Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toba, Paul H. Barber

Biological Sciences Faculty Publications

The boring giant clam, Tridacna crocea Lamarck, 1819, is a CITES-listed bivalve that is declining due to overharvest and environmental degradation. Previous molecular studies in the Coral Triangle using mitochondrial DNA indicated the presence of deep phylogenetic divergence and strong phylogeographic structure across this region, suggesting the possibility of multiple cryptic species. In the present study, we compare data from non-recombining mitochondrial (mtDNA; cytochrome oxidase subunit 1, COI) and eight microsatellite loci to better understand patterns of genetic structure and species boundaries in T. crocea populations across Indonesia and the Philippines. Microsatellite loci and mtDNA data from 618 individuals representing …


Effects Of Predation Upon The Long-Spined Sea Urchin Diadema Antillarum By The Spotted Spiny Lobster Panulirus Guttatus, Meredith D. Kintzing, Mark J. Butler Iv Jan 2014

Effects Of Predation Upon The Long-Spined Sea Urchin Diadema Antillarum By The Spotted Spiny Lobster Panulirus Guttatus, Meredith D. Kintzing, Mark J. Butler Iv

Biological Sciences Faculty Publications

Sea urchins, important herbivores in marine ecosystems, are strongly impacted by both the direct and indirect effects of predation, and the long-spined sea urchin Diadema antillarum is no exception. Once abundant on Caribbean coral reefs, D. antillarum populations were decimated by disease in the early 1980s, and only where their natural predators have been over-fished has D. antillarum recovery been observed. Spiny lobsters (Palinuridae) are predators of sea urchins, and although there are several species of spiny lobster in the Caribbean, only the spotted spiny lobster Panulirus guttatus is restricted to coral reefs where D. antillarum dwells. We investigated the …


Hidden Diversity In Sardines: Genetic And Morphological Evidence For Cryptic Species In The Goldstripe Sardinella, Sardinella Gibbosa (Bleeker, 1849), Rey C. Thomas, Demian A. Willette, Kent E. Carpenter, Mudjekeewis D. Santos Jan 2014

Hidden Diversity In Sardines: Genetic And Morphological Evidence For Cryptic Species In The Goldstripe Sardinella, Sardinella Gibbosa (Bleeker, 1849), Rey C. Thomas, Demian A. Willette, Kent E. Carpenter, Mudjekeewis D. Santos

Biological Sciences Faculty Publications

Cryptic species continue to be uncovered in many fish taxa, posing challenges for fisheries conservation and management. In Sardinella gibbosa, previous investigations revealed subtle intra-species variations, resulting in numerous synonyms and a controversial taxonomy for this sardine. Here, we tested for cryptic diversity within S. gibbosa using genetic data from two mitochondrial and one nuclear gene regions of 248 individuals of S. gibbosa, collected from eight locations across the Philippine archipelago. Deep genetic divergence and subsequent clustering was consistent across both mitochondrial and nuclear markers. Clade distribution is geographically limited: Clade 1 is widely distributed in the central Philippines, while …


Concordance Between Phylogeographic And Biogeographic Boundaries In The Coral Triangle: Conservation Implications Based On Comparative Analyses Of Multiple Giant Clam Species, Timery S. Deboer, Maria Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toha, Paul H. Barber Jan 2014

Concordance Between Phylogeographic And Biogeographic Boundaries In The Coral Triangle: Conservation Implications Based On Comparative Analyses Of Multiple Giant Clam Species, Timery S. Deboer, Maria Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toha, Paul H. Barber

Biological Sciences Faculty Publications

Marine habitats are in decline worldwide, precipitating a strong interest in marine conservation. The use of biogeographic data to designate ecoregions has had significant impacts on terrestrial conservation efforts. However, classification of marine environments into ecoregions has only become available in the last several years, based on biogeographic data supplemented by geomorphology, ocean currents, and water temperatures. Here we use a comparative phylogeographic approach to test for concordant phylogeographic patterns in three closely related species of Tridacna giant clams across the Coral Triangle, the most biodiverse marine region in the world and one of the most threatened. Data from a …


