INTEGRATIVE BIOLOGY THURSDAY SEMINAR SERIES
The IB Seminar Series will be held in the CAS Multidisciplinary Complex (CMC 147), 3:30PM on Thursdays. (CMC is along Leroy Collins Blvd, parking lot 2A/B, near BSF) MAP
ONLINE 2015 FALL WORKSHOP IN DATA ANALYSIS VIDEOS
In October 2015, the Department of Integrative Biology, working with the College of Arts and Science, ResearchOne, and the Interdisciplinary Data Sciences Consortium, offered a set of workshops on data analysis. Two of the lectures from the workshop are available (below) as online videos.
- Introduction to spatial linear models; Spatial linear models in R, by Simoneta Negrete Yankelevich, Instituto de Ecología A.C., Xalapa, Veracruz, Mexico. Spatial phenomena are important in many kinds of data, especially environmental data. This is an introduction to spatial linear models, a central set of tools for assessing spatial phenomena and beginning to quantify them. It is based on the chapter on this topic in Fox, Negrete, and Sosa (eds). 2015. Ecological statistics: contemporary theory and application. Oxford University Press. The workshop was given at the University of South Florida.
- Introduction to analysis of censored and truncated data, by Gordon Fox, USF Integrative Biology. Data in many settings are censored: we know only an inequality about some values - for example, that a particular value weighs less than the scale permits. In other settings, data are truncated: we aren't even recording the existence of certain types of values. There are some well-developed methods for analyzing these data; this is an introduction. It uses the chapter on this topic in Fox, Negrete, and Sosa, eds. (2015). Ecological statistics: contemporary theory and application. Oxford University Press.
Gordon Fox was featured in an interview on WMNF Public Radio (88.5 FM, Tampa, Florida) on the effects of climate change on the spread of diseases around the world. He pointed out that the recent outbreak of the Zika virus is not the only pathogen spreading in Florida, that the state is also falling victim to the Texas Phoenix Palm Decline , which is infecting trees including date palms and cabbage palms in Florida. Tampa is the center of the outbreak in the state. The disease is caused by a bacteria which was imported into the state with infected plants. Gordon discusses the problem with world travel and human interest in novel plants and animals introducing new species to new parts of the globe. These new species carry new diseases with them. Read his interview, or listen to it, at the WMNF RADIO site.
Tom and Beverly Porter continue to support USF Integrative Biology and Dr. Motta's lab since their daughter, Heather, graduated in 1997. Their donations to USF have helped Department of Integrative Biology students in the lab of Dr. Philip Motta, studying the feeding behavior of sharks, tagging sharks aboard a research vessel, taking field trips to the Florida Keys reefs to study fishes and in one-on-one mentoring, and in the lab of Dr. Stephen Deban, using high speed videography to compare feeding patterns of different salamander species. These are just a few of the valuable research opportunities USF's Integrative Biology students have taken part in. Learn more about the story, and the research opportunities in Integrative Biology in the following video:
The USF Faculty Senate Honors and Awards Council has concluded its deliberations for the 2016 Spring Semester, and selected Dr. Jason Rohr, (USF Integrative Biology), to receive the 2016 Jerome Krivanek Distinguished Teacher Award. The award will be presented later this year by the Provost’s office. Jason began his teaching career as an Assistant Professor in the USF Biology Department in 2007, and is currently an Associate Professor, teaching classes in the Department of Integrative Biology on parasitology, animal behavior, and graduate-level introductory and advanced biological statistics. He was recently appointed Director of the Center for Infectious Disease Ecology Research (CIDER), a newly formed research center at USF, to which the Department of Integrative Biology is affiliated. His world-renowned research includes studies on ecotoxicity of pesticides and herbicides, chytrid fungal effects on amphibians, and anthropogenic changes to ecosystems. Congratulations on your award!
USF and the Florida Board of Governors met recently to officially approve the establishment of a Center for Infectious Disease Ecology Research (CIDER) on campus. The Center will be affiliated with the USF Department of Integrative Biology. The purpose of the Center is to bring together researchers on campus that are interested in diseases ecology. It will also facilitate in the training of disease ecologists and attract new disease ecologist faculty to USF. Disease ecology is the interaction of the behavior and ecology of hosts with the biology of pathogens, as it relates to the impact of diseases on populations.
CHANTALE BÉGIN AND CHRISTOPHER OSOVITZ
The USF Transformation Implementation Leadership Team (TILT) has recommended for implementation and will provide support for proposals submitted to the team by two USF Integrative Biology faculty members, Chantale Bégin and Christopher Osovitz. Chantale joined Vasala Mohanakumar from Hillsborough Community College in submitting a proposal titled “Transforming STEM Education at USF and HCC”, while Chris joined an eight-member team that also included faculty from the USF Departments of CMMB, Chemistry, and Mathematics and faculty from HCC in submitting a proposal titled “Mathematics Foundation for Sciences”. Project STEER (Systemic Transformation of Education through Evidence-Based Reforms) is a program supported largely by a $3M NSF IUSE grant to a broadly representative USF team to develop an institutional culture that improves the retention rate and preparation of students who enter USF as STEM majors. STEER has a special focus on underrepresented groups. On January 30, STEER held an interdisciplinary retreat. One of the outcomes of the retreat was an invitation to faculty to submit course redesign proposals with support of STEER. Each proposed project was expected to enhance curricular alignment and adoption of evidence-based strategies, strategies that have been validated by extensive research to be effective in reaching the overall national goal. Chantale and Chris submitted proposals expected to reach these goals. TILT members will serve as advisors and consultants in the development of work plans to implement the proposals. The funding provided in the awards is in recognition of the additional effort the participating faculty will have to expend on these projects. Congratulations on your awards!
THOMAS CRISMAN AT STATE DEPARTMENT
Dr. Thomas Crisman, joint professor in USF Integrative Biology and the College of Public Health’s Department of Environmental and Occupational Health, recently concluded an a one year fellowship with the U.S. Department of State and USAID’s Jefferson Science Fellowship Program. He was one of 13 fellows chosen nationally to offer their insight on bridging science and U.S. policy. Working in the Office of Conservation and Water, Crisman led an expert group working to help with revisions of the environmental safeguards that the World Bank applies to all loans. He was also responsible for reviewing environmental assessment for large dams globally prior to World Bank funding approval. “I would give the State Department’s view before sending it to the Treasury for submittal to the World Bank,” Crisman said. He also helped set up a new program bringing together religious values of local people and water usage, taking into account local social values associated with water management. He started his efforts on the Balkans and will continue on to Albania, Macedonia and Croatia. Although his Jefferson Science fellowship has concluded, he is still continuing his work with the U.S. Department of the State as a Jefferson Science Fellow. In addition to this, Crisman has served for the past 20 years on the board of the United States–Israel Binational Science Foundation as one of five Americans responsible for overseeing the distribution of U.S.-Israeli funding for cooperative science between the two nations. He has also served as a consultant for numerous U.S. embassies around the world on water management issues. More of his story is featured in a story at USF College of Public Health News.
