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High-Frequency Temperature Variability Mirrors Fixed Differences In Thermal Limits Of The Massive Coral Porites Lobata, Daniel J. Barshis, Charles Birkeland, Robert J. Toonen, Ruth D. Gates, Jonathon H. Stillman Dec 2018

High-Frequency Temperature Variability Mirrors Fixed Differences In Thermal Limits Of The Massive Coral Porites Lobata, Daniel J. Barshis, Charles Birkeland, Robert J. Toonen, Ruth D. Gates, Jonathon H. Stillman

Biological Sciences Faculty Publications

Spatial heterogeneity in environmental characteristics can drive adaptive differentiation when contrasting environments exert divergent selection pressures. This environmental and genetic heterogeneity can substantially influence population and community resilience to disturbance events. Here, we investigated corals from the highly variable back-reef habitats of Ofu Island in American Samoa that thrive in thermal conditions known to elicit widespread bleaching and mortality elsewhere. To investigate the relative importance of acclimation versus site of origin in shaping previously observed differences in coral tolerance limits at Ofu Island, specimens of the common Indo-Pacific coral Porites lobata from locations with differing levels of thermal variability were …


Arthropod Transcriptional Activator Protein-1 (Ap-1) Aids Tick-Rickettsial Pathogen Survival In The Cold, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta Jul 2018

Arthropod Transcriptional Activator Protein-1 (Ap-1) Aids Tick-Rickettsial Pathogen Survival In The Cold, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Ixodes scapularis ticks transmit several pathogens to humans including rickettsial bacterium, Anaplasma phagocytophilum. Here, we report that A. phagocytophilum uses tick transcriptional activator protein-1 (AP-1) as a molecular switch in the regulation of arthropod antifreeze gene, iafgp. RNAi-mediated silencing of ap-1 expression significantly affected iafgp gene expression and A. phagocytophilum burden in ticks upon acquisition from the murine host. Gel shift assays provide evidence that both the bacterium and AP-1 influences iafgp promoter and expression. The luciferase assays revealed that a region of approximately 700 bp upstream of the antifreeze gene is sufficient for AP-1 binding to promote …


Adiposity And Fat Metabolism During Combined Fasting And Lactation In Elephant Seals, Melinda Fowler, Cory Champagne, Daniel Croker Jan 2018

Adiposity And Fat Metabolism During Combined Fasting And Lactation In Elephant Seals, Melinda Fowler, Cory Champagne, Daniel Croker

Biological Sciences Faculty Publications

Animals that fast depend on mobilizing lipid stores to power metabolism. Northern elephant seals (Mirounga angustirostris) incorporate extended fasting into several life-history stages: development, molting, breeding and lactation. The physiological processes enabling fasting and lactation are important in the context of the ecology and life history of elephant seals. The rare combination of fasting and lactation depends on the efficient mobilization of lipid from adipose stores and its direction into milk production. The mother elephant seal must ration her finite body stores to power maintenance metabolism, as well as to produce large quantities of lipid and protein rich …


Modelling The Effects Of Habitat And Hosts On Tick Invasions, Robyn M. Nadolny, Holly D. Gaff Jan 2018

Modelling The Effects Of Habitat And Hosts On Tick Invasions, Robyn M. Nadolny, Holly D. Gaff

Biological Sciences Faculty Publications

Many tick species are invading new areas because of anthropogenic changes in the landscape, shifting climatic variables and increasing populations of suitable host species and tick habitat. However, the relative influences of habitat and hosts in tick dispersal and tick population establishment remain in question. A spatially explicit agent-based model was developed to explore the spatio-temporal dynamics of a generic tick population in the years immediately following the introduction of ticks into a novel environment. The general model was then adapted to investigate a case study of two recent tick species invasions into the Mid-Atlantic United States. The recent simultaneous …


Better Living Through Chemistry: Addressing Emerging Antibiotic Resistance, Nathan P. Coussens, Ashley L. Molinaro, Kayla J. Culbertson, Tyler Peryea, Gergely Zahoránszky-Köhalmi, Matthew D. Hall, Dayle A. Daines Jan 2018

Better Living Through Chemistry: Addressing Emerging Antibiotic Resistance, Nathan P. Coussens, Ashley L. Molinaro, Kayla J. Culbertson, Tyler Peryea, Gergely Zahoránszky-Köhalmi, Matthew D. Hall, Dayle A. Daines

Biological Sciences Faculty Publications

The increasing emergence of multidrug-resistant bacteria is recognized as a major threat to human health worldwide. While the use of small molecule antibiotics has enabled many modern medical advances, it has also facilitated the development of resistant organisms. This minireview provides an overview of current small molecule drugs approved by the US Food and Drug Administration (FDA) for use in humans, the unintended consequences of antibiotic use, and the mechanisms that underlie the development of drug resistance. Promising new approaches and strategies to counter antibiotic-resistant bacteria with small molecules are highlighted. However, continued public investment in this area is critical …


Energy-Rich Mesopelagic Fishes Revealed As A Critical Prey Resource For A Deep-Diving Predator Using Quantitative Fatty Acid Signature Analysis, Chandra Goetsch, Melinda G. Conners, Suzanne M. Budge, Yoko Mitani, William A. Walker, Jeffrey F. Bromaghin, Samantha E. Simmons, Colleen Reichmuth, Daniel P. Costa Jan 2018

Energy-Rich Mesopelagic Fishes Revealed As A Critical Prey Resource For A Deep-Diving Predator Using Quantitative Fatty Acid Signature Analysis, Chandra Goetsch, Melinda G. Conners, Suzanne M. Budge, Yoko Mitani, William A. Walker, Jeffrey F. Bromaghin, Samantha E. Simmons, Colleen Reichmuth, Daniel P. Costa

Biological Sciences Faculty Publications

Understanding the diet of deep-diving predators can provide essential insight to the trophic structure of the mesopelagic ecosystem. Comprehensive population-level diet estimates are exceptionally difficult to obtain for elusive marine predators due to the logistical challenges involved in observing their feeding behavior and collecting samples for traditional stomach content or fecal analyses. We used quantitative fatty acid signature analysis (QFASA) to estimate the diet composition of a wide-ranging mesopelagic predator, the northern elephant seal (Mirounga angustirostris), across five years. To implement QFASA, we first compiled a library of prey fatty acid (FA) profiles from the mesopelagic eastern North Pacific. Given …


Natural History Of The Southern Bog Lemming In Southeastern Virginia, Robert K. Rose Jan 2018

Natural History Of The Southern Bog Lemming In Southeastern Virginia, Robert K. Rose

Biological Sciences Faculty Publications

The isolated subspecies of Southern Bog Lemming of southeastern Virginia, Synaptomys cooperi helaletes, has been studied extensively since its "rediscovery" in the Great Dismal Swamp in 1980. Multiple studies using pitfall traps, starting in the Great Dismal Swamp National Wildlife Refuge and then extending elsewhere in southeastern Virginia and adjacent northeastern North Carolina, have revealed lemmings to be much more widespread and often more common than previously believed, with their presence now confirmed as far west as Surry and Sussex counties, about 30 km east of Petersburg, Virginia. When present, lemmings often are among the most numerous members of …