Wild Bees Preferentially Visit Rudbeckia Flower Heads With Exaggerated Ultraviolet Absorbing Floral Guides, Lisa Horth, Laura Campbell, Rebecca Bray Jan 2014

Wild Bees Preferentially Visit Rudbeckia Flower Heads With Exaggerated Ultraviolet Absorbing Floral Guides, Lisa Horth, Laura Campbell, Rebecca Bray

Biological Sciences Faculty Publications

Here, we report on the results of an experimental study that assessed the visitation frequency of wild bees to conspecific flowers with different sized floral guides. UV absorbent floral guides are ubiquitous in Angiosperms, yet surprisingly little is known about conspecific variation in these guides and very few studies have evaluated pollinator response to UV guide manipulation. This is true despite our rich understanding about learning and color preferences in bees. Historical dogma indicates that flower color serves as an important long-range visual signal allowing pollinators to detect the flowers, while floral guides function as close-range signals that direct pollinators …


Lineage-Specific Transcriptional Profiles Of Symbiodinium Spp. Unaltered By Heat Stress In A Coral Host, Daniel J. Barshis, Jason T. Ladner, Thomas A. Oliver, Stephen R. Palumbi Jan 2014

Lineage-Specific Transcriptional Profiles Of Symbiodinium Spp. Unaltered By Heat Stress In A Coral Host, Daniel J. Barshis, Jason T. Ladner, Thomas A. Oliver, Stephen R. Palumbi

Biological Sciences Faculty Publications

Dinoflagellates of the genus Symbiodinium form an endosymbiosis with reef building corals, in which photosynthetically derived nutrients comprise the majority of the coral energy budget. An extraordinary amount of functional and genetic diversity is contained within the coral-associated Symbiodinium, with some phylotypes (i.e., genotypic groupings), conferring enhanced stress tolerance to host corals. Recent advances in DNA sequencing technologies have enabled transcriptome-wide profiling of the stress response of the cnidarian coral host; however, a comprehensive understanding of the molecular response to stress of coral-associated Symbiodinium, as well as differences among physiologically susceptible and tolerant types, remains largely unexplored. Here, …


Developing Important Marine Mammal Area Criteria: Learning From Ecologically Or Biologically Significant Areas And Key Biodiversity Areas, Collenn M. Corrigan, Jeff A. Ardron, Mia T. Comeros-Raynal, Erich Hoyt, Giuseppe Notarbartolo Di Sciara, Kent E. Carpenter Jan 2014

Developing Important Marine Mammal Area Criteria: Learning From Ecologically Or Biologically Significant Areas And Key Biodiversity Areas, Collenn M. Corrigan, Jeff A. Ardron, Mia T. Comeros-Raynal, Erich Hoyt, Giuseppe Notarbartolo Di Sciara, Kent E. Carpenter

Biological Sciences Faculty Publications

1. This paper explores how criteria to identify important marine mammal areas (IMMAs) could be developed, and nested in existing global criteria. This process would consider 134 species of marine mammals. 2. Particular attention is given to two suites of global criteria to identify areas important for the persistence of marine biodiversity: Ecologically or Biologically Significant Areas (EBSAs) developed through the Convention on Biological Diversity (CBD), and Key Biodiversity Areas (KBAs) in revision through the International Union for the Conservation of Nature (IUCN). They are seen as mutually complementary in the development of IMMAs. 3. The specificities necessary for identifying …


The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead Jan 2014

The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead

OES Theses and Dissertations

Understanding the population structure and patterns of connectivity in marine fishes is essential when making predictions about a species' resiliency and persistence in an increasingly changing environment. The Atlantic Menhaden Brevoortia tyrannus is a clupeid that plays a critical role in the marine food web and supports one of the largest fisheries on the US East Coast. In addition to a decrease in overall numbers and spawning stock biomass, recruitment levels have remained low since the 1990s. Menhaden use numerous estuaries along the Atlantic coast for juvenile development before recruiting to the adult population and the contribution of each of …