Christina Richards, (Assistant Professor, USF Integrative Biology), has been awarded a 2016-17 Fulbright U.S. Scholar grant for collaborative research and teaching at the Université de Rennes 1 in France, with collaborators Professor Malika Ainouche and Dr. Armel Salmon. The title of their proposal was “Enhancing the biology curriculum at University of South Florida and University of Rennes with ecological epigenetics: Merging ecology and epigenomics approaches to understand plant invasion”. The Fulbright program will provide Dr. Richards with the unique experience of teaching in an international setting. She has visited the University of Rennes and she collaborates with Dr. Koen Verhoeven at the Institute of Ecology in the Netherlands on several projects, but Dr. Richards has not had the chance to live in Europe for an extended period of time. Dr. Richards’ lab group has been investigating responses to different environmental challenges in native populations of Spartina alterniflora, which is a critical foundation plant species on the eastern and Gulf coasts of the United States. This plant is able to survive in an exceptionally broad range of environments in its native habitat, but it also has become a significant invasive plant around the globe. Professor Ainouche and Dr. Salmon work in the Mechanisms and Origin of Biodiversity (MOB) team of the research unit Ecosystèmes, Biodiversité, Evolution at University of Rennes in France. The MOB team has a unique program in plant biodiversity, with expertise in Biochemistry, Molecular Biology, Functional Genomics, and Evolutionary Biology, and they have particular emphasis on response to changing environments and anthropogenic pressures. As part of this team, Professor Ainouche and Dr. Salmon have worked on the molecular biology and genomics of Spartina alterniflora and related species. Dr. Richards and her fellow scholars will target publication of the results of their research in journals such as Ecology Letters or Molecular Ecology, and will present their results at the SSE and ESEB meetings in summer 2017 and at the 2018 joint international conference of the two societies in Montpelier, France. Through the Fulbright program, Dr. Richards will also have the opportunity to interact with new students who have developed academically in a different system and anticipates that she will have new ideas about her research and approaches in the United States when she return.
In a previous paper (Blood-brain barrier alterations provide evidence of subacute diaschisis in an ischemic stroke rat model, PLoS ONE), authors Svitlana Garbuzova-Davis, (Center of Excellence for Aging and Brain Repair, Morsani College of Medicine, Univ. of South Florida, Tampa, Fl.), Edward Haller, (USF Integrative Biology), Naoki Tajiri, (CEABR, USF), Avery Thomson, (CEABR, USF), Jennifer Barretta, (CEABR, USF), Stephanie Williams, (CEABR, USF), Eithan Haim, (CEABR, USF), Hua Qin, (CEABR, USF), Aric Frisina-Deyo, (CEABR, USF), Jerry Abraham, (CEABR, USF), Paul Sanberg, (CEABR, USF), Harry Van Loveren, (Dept. of Neurosurgery and Brain Repair, Morsani C. of M., USF), and Cesario V. Borlongan, (CEABR, USF) demonstrated blood-brain barrier impairment in remote contralateral brain areas in rats at 7 and 30 days after transient middle cerebral artery occlusion (tMCAO), indicating ischemic diaschisis. Their current study focused on effects of subacute and chronic focal cerebral ischemia on the blood-spinal cord barrier (BSCB). They observed BSCB damage on both sides of the cervical spinal cord in rats at 7 and 30 days post-tMCAO. Major BSCB ultrastructural changes in spinal cord gray and white matter included vacuolated endothelial cells containing autophagosomes, pericyte degeneration with enlarged mitochondria, astrocyte end-feet degeneration and perivascular edema; damaged motor neurons, swollen axons with unraveled myelin in ascending and descending tracts and astrogliosis were also observed. Evans Blue dye extravasation was maximal at 7 days. There was immunofluorescence evidence of reduction of microvascular expression of tight junction occludin, upregulation of Beclin-1 and LC3B immunoreactivities at 7 days and a reduction of the latter at 30 days post-ischemia. These novel pathological alterations on the cervical spinal cord microvasculature in rats after tMCAO suggest pervasive and long-lasting BSCB damage after focal cerebral ischemia, and that spinal cord ischemic diaschisis should be considered in the pathophysiology and therapeutic approaches in patients with ischemic cerebral infarction. Their current study is published in the Oxford Journal of Neuropathology and Experimental Neurology. The story of their research is featured in an article in ScienceDaily.
Muscle-powered movements are limited by the contractile properties of muscles and are sensitive to temperature changes. Elastic-recoil mechanisms can both increase performance and mitigate the effects of temperature on performance. Authors Jeffrey Scales, Charlotte Stinson and Stephen Deban, (USF Integrative Biology, Deban lab) compared feeding movements in two species of plethodontid salamanders, Bolitoglossa franklini and Desmognathus quadramaculatus, across a range of body temperatures (5-25°C) to better understand the mechanism of elastically powered, thermally robust movements. Bolitoglossa exhibited ballistic, elastically powered tongue projection with a maximum muscle mass specific power of 4,642 W kg -1 while Desmognathus demonstrated nonballistic, muscle-powered tongue projection with a maximum power of 359 W kg -1. Tongue-projection performance in Bolitoglossa was more thermally robust than that of Desmognathus, especially below 15°C. The improved performance and thermal robustness of Bolitoglossa was associated with morphological changes in the projector muscle, including elaborated collagen aponeuroses and the absence of myofibers attaching directly to the tongue skeleton. The elongated aponeuroses likely increase the capacity for elastic energy storage, and the lack of myofibers inserting on the tongue skeleton permits ballistic projection. These results suggest that relatively simple changes in myofiber architecture and the amount of connective tissue can improve the performance and functional robustness of movements in the face of environmental challenges such as variable temperature. Their study is published in the Journal of Experimental Zoology Part A Ecological Genetics and Physiology.
Brad Gemmell studies the methods of locomotion of various marine organisms, from plankton to siphonophores to jellyfish to lampreys. In a recent study on moon jellyfish, Aurelia aurita, Brad and his research associates discovered that the jellies, which must constantly keep swimming night and day, are more efficient than any other swimmers, using 48 percent less oxygen than any other animal to move. Their study found that the jellies produce highly efficient regions of high and low pressure around their domes as they contract and expand, sucking and pushing themselves forward in the water. Read the Scientific American Online article here for more interesting information on the jellies, and the original research published in Nature Communications in 2015 here.
The extent to which Marine Protected Areas (MPAs) benefit corals is contentious. On one hand, MPAs could enhance coral growth and survival through increases in herbivory within their borders; on the other, they are unlikely to prevent disturbances, such as terrestrial run-off, that originate outside their boundaries. Authors Chantale Bégin , (USF Integrative Biology), Christiane Schelten, (GEOMAR, Helmholtz Centre for Ocean Research, DE), Maggy Nugues, (Laboratoire d′Excellence ′CORAIL′, Perpignan Cedex, FR), Julie Hawkins, (Univ. of York, Heslington, UK), Callum Roberts, (Univ. of York, Heslington, UK), and Isabelle Côté, (Simon Fraser Univ., Burnaby, BC, CA) examined the effect of spatial protection and terrestrial sediment on the benthic composition of coral reefs in Saint Lucia. In 2011 (10 to 16 years after MPAs were created), the authors resurveyed 21 reefs that had been surveyed in 2001 and analyzed current benthic assemblages as well as changes in benthic cover over that decade in relation to protection status, terrestrial sediment influence (measured as the pro-portion of terrigenous material in reef-associated sediment) and depth. The cover of all benthic biotic components has changed significantly over the decade, including a decline in coral and increase in macroalgae. Protection status was not a significant predictor of either current benthic composition or changes in composition, but current cover and change in cover of several components were related to terrigenous content of sediment deposited recently. Sites with a higher proportion of terrigenous sediment had lower current coral cover, higher macroalgal cover and greater coral declines. Their results suggest that terrestrial sediment is an important factor in the recent degradation of coral reefs in Saint Lucia and that the current MPA network should be complemented by measures to reduce runoff from land. Their work is published in the journal PlosOne
Birds often face various stressors during feather renewing, for example, enduring infection with blood parasites. Because nutritional resources are typically limited, especially for wild animals, when an individual allocates energy to one physiological system, there is subsequently less for other processes, thereby requiring a trade-off. Potential trade-offs between malaria infection and feather growth rate have not been experimentally considered yet. Authors Courtney Coon, (Univ. of Pretoria, Onderstepoort, ZA), Luz Garcia-Longoria, (Univ. of Extremadura, Avda. De Elvas, ES), Lynn (Marty) Martin, (USF Integrative Biology), Sergio Magallanes, (Univ. of Extremadura, Avda. De Elvas, ES), Florentino de Lope, (Univ. of Extremadura, Avda. De Elvas, ES), and Alfonso Marzal, (Univ. of Extremadura, Avda. De Elvas, ES) conducted three studies to investigate whether a trade-off occurs among feather growth rate, malaria infection and host health conditions. First, they explored whether naturally infected and uninfected house sparrows differed in feather growth rate in the wild. Second, they asked whether experimental inoculation of malaria parasites and / or forcing the renewal of a tail feather. Finally, the authors evaluated whether individual condition was affected by experimentally-induced feather regrowth and / or malaria experimental infection. Their findings showed that feather growth rate was negatively affected by natural malaria infection status in free-living birds and by experimental infection in captive birds. Furthermore, birds that did not increase body mass or hematocrit during the experimental study had slower feather growth. Together these results suggest that infection with blood parasites has more negative health effects than the growth of tail feathers and that these two processes (response to blood parasite infection and renewal of feathers) are traded-off against each other. As such, their results highlight the role of malaria parasites as a potential mechanism driving other trade-offs in wild passerines. Their study is published in the Journal of Avian Biology.
Foraging modalities (e.g., passive, sit-and-wait, active) and traits are plastic in some species, but the extent to which this plasticity affects interspecific competition remains unclear. Using a long-term laboratory mesocosm experiment, authors David Jennings, (Univ. of Maryland, College Park, MD), James Krupa, (Univ. of Kentucky, Lexington, KY), and Jason Rohr, (USF Integrative Biology) quantified competition strength and the plasticity of foraging traits in a guild of generalist predators of arthropods with a range of foraging modalities. Each mesocosm contained eight passively foraging pink sundews, and they employed an experimental design where treatments were the presence or absence of a sit-and-wait foraging spider and actively foraging toad crossed with five levels of prey abundance. The authors hypothesized that actively foraging toads would outcompete the other species at low prey abundance, but that spiders and sundews would exhibit plasticity in foraging traits to compensate for strong competition when prey were limited. Results generally supported their hypotheses. Toads had a greater effect on sundews at low prey abundances, and toad presence caused spiders to locate webs higher above the ground. Additionally, the closer large spider webs were to the ground, the greater the trichome densities produced by sundews. Also, spider webs were larger in the presence of than without toads and as sundew numbers increased, and these effects were more prominent as resources became limited. Finally, spiders negatively affected toad growth only at low prey abundance. These findings highlight the long-term importance of foraging modality and plasticity of foraging traits in determining the strength of competition within and across taxonomic kingdoms. Future research should assess whether plasticity in foraging traits helps to maintain coexistence within this guild and whether foraging modality can be used as a trait to reliably predict the strength of competitive interactions. Their study is published in the Journal of Animal Ecology.
A study on the feeding performance of king mackerel, conducted by researchers in the Department of Integrative Biology and the University of Tampa, found its way into an article on sports fishing for king mackerel in Florida Sportsman magazine recently. The research work, “Feeding Performance of King Mackerel, Scomberomorus cavalla”, published in 2015 in the Journal of Experimental Zoology (Amber Ferguson, (USF Integrative Biology graduate, 2014), Daniel Huber, (Univ. of Tampa), Marc Lajeunesse, (USF Integrative Biology) and Philip Motta, (USF Integrative Biology), authors), was a comparative study of the feeding performance of king mackerel, including bite force and feeding mechanism. The mackerel bite force was compared to that of other bony fish and to sharks, with the conclusion that king mackerel rely on high speed impact of their teeth on prey fish to exert bite pressure, in contrast to sharks and fish with large jaw muscles which can generate high bite strength. The April 2016 Florida Sportsman article, titled “The Cutting Edge: What makes the kingfish such a deadly predator also makes it a fisherman’s favorite” features an interview with Philip Motta, one of the Experimental Zoology article co-authors. The Sportsman article quotes from the Zoology paper: “King mackerel, Scomberomorus cavalla, have relatively low performance for bite force compared with other fishes and relatively little of the forward predator force is experienced by the prey.” “However, king mackerel can attain high speeds to chase prey and use sharp teeth to impart high bite pressure, factors which apparently alleviate the need for high bite force.” Phil explains the mackerel feeding research in the article. Read the Experimental Zoology paper here and the Florida Sportsman article here.
Animal behaviour and the ecology and evolution of parasites are inextricably linked. For this reason, animal behaviorists and disease ecologists have been interested in the intersection of their respective fields for decades. Despite this interest, most research at the behaviour–disease interface focuses either on how host behaviour affects parasites or how parasites affect behaviour, with little overlap between the two. Yet, the majority of interactions between hosts and parasites are probably reciprocal, such that host behaviour feeds back on parasites and vice versa. Explicitly considering these feedbacks is essential for understanding the complex connections between animal behaviour and parasite ecology and evolution. Authors Vanessa Ezenwa, (Univ. of Georgia, Athens, GA), Elizabeth Archie, (Univ. of Notre Dame, Notre Dame, IN), Meggan Craft, (Univ. of Minnesota, St. Paul, MN), Lynn (Marty) Martin, (USF Integrative Biology), Janice Moore, (Colorado State Univ., Ft. Collins, CO) and Lauren White, (Univ. of Minnesota, St. Paul, MN) discuss how host behaviour–parasite feedbacks might operate and explore the consequences of feedback for studies of animal behaviour and parasites. For example, ignoring the feedback of host social structure on parasite dynamics can limit the accuracy of predictions about parasite spread. Likewise, considering feedback in studies of parasites and animal personalities may provide unique insight about the maintenance of variation in personality types. Finally, applying the feedback concept to links between host behaviour and beneficial, rather than pathogenic, microbes may shed new light on transitions between mutualism and parasitism. More generally, accounting for host behaviour–parasite feed-backs can help identify critical gaps in our understanding of how key host behaviors and parasite traits evolve and are maintained. Their review article is published in the Proceedings of the Royal Society B.
The factors driving the dominance of the Calvin–Benson–Bassham cycle (CBB) or reductive citric acid cycle (rCAC) in autotrophic microorganisms in different habitats are debated. Based on costs for synthesizing a few metabolic intermediates, it has been suggested that the CBB poses a disadvantage due to higher metabolic cost. Mary Mangiapia and Kathleen (KT) Scott, (USF Integrative Biology) conducted a study to extend the estimate of cost from metabolite synthesis to biomass synthesis. For 12 gammaproteobacteria (CBB) and five epsilonproteobacteria (rCAC), the amount of ATP to synthesize a gram of biomass from CO2 was calculated from genome sequences via metabolic maps. The eleven central carbon metabolites needed to synthesize biomass were all less expensive to synthesize via the rCAC (66%–89% of the ATP needed to synthesize them via CBB). Differences in cell compositions did result in differing demands for metabolites among the organisms, but the differences in cost to synthesize biomass were small among organisms that used a particular pathway (e.g. rCAC), compared to the difference between pathways (rCAC versus CBB). The rCAC autotrophs averaged 0.195 moles ATP per g biomass, while their CBB counterparts averaged 0.238. This is the first in silico estimate of the relative expense of both pathways to generate biomass. Their research is published in the Oxford journal FEMS Microbiology Letters. Their paper was selected as Editor’s Choice for the month of March, 2016!
The gammaproteobacterium Thiomicrospira crunogena XCL-2 is an aerobic sulfur-oxidizing hydrothermal vent chemolithoautotroph that has a CO2 concentrating mechanism (CCM), which generates intracellular dissolved inorganic carbon (DIC) concentrations much higher than extracellular, thereby providing substrate for carbon fixation at sufficient rate. This CCM presumably requires at least one active DIC transporter to generate the elevated intracellular concentrations of DIC measured in this organism. Authors Kristy Menning, (USF Dept. of Psychiatry), Balaraj Menon, (Univ. of Southern Mississippi, Hattiesburg, MS), Gordon Fox, (USF Integrative Biology), Kathleen (KT) Scott, (USF Integrative Biology) and the USF MCB4404L 2012 class conducted a study on the bacteria where the half-saturation constant (KCO2) for purified carboxysomal RubisCO was measured (276 ± 18 µM) which was much greater than the KCO2 of whole cells (1.03 µM), highlighting the degree to which the CCM facilitates CO2 fixation under low CO2 conditions. To clarify the bioenergetics powering active DIC uptake, cells were incubated in the presence of inhibitors targeting ATP synthesis (DCCD) or proton potential (CCCP). Incubations with each of these inhibitors resulted in diminished intracellular ATP, DIC, and fixed carbon, despite an absence of an inhibitory effect on proton potential in the DCCD-incubated cells. Electron transport complexes NADH dehydrogenase and the bc1 complex were found to be insensitive to DCCD, suggesting that ATP synthase was the primary target of DCCD. Given the correlation of DIC uptake to the intracellular ATP concentration, the ABC transporter genes were targeted by qRT-PCR, but were not upregulated under low-DIC conditions. As the T. crunogena genome does not include orthologs of any genes encoding known DIC uptake systems, these data suggest that a novel, yet to be identified, ATP- and proton potential-dependent DIC trans-porter is active in this bacterium. This transporter serves to facilitate growth by T. crunogena and other Thiomicrospiras in the many habitats where they are found. Their study is published in the Archives of Microbiology.
Understanding the processes driving the distribution of mid-water prey such as euphausiids and lanternfish is important for effective management and conservation. In the vicinity of abrupt topographic features such as banks, seamounts and shelf-breaks, mid-water faunal biomass is often elevated, making these sites candidates for special protection. Authors Tom Letessier, (Univ. of Western Australia, Crawley, WA, AU), Martin Cox, (Australian Antarctic Division, Kingston, AU), Jessica Meeuwig, (Univ. of Western Australia, Crawley, WA, AU), Philipp Boersch-Supan, (USF Integrative Biology), and Andrew Brierley, (Univ. of St. Andrew, Fife, UK) investigated the spatial distribution of water column acoustic backscatter - a proxy for macrozoo-plankton and fish biomass - in the 9 km transition zone between the pelagos and coral atolls in the Chagos Archipelago (6° N, 72° E). The purpose was to determine the magnitude and distance over which bathymetry may enhance biomass in the mid-water, and thereby identify the scale over which static topographic features could influence the open ocean. Two distinct sound scattering layers were identified, from the surface to 180 m and from 300 to 600 m, during daytime. Both layers exhibited significant increases in backscatter near features. Close to features, the shallow layer backscatter was ca. 100 times higher and was driven partly by increasing numbers of larger individuals, evident as single target echoes. The authors determined the regional scale of influence of features on pelagic biomass enhancement to be ca. 1.8 km in the Chagos Archipelago, and suggest possible ecological explanations that may support it. The authors report that their approach determining the scale of influence of bathymetry should be applied during the process of marine reserve design, in order to improve protection of mid-water fauna associated with topographical features, such as seamounts and coral reefs. Their study is published in the journal Marine Ecology Progress Series.
Effective population size is a fundamental parameter in population genetics, and factors that alter effective population size will shape the genetic characteristics of populations. Habitat disturbance may have a large effect on genetic characteristics of populations by influencing immigration and gene flow, particularly in fragmented habitats. Authors Aaron Schrey, (Armstrong State Univ., Savannah, GA), Alexandria Ragsdale, (Armstrong State Univ., Savannah, GA), Earl McCoy, (USF Integrative Biology) and Henry Mushinsky, (USF Integrative Biology) used the Florida Sand Skink (Plestiodon reynoldsi) to investigate the effect of fire-based habitat disturbances on the effective population size in the highly threatened, severely fragmented, and fire dependent Florida scrub habitat. They screened seven microsatellite loci in 604 individuals collected from 12 locations at Archbold Biological Station. Archbold Biological Station has an active fire management plan and detailed records of fires dating to 1967. Their objective was to determine how the timing, number, and intervals between fires affect effective population size, focusing on multiple fires in the same location. Effective population size was higher in areas that had not been burned for more than ten years and decreased with number of fires and shorter time between fires. A similar pattern was observed in abundance: increasing abundance with time-since-fire and decreasing abundance with number of fires. The ratio of effective population size to census size was higher at sites with more recent fires and tended to decrease with time-since-last-fire. The results of their study suggest that habitat disturbances, such as fire, may have a large effect in the genetic characteristics of local populations and that Florida Sand Skinks are well adapted to the natural fire dynamics required to maintain Florida scrub. Their paper is published in the Journal of Heredity .
Multi-drug resistant fecal bacteria (MRF) including gram-negative Escherichia coli and positive Enterococcus faecium are of prime concern to food safety and public health. This study was performed to test efficacy of a natural antimicrobial, polymeric chitosan-based nanoparticles combined with ZnO to in situ intervention. Authors Alya Limayem, (USF Dept. of Cell Biology, Microbiology and Molecular Biology), Andrew Micciche, (USF Dept. of Cell Biology, Microbiology and Molecular Biology), Edward Haller, (USF Integrative Biology), Chao Zhang, (USF Dept. of Cell Biology, Microbiology and Molecular Biology), and Shyam Mohapatra, (USF College of Medicine, Dept. of Internal Medicine) examined the effects of nanoparticles (NPs) of chitosan, ZnO alone and a combination of chitosan and ZnO, (CZNPs) at 1:1 on co-cultured nosocomial MRFs and a wild type (WT) through the minimal inhibitory concentration (MIC) test which conforms to National Standards, NCCLS. Toward elucidating visually the mechanistic effects of NPs alone and CZNPs on MRF and WT strains, Transmission Electronic Microscopy (TEM) was performed. While chitosan 1 (C1) and 2 (C2) alone with a molecular weight of 3 kDa and 50 kDa, respectively inhibited resistant E. coli strain (E. coli BAA-2471), they were ineffective at a concentration less than 5 mg/mL on either E. faecium strains and the co-cultures. ZnO and chitosan alone did not exhibit optimal effects on MRF strains and cultures alone. However, the MRF co-culture, E. coli BAA-2471 and E. faecium 1449 was completely inhibited by the C1ZNPs with an average minimal MIC of 0.781 mg/mL, and a maximal MIC of 1.302 mg/mL. Synergism of C1ZNPs over C2ZNPs proved to be predominantly inhibitive of MRF over WT co-cultures. Further TEM analyses demonstrated attachment and lysis of MRFs at 16h past treatment. Conclusively, CZNPs inhibit MRF co-cultures and is a promising in vivo intervention agent. Their study is published in the Kenkyu Journal of Nanotechnology and Nanoscience.
The impact of widespread and common environmental factors, such as chemical contaminants, on infectious disease risk in amphibians is particularly important because both chemical contaminants and infectious disease have been implicated in worldwide amphibian declines. Authors Uthpala Jayawardena, (Univ. of Peradeniya, Peradeniya, LK), Jason Rohr, (USF Integrative Biology), Ayanthi Navaratne, (Univ. of Peradeniya, Peradeniya, LK), Priyanie Amerasinghe, (International Water Management Institute, Hyderabad, Andhra Pradesh, IN), and Rupika Rajakaruna, (Univ. of Peradeniya, Peradeniya, LK) report on the lone and combined effects of exposure to parasitic cercariae (larval stage) of the digenetic trematode, Acanthostomum burminis, and four commonly used pesticides (insecticides: chlorpyrifos, dimethoate; herbicides: glyphosate, propanil) at ecologically relevant concentrations on the survival, growth, and development of the common hourglass tree frog, Polypedates cruciger Blyth 1852. There was no evidence of any pesticide-induced mortality on cercariae because all the cercariae successfully penetrated each tadpole host regardless of pesticide treatment. In isolation, both cercarial and pesticide exposure significantly decreased frog survival, development, and growth, and increased developmental malformations, such as scoliosis, kyphosis, and also edema and skin ulcers. The authors found that the combination of cercariae and pesticides generally posed greater risk to frogs than either factor alone by decreasing survival or growth or increasing time to metamorphosis or malformations. The exception was that lone exposure to chlorpyrifos had higher mortality without than with cercariae. They report that, consistent with mathematical models that suggest that stress should increase the impact of generalist parasites, the weight of the evidence from the field and laboratory suggests that ecologically relevant concentrations of agrochemicals generally increase the threat that trematodes pose to amphibians, highlighting the importance of elucidating interactions between anthropogenic activities and infectious disease in taxa of conservation concern. Their study is published in the journal EcoHealth.
The potential benefits of physiology for conservation are well established and include greater specificity of management techniques, determination of cause–effect relationships, increased sensitivity of health and disturbance monitoring and greater capacity for predicting future change. While descriptions of the specific avenues in which conservation and physiology can be integrated are readily available and important to the continuing expansion of the discipline of ‘conservation physiology’, to date there has been no assessment of how the field has specifically contributed to conservation success. The goal of conservation physiology is to foster conservation solutions and it is therefore important to assess whether physiological approaches contribute to downstream conservation outcomes and management decisions. Authors Christine Madliger, (Univ. of Windsor, Windsor, ON, CA), Steven Cooke, (Charleston Univ., Ottawa, ON, CA), Erica Crespi, (Washington State Univ., Pullman, WA), Jennifer Funk, (Chapman Univ., Orange, CA), Kevin Hultine, (Desert Botanical Garden, Phoenix, AZ), Kathleen Hunt, (New England Aquarium, Boston, MA), Jason Rohr, (USF Integrative Biology), Brent Sinclair, (Western Univ., London, ON, CA), Cory Suski, (Univ. of Illinois, Urbana, IL), Craig Willis, (Univ. of Winnipeg, Winnipeg, MB, CA), and Oliver Love, (Univ. of Windsor, Windsor, ON, CA) present eight areas of conservation concern, ranging from chemical contamination to invasive species to ecotourism, where physiological approaches have led to beneficial changes in human behaviour, management or policy. The authors discuss the shared characteristics of these successes, identifying emerging themes in the discipline. Specifically, they conclude that conservation physiology: (i) goes beyond documenting change to provide solutions; (ii) offers a diversity of physiological metrics beyond glucocorticoids (stress hormones); (iii) includes approaches that are transferable among species, locations and times; (iv) simultaneously allows for human use and benefits to wildlife; and (v) is characterized by successes that can be difficult to find in the primary literature. Overall, the authors submit that the field of conservation physiology has a strong foundation of achievements characterized by a diversity of conservation issues, taxa, physiological traits, ecosystem types and spatial scales. In concluding their paper, the authors express hope that these concrete successes will encourage the continued evolution and use of physiological tools within conservation-based research and management plans. Their study is published in the journal Conservation Physiology.
While traits and trait plasticity are partly genetically based, investigating epigenetic mechanisms may provide more nuanced understanding of the mechanisms underlying response to environment. Using ampliﬁed fragment length polymorphism (AFLP) and methylation-sensitive AFLP, authors Christy Foust, (USF Integrative Biology), Veronica Priete, (Netherlands Institute of Ecology, Wageningen, NL), Aaron Schrey, (Armstrong State Univ., Savanah, GA), Mariano Alvarez, (USF Integrative Biology), Marta Robertson, (USF Integrative Biology), Koen Verhoven, (Netherlands Institute of Ecology, Wageningen, NL), and Christina Richards, (USF Integrative Biology) tested the hypothesis that differentiation to habitats along natural salt marsh environmental gradients occurs at epigenetic, but not genetic loci in two salt marsh perennials. They detected signiﬁcant genetic and epigenetic structure among populations and among subpopulations, but found multilocus patterns of differentiation to habitat type only in epigenetic variation for both species. In addition, more epigenetic than genetic loci were correlated with habitat in both species. When the authors analyzed genetic and epigenetic variation simultaneously with partial Mantel, they found no correlation between genetic variation and habitat and a signiﬁcant correlation between epigenetic variation and habitat in Spartina alterniﬂora. In Borrichia frutescens, they found signiﬁcant correlations between epigenetic and/or genetic variation and habitat in four of ﬁve populations when populations were analyzed individually, but there was no signiﬁcant correlation between genetic or epigenetic variation and habitat when analyzed jointly across the ﬁve populations. Their analyses suggest that epigenetic mechanisms are involved in the response to salt marsh habitats, but also that the relationships among genetic and epigenetic variation and habitat vary by species. They report that site-speciﬁc conditions may also cloud the ability to detect response in replicate populations with similar environmental gradients. The authors pose that future studies analyzing sequence data and the correlation between genetic variation and DNA methylation will be powerful to identify the contributions of genetic and epigenetic response to environmental gradients. Their study is published in the journal Molecular Ecology.
Low temperature reduces the performance of muscle-powered movements, but in movements powered by elastic recoil mechanisms, this effect can be mitigated and performance can be increased. To better understand the morphological basis of high performance and thermal robustness of elastically powered movements, Stephen Deban and Jeffrey Scales compared feeding dynamics at a range of temperatures (5–25°C) in two species of terrestrial plethodontid salamanders, Plethodon metcalfi and Ensatina eschscholtzii, which differ in tongue muscle architecture and the mechanism of tongue projection. They found that Ensatina is capable of ballistic projection with a mean muscle mass-specific power of 2100 W kg−1, revealing an elastic mechanism. Plethodon, in contrast, projected its tongue non-ballistically with a mean power of only 18 W kg−1, indicating it is muscle powered. Ensatina projected its tongue significantly farther than Plethodon and with dynamics that had significantly lower thermal sensitivity at temperatures below 15°C. These performance differences were correlated with morphological differences, namely elongated collagenous aponeuroses in the projector muscle of Ensatina as compared with Plethodon, which are likely the site of energy storage, and the absence in Ensatina of projector muscle fibers attaching to the tongue skeleton that allows projection to be truly ballistic. These findings demonstrate that, in these otherwise similar species, the presence in one species of elaborated connective tissue in series with myofibers confers not only 10-fold greater absolute performance but also greater thermal robustness of performance. They conclude that changes in muscle and connective tissue architecture are sufficient to alter significantly the mechanics, performance and thermal robustness of musculoskeletal systems. Their paper is published in the Journal of Experimental Biology.
miRNAs can regulate cellular survival in various cancer cell types. Recent evidence implicates the formation of lipid droplets as a hallmark event during apoptotic cell death response. It is presently unknown whether MIR494, located at 14q32 which is deleted in renal cancers, reduces cell survival in renal cancer cells and if this process is accompanied by changes in the number of lipid droplets in the cells. Authors Punashi Dutta, (USF Cell Biology, Microbiology and Molecular Biology), Edward Haller, (USF Integrative Biology), Arielle Sharp, (USF Cell Biology, Microbiology and Molecular Biology), and Meera Nanjundan, (USF Cell Biology, Microbiology and Molecular Biology) conducted a study using 769-P renal carcinoma cells to investigate the role of MIR494 in renal cell cancer survival. Control or MIR494 mimic was expressed in these cells following which cell viability (via crystal violet) and apoptotic cell numbers (via Annexin V/PI staining) were assessed. By western blotting, MIR494 cellular responses were validated using MIR494 antagomir and Argonaute 2 siRNA. Transmission electron microscopy (TEM) was performed in MIR494-transfected 769-P cells to identify ultrastructural changes. LipidTOX green neutral lipid staining and cholesterol measurements were conducted to assess accumulation of lipids droplets and total cholesterol levels, respectively, in MIR494 expressing 769-P cells. Indirect immunofluorescence and western analyses were also performed to examine changes in mitochondria organization. Co-transfection of MIR494 mimic with siRNA targeting LC3B and ATG7 was conducted to assess their contribution to formation of lipid droplets in MIR494-expressing cells. MIR494 expression reduces viability of 769-P renal cancer cells; this was accompanied by increased cleaved PARP (an apoptotic marker) and LC3B protein. Further, expression of MIR494 increased LC3B mRNA levels and LC3B promoter activity (2.01-fold; 50% increase). Interestingly, expression of MIR494 markedly increased multilamellar bodies and lipid droplets (by TEM and validated by LipidTOX immunostaining) while reducing total cholesterol levels. Via immunocytochemistry, we observed increased LC3B-associated endogenous punctae upon MIR494 expression. In contrast to ATG7 siRNA, knockdown of LC3B reduced the numbers of lipid droplets in MIR494-expressing cells. The results of this study also identified that MIR494 expression altered the organization of mitochondria which was accompanied by co-localization with LC3B punctae, decreased PINK1 protein, and altered Drp1 intracellular distribution. Collectively, the study findings indicate that MIR494 reduces cell survival in 769-P renal cancer cells which is accompanied by increased lipid droplet formation (which occurs in a LC3B-dependent manner) and mitochondrial changes. The study is published in the journal BioMed Central Cancer.
Lynn (Marty) Martin and Stephanie Gervasi, (USF Integrative Biology) are featured in a Bioscience Advance Access article titled “Immunology Gone Wild”. The article discusses the relatively new field of ecoimmunology, sometimes called wild immunology, which got its start with a landmark Science paper by William Hamilton and Marlene Zuk in 1982 that discussed the links between parasites and sexual selection in passerines. Their paper concluded that elaborate traits such as colorful plumage in the birds may communicate disease resistance to females of the species. In following decades, ecologists continued studying immune systems of wild animals, without precise tools. Today, immunologists are joining their ranks, adding tools to their studies, bringing new insight to the research and fostering the field of ecoimmunology. The article discusses highlights of some previous ecoimmunologic research as well as current work in rodent and avian models. Marty’s lab is involved in studies on passerine species such as zebra finch and house sparrows.
In endometriosis, the increased survival potential of shed endometrial cells (which normally undergo anoikis) is suggested to promote lesion development. One mechanism that may alter anoikis is autophagy. Using an autophagic flux inhibitor hydroxychloroquine (HCQ), authors Abigail Ruiz, (USF Cell Biology, Microbiology and Molecular Biology), Stephanie Rockfield, (USF Cell Biology, Microbiology and Molecular Biology), Nicholas Taran, (USF Cell Biology, Microbiology and Molecular Biology), Edward Haller, (USF Integrative Biology), Robert Engelman, (USF Pathology and Cell Biology), Idhaliz Flores , (Ponce Research Institute, Ponce, PR), Paola Panina-Bordignon, (IRCCS Ospedale San Raffaele, Milan, IT), and Meera Nanjundan, (USF Cell Biology, Microbiology and Molecular Biology), identified that it reduces the in vitro survival capacity of human endometriotic and endometrial T-HESC cells. They also identified that HCQ could decrease lesion numbers and disrupt lesion histopathology, as well as increase the levels of peritoneal macrophages and the IP-10 (10 kDa interferon-γ-induced protein) chemokine in a mouse model of endometriosis. The authors noted that RNA levels of a subset of autophagic markers were reduced in lesions relative to uterine horns from endometriosis-induced (untreated) mice. In addition, the RNA levels of autophagic markers were decreased in uterine horns of endometriosis-induced mice compared with those from controls. However, they noted that protein expression of LC3B (microtubule-associated protein 1 light-chain 3ß; an autophagic marker) was increased in uterine horns of endometriosis-induced mice compared with uterine horns of controls. By immunohistochemical staining of a human endometriosis-focused tissue microarray, they observed LC3B expression predominantly in epithelial relative to stromal cells in both eutopic and ectopic endometria. Via transmission electron microscopy, cells from eutopic endometria of endometriosis-induced mice contained more lipid droplets (rather than autophagosomes) compared with uterine horns from controls. Collectively, their findings indicated that the autophagic pathway is dysregulated in both ectopic and eutopic endometrium in a murine model of endometriosis and that HCQ has potential as a therapeutic agent for women afflicted with endometriosis. Their study is published in the Nature journal Cell Death and Disease.
Pathogen identification and microbial source tracking (MST) to identify sources of fecal pollution improve evaluation of water quality. They contribute to improved assessment of human health risks and remediation of pollution sources. Authors Xiang Li, (West Virginia Univ., Morgantown, WV), Valerie (Jody) Harwood, (USF Integrative Biology), Bina Nayak, (USF Integrative Biology) and Jennifer Weidhaas, (West Virginia Univ., Morgantown, WV) used an MST microarray to simultaneously detect genes for multiple pathogens and indicators of fecal pollution in freshwater, marine water, sewage-contaminated fresh and marine water and treated wastewater. Dead-end ultrafiltration (DEUF) was used to concentrate 28 organisms from water samples, yielding a recovery efficiency of > 95% for Escherichia coli and human polyomavirus. Whole genome amplification (WGA) increased gene copies from ultrafiltered samples and increased the sensitivity of the microarray. Viruses, (adenovirus, bocavirus, Hepatitis A virus, and human polyomaviruses) were detected in sewage-contaminated samples. Pathogens such as Legionella pneumophila, Shigella flexneri, and Campylobacter fetus were detected along with genes conferring resistance to aminoglycosides, beta-lactams, and tetracycline. Non-metric dimensional analysis of MST marker genes grouped sewage-spiked freshwater and marine samples with sewage, and apart from other fecal sources. Sensitivity (percentage true positives) of the microarray probes for gene targets anticipated in sewage was 51–57% and was lower than specificity (79–81%, percentage true negatives). A linear relationship between gene copies determined by quantitative PCR and microarray fluorescence was found, indicating the semi-quantitative nature of the MST microarray. Their results indicate that ultrafiltration coupled with WGA provides sufficient nucleic acids for detection of viruses, bacteria, protozoa, and antibiotic resistance genes by the microarray in applications ranging from beach monitoring to risk assessment. Their study is published in the journal Applied and Environmental Microbiology.
Pesticides have a pervasive presence in aquatic ecosystems throughout the world. While pesticides are intended to control fungi, insects, and other pests, their mechanisms of action are often not specific enough to prevent unintended effects, such as on non-target microbial populations. Microorganisms, including algae and cyanobacteria, protozoa, aquatic fungi, and bacteria, form the basis of many food webs and are responsible for crucial aspects of biogeochemical cycling; therefore, the potential for pesticides to alter microbial community structures must be understood to preserve ecosystem services. Authors Zachery Staley, (postdoc, Univ. of Western Ontario, London, Ontario, CA), Valerie (Jody) Harwood, (USF Integrative Biology) and Jason Rohr, (USF Integrative Biology) wrote a review article that examines studies focusing on direct population-level effects and indirect community-level effects of pesticides on microorganisms. Generally, insecticides, herbicides, and fungicides were found to have adverse direct effects on algal and fungal species. Insecticides and fungicides also had deleterious direct effects in the majority of studies examining protozoa species, although herbicides were found to have inconsistent direct effects on protozoans. Their synthesis revealed mixed or no direct effects on bacterial species among all pesticide categories, with results highly dependent on the target species, chemical, and concentration used in the study. Examination of community-level, indirect effects revealed that all pesticide categories had a tendency to reduce higher trophic levels, thereby diminishing top-down pressures and favoring lower trophic levels. Often, indirect effects exerted greater influence than direct effects. However, few studies have been conducted to specifically address community-level effects of pesticides on microorganisms, and further research is necessary to better understand and predict the net effects of pesticides on ecosystem health. Their review is published in Critical Reviews in Toxicology.
Water loss compromises functions performed by wetland ecosystems. Efforts to rehabilitate wetland function typically begin with attempts to reestablish hydrology. These activities are often not monitored, so tools to extract information from them could partly offset the lost opportunity to learn from whole-ecosystem hydrological manipulation. In 2002, groundwater abstraction was lessened by 35% throughout 1700 km2 of west-central Florida (USA). Author David Lewis, (USF Integrative Biology) assembled a pathway of correlations to project how this hydrological manipulation affected water levels and soil carbon (C) storage in overlying wetlands. Parameter values and residual error in these statistical models were resampled from known variances, thereby propagating uncertainty through the pathway of relationships, and expressing the response of soil C probabilistically. Projected soil C probability distributions were most distinguishable between full and moderate (30% less) abstraction. With more severe abstraction cutbacks, gains in projected soil C became more marginal and uncertain, suggesting that wetland soil C pools are not notably impacted by low-volume groundwater abstraction. Reducing uncertainty in projected soil C will require better under-standing the dynamic response of soil C to increases in the amount of time that wetland soil is inundated. The step-by-step error propagation routine presented here is a platform for assimilating information from diverse sources in order to project probabilistic responses of ecosystem function to wetland restoration attempts, and it helps identify where further certainty is most wanted in a pathway of cause–effect relationships. His study is published in the journal Ecological Indicators.
Recently, Chantale Bégin, Instructor in USF Integrative Biology, taught a course titled Tropical Marine Ecosystems (BSC 4933). It was 3-credit course that was held half on the USF campus and half in the British Virgin Islands. While at USF, 20 students learned about mangroves, seagrasses and coral reef ecosystems, learning to identify common Caribbean invertebrates (including corals), fish and macrophytes, and acquired scientific diver in training status with AAUS (the American Academy for Underwater Science). After this initial training at USF, students traveled to Tortola, where they boarded the 112ft sailing vessel Argo. Over the 10 days that the class was aboard Argo, they sailed to several sites on the islands Tortola, Peter Island, Virgin Gorda, Guana, Sandy Spit and Jost Van Dyke. They gained experience using scuba diving and snorkeling to carry out standard benthic surveys and gather data on coral reefs, seagrass beds and mangroves. Students each completed 12 dives while in the BVI, and thereby gained full AAUS scientific diver status. After the BVI, the class met again in Tampa for a couple of days to analyze the data they collected. Among other things, they compared coral reef communities at various depth, quantified invertebrate density and richness in seagrass beds and mangrove roots, and examined the use of mangroves by several species of reef fishes.
Terry-René Brown, (Ph.D. Candidate, Scott lab, USF Integrative Biology), has been awarded a 2016-17 Fulbright-Schuman European Union Affairs Program grant for collaborative research on two environmental policy projects in the European Union (EU). The title of her proposal was “Climate Change and Biodiversity: Science and Policy in the European Union.” The Fulbright grant will provide René the opportunity to work with Dr. Valerie Kapos, Head of the Programme for Climate Change and Biodiversity at the United Nations Environment Programme-World Conservation Monitoring Centre (UNEP-WCMC), on a project investigating the impacts of climate change mitigation on biodiversity. The project will involve identifying the climate change mitigation measures the EU financially supports and assessing the positive and negative impacts these measures may have on biodiversity. Results from these studies will help direct UNEP-WCMC program priorities and will also be used to inform the EU and member states of the effects of climate change mitigation policies on biodiversity with the objective of promoting measures that enhance biodiversity and recommending safeguards for those that diminish biodiversity. René’s second host will be the Netherlands Institute of Ecology (NIOO-KNAW) with Dr. Lisette de Senerpont Domis, Head of the Aquatic Knowledge Centre Wageningen. This project will involve a large-scale meta-analysis of climate, biodiversity and water quality data collected in the Netherlands as a requirement of EU law under the Water Framework and Bathing Water Directives. The proposed project would involve analyzing these data along with historical and meteorological data to determine the relationships between climate, biodiversity, and water quality, and to determine the extent to which monitoring targets have been met. During her stay in the Netherlands, René and her host will convene a water management workshop, inviting water managers from other EU member states (e.g., Belgium, Czech Republic, Greece, Italy, Poland, and Spain); the goals of the workshop are to present and discuss their results and to invite related presentations from other water managers, to help shape water quality monitoring practices in the EU. René hopes that the results of both studies will advance the state of climate change policy and biodiversity protection in the EU, and will be applicable to the US and beyond. Congratulations on receiving such a prestigious grant!
Sarah Burgan, Master’s degree candidate in the Martin lab (USF Integrative Biology), was recently awarded an Animal Behavior Society student research grant for her studies on house sparrows. Sarah’s proposal was titled "Repeated Parasite Exposure: Implications for Host Defense Strategy and Transmission." The aim of her research is to investigate the defense strategies (i.e., resistance and tolerance) of house sparrows upon exposure to West Nile virus. By connecting physiological processes within hosts to their competence to transmit parasites, she believes that researchers may better understand the influence of individual hosts on population- and community-level disease dynamics. A reviewer of Sarah’s application wrote: “The ABS student grant proposal entitled “Repeated parasite exposure: implications for host defense strategy and transmission” has significant broad implications in two areas: 1) it concerns the impact of the interaction of disease tolerance and resistance at different levels of biological structure --the individual host and the population as a virus reservoir; and 2) it concerns a significant disease threat to less tolerant bird species as well as a humans. These two points were succinctly reviewed as well as the background of the relevant organisms and virus making this integrative biology study proposal interesting to read. The experimental procedure is clearly indicated including how the threshold and resistance will be measured by specific parameters concerning physiology. The predictions and rationale for the predictions are clearly stated for the measured parameters. It was good to see the thought that was put into the statistical analysis beforehand.” Congratulations, Sarah!
KELLI CARTER, CHRISTOPHER HAGGERTY, JASON RICHARDSON AND LAUREN VANMAURIK
Thomas and Beverly Porter had a daughter who graduated from USF in 2002 with a Master’s Degree in Biology. She did her thesis work in the lab of Dr. Philip Motta. Since her graduation, the Porter family has been a generous and supportive donor to USF, establishing the Porter Family Foundation. They have generously supported research in the Motta lab and helped many undergraduate and graduate students by providing grant money for student research in Integrative Biology, have facilitated numerous scientific publications, and each year helped fund teaching trips aboard Florida Institute of Oceanography ships. Their donations have allowed students to participate in shark tagging and fish collecting trips aboard the R/V Bellows. This year, four Integrative Biology research labs were given Porter Family Foundation research awards to support the research conducted by Kelli Carter, Christopher Haggerty, Jason Richardson and Lauren VanMaurik. The funds support research in their major professor’s labs in the I B Department. Congratulations on the accomplishment!
Humans are altering the distribution of species by changing the climate and disrupting biotic interactions and dispersal. A fundamental hypothesis in spatial ecology suggests that these effects are scale dependent; biotic interactions should shape distributions at local scales, whereas climate should dominate at regional scales. If so, common single-scale analyses might misestimate the impacts of anthropogenic modifications on biodiversity and the environment. However, large-scale datasets necessary to test these hypotheses have not been available until recently. Authors Jeremy Cohen, (USF Integrative Biology), David Civitello, (USF Integrative Biology), Amber Brace, (USF Integrative Biology), Erin Feichtinger, (USF Integrative Biology), C. Nicole Ortega, (USF Integrative Biology), Jason Richardson, (USF Integrative Biology), Erin Sauer, (USF Integrative Biology), Xuan Liub, (Chinese Acad. of Sciences, Beijing, CN) and Jason Rohr (USF Integrative Biology) conducted a cross-continental, cross-scale (almost five orders of magnitude) analysis of the influence of biotic and abiotic processes and human population density on the distribution of three emerging pathogens: the amphibian chytrid fungus implicated in worldwide amphibian declines and West Nile virus and the bacterium that causes Lyme disease (Borrelia burgdorferi), which are responsible for ongoing human health crises. In all three systems, the authors show that biotic factors were significant predictors of pathogen distributions in multiple regression models only at local scales (~102-103km2), whereas climate and human population density always were significant only at relatively larger, regional scales (usually >104km2). Spatial autocorrelation analyses revealed that biotic factors were more variable at smaller scales, whereas climatic factors were more variable at larger scales, as is consistent with the prediction that factors should be important at the scales at which they vary the most. Finally, no single scale could detect the importance of all three categories of processes. These results highlight that common single-scale analyses can misrepresent the true impact of anthropogenic modifications on biodiversity and the environment. Their study is published in the journal PNAS.
Suzanne Young is co-author on a review paper published as part of a special issue of Journal of Environmental Quality, product of a USDA funded workshop to address antibiotic resistance in agroecosystems. The paper is related to her dissertation work on antibiotic resistance in the environment, coadvised by Dr. Jody Harwood and Dr. Jason Rohr (USF Integrative Biology). Various culture-based methodologies are used in assessment of antibiotic resistance in samples collected in agroecosystems. Culture-based methods commonly involve isolating target bacteria on general or selective media and assessing growth in response to specific concentrations of antibiotics. The advantages of culture-based methods are multifold. In particular, isolation of bacteria is key to understanding phenotypic characteristics of isolates and their resistance patterns, and most national and international antibiotic resistance monitoring projects are isolate based. Authors Jean McLain, (Univ. of Arizona, Tucson, AZ), Eddie Cytryn, ( Agricultural Research Organization, Bet Dugan, IL), Lisa Durso, (Univ. of Nebraska, Lincoln, NE), and Suzanne Young, (USF Integrative Biology) wrote the review covering current knowledge of bacterial groups and antibiotics commonly targeted in resistance studies using bacterial culture and discusses the range in methods used, data interpretation, and factors supporting and confounding the use of culture-based methods in assessment of antibiotic resistance. Gaps in knowledge related to study design and resistance databases are discussed. Finally, a case is made for the integration of culture-based and molecular methods to better inform our understanding of antibiotic resistance in agroecosystems. Their review is published in the Journal of Environmental Quality.
Empirical patterns that emerge from an examination of food webs over gradients of environ-mental variation can help to predict the implications of anthropogenic disturbance on ecosystems. This “dynamic food web approach” is rarely applied at the coastal margin where aquatic and terrestrial systems are coupled and human development activities are often concentrated. Authors Alexander Tewfik, (USF Integrative Biology), Susan Bell, (USF Integrative Biology), Kevin McCann, (Univ. of Guelph, Guelph, Ontario, CA), and Kristina Morrow, (USF Integrative Biology) proposed a simple model of ghost crab (Ocypode quadrata) feeding that predicts changing dominant prey (Emerita talpoida, Talorchestia sp., Donax variablis) along a gradient of beach morphology and tested this model using a suite of 16 beaches along the Florida, USA coast. Assessment of beaches included quantification of morphological features (width, sediments, slope), macrophyte wrack, macro-invertebrate prey and active ghost crab burrows. Stable isotope analysis of carbon (13C/12C) and nitrogen (15N/14N) and the SIAR mixing model were used to determine dietary composition of ghost crabs at each beach. The variation in habitat conditions displayed with increasing beach width was accompanied by quantifiable shifts in ghost crab diet and trophic position. Patterns of ghost crab diet were consistent with differences recorded across the beach width gradient with respect to the availability of preferred micro-habitats of principal macro-invertebrate prey. Values obtained for trophic position also suggests that the generalist ghost crab assembles and augments its diet in fundamentally different ways as habitat morphology varies across a highly dynamic ecosystem. Their results offer support for a functional response in the trophic architecture of a common food web compartment (ghost crabs, macro-invertebrate prey) across well-known beach morphologies. More importantly, their “dynamic food web approach” serves as a basis for evaluating how globally wide-spread sandy beach ecosystems should respond to a variety of anthropogenic impacts including beach grooming, beach re-nourishment, introduction of non-native or feral predators and human traffic on beaches. Their study is published in the journal PlosOne.
Authors Carol Rizkalla, Earl McCoy, Eric Britt, and Henry Mushinsky, (USF Integrative Biology) examined the effects of sampling intensity, season, and planned burning on indirect monitoring of the rare Florida Sand Skink (Plestiodon [Neoseps] reynoldsi) using cover boards. Their study was carried out initially within 18 400-m2 enclosures replicated across three fire return intervals, so that we could estimate population density with simulated removal trapping. They installed cover boards at three densities (six replicates each). Sampling intensity influenced number of recorded presences (distinctive trails under the cover boards) and the rate at which the first presence was recorded. As a result, they recommend that cover boards be installed at a density of at least 200/hectare. Infrequent sample occasions prevented the application of robust occupancy models, so they repeated the study using 36 enclosures and daily observations of cover boards. Their results indicated that indirect sampling does not reflect population size with reasonable certainty and that fire return interval influences occupancy. The authors suggest that managers note the habitat structure when they interpret monitoring results. More presences were recorded during the spring, and the authors recommend that monitoring be confined to that season. Managers interested in detecting population changes of Florida Sand Skinks over relatively short periods of time must rely on direct monitoring with pitfall traps and possibly employ mark-release-recapture methods. Their study is published in the journal Herpetological Conservation and Biology.
In January Stephanie Gervasi, Sarah Burgan, Nathan Burkett-Cadena, Aaron Schrey, Hassan Hassan, Tom Unnasch and Lynn (Marty) Martin presented a talk titled “Vector preferences and host defenses in the West Nile virus system: A role for avian stress hormones?” at the annual meeting of the Society for Integrative and Comparative Biology in Portland, Oregon. Their research showed that significantly more blood was taken by mosquitos from birds that exhibited stress than birds not expressing stress hormones in their blood. Their studies went on to show that mosquitos fed on blood from birds under stress lay more eggs, and lay them more quickly after feeding, implying that mosquitos feeding on stressed populations of animals produce larger populations of mosquitos more rapidly, spreading disease more rapidly. Read more about their research here.
CONGRATULATIONS TO OUR FALL 2015 GRADUATES!
Christy Foust - Ph.D. (Richards/Harwood labs)
Nate Goddard - Ph.D. (Crisman lab)
Samantha Wilber - M.S. (McCoy/Mushinsky lab)
We wish you all the best in the future, and great success along the way!