Browsing Graduate School by Issue Date "2014-08-27"
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- ItemAssessment of the Presence and Fate of Pharmaceuticals and Personal Care Products (PPCPs) Found in Treated Wastewater Discharges into Charleston Harbor, South Carolina(2014-08-27) Hedgespeth, Melanie Lea; Wirth, Edward F.; Burnett, Louis E.; Pennington, Paul L.; Sapozhnikova, Yelena V.Pharmaceuticals and personal care products (PPCPs) are a group of contaminants of emerging concern that are introduced into aquatic environments by non-point and point sources. This study assessed seasonal/regional trends of targeted PPCPs detected in samples from two local wastewater treatment plants (WWTPs) and surface water from the Charleston Harbor over twelve months. After modifying EPA Method 1694 to include hormones, analysis using HPLC/MS/MS revealed that of the 19 target compounds examined, 11 were quantified above method reporting limits in wastewater influent, 9 in effluent, and 7 in surface water samples. Concentrations were reduced by > 90% for most chemicals in effluent compared to influent, though concentrations of some PPCPs in effluent were higher than those in influent. Differences in effluent concentrations and estimated removal between WWTPs are believed to be related to variation in general operating parameters and/or the anoxic basin employed by one of the facilities. Laboratory experiments also examined the effects of salinity on PPCP recovery/degradation and PPCP effects on oxygen uptake in Eastern oyster (Crassostrea virginica) gill tissue. Results indicate that there may be little to no risk for acute effects on non-target organisms, though further testing of sublethal exposures and/or mixtures is warranted. Overall, future monitoring of PPCPs may aid in minimizing potential negative impacts of increasing urban/industrial development in coastal regions.
- ItemCharacterization of Fatty Acids in Blubber and Thoracic Appendages of Pygmy and Dwarf Sperm Whales (Kogia breviceps and Kogia sima)(2014-08-27) Goodson, Abby M.; McFee, Wayne; Broadwater, Margaret; Keppler, Charles; Murren, Courtney; Seaborn, GloriaPygmy sperm whales (Kogia breviceps) are the second-most commonly stranded cetaceans along the Southeast coast of the Unites States, yet very little is known about their basic biology. Blubber fatty acids and lipid class composition have not been fully described in this species, and may supply valuable baseline data that could provide insight to the health, diet, and metabolic processes of this species. Approximately half of the pygmy and dwarf sperm whales (Kogia sima) that strand along the southeastern U.S. coast suffer from a heart disease known as cardiomyopathy; the etiology of this disease in cetaceans remains unknown. Lipid content (gravimetrically), lipid class composition (TLC∼FID), and fatty acid composition of triacylglycerols and wax esters (GC/FID) were characterized in blubber samples from stranded pygmy and dwarf sperm whales with and without cardiomyopathy. A prominent visceral fat deposit located adjacent to the lung has also been consistently observed in K. breviceps during necropsy and where available, these appendages were also examined. K. breviceps blubber samples were lower in lipid (49.6 +/- 2.5%, mean +/- SEM) than K. sima (70.2 +/- 1.5%), and K. breviceps animals had higher wax ester content in blubber (92.6 +/- 2.3%) than K. sima (47.9 +/- 9.5%). Wax ester content increased with length in K. sima animals, and species differences could not be fully evaluated due to length differences between K. sima and K. breviceps used in the study. Thoracic appendages consisted of almost entirely wax esters. The most abundant blubber fatty acids were 18:1n∼9, 16:0, and 16:1n∼7 and these accounted for 62% of the total fatty acids in both species. Differences in fatty acid profiles were detected between the two species, as well as between internal and blubber lipids, but no differences were found between diseased and non-diseased animals. Fully understanding the biology of an animal is critical to its population viability and is necessary to ensure the presence of these species for future years.
- ItemEcosystem Perspective: Temporal Analysis of the Reef Fish Assemblage in Southeast U.S. Atlantic Continental Shelf Waters(2014-08-27) Stratton, Mark; Reichert, Marcel; Kucklick, John; Plante, Craig; Stephen, JessicaOf the myriad species inhabiting live-bottom reefs off the southeast U.S. Atlantic coast, many are economically valuable finfish species in the snapper-grouper management complex. The majority of these species are managed based on single-species (SS) assessment models, which do not parameterize important variables such as interspecific trophic interactions and environmental impacts (among others). These shortcomings of SS assessments, along with the overexploited status of multiple stocks in the complex and the inherent multi-species nature of the fishery, lend cause for more holistic assessment and management approaches for this fishery. Towards this goal, the current study applied ecosystem indicators to monitor the status of the reef fish assemblage from Cape Lookout, NC to Cape Canaveral, FL (13-60 m depth). Utilizing a 20-year dataset (1990-2009) from a fishery-independent baited trap survey, temporal analysis for all species combined revealed a consistent increase in mean fish size but an overall decrease in the number of fish and total biomass (i.e. there are now fewer, but larger fish in the system). Changes in metrics describing the biomass-size spectrum also indicate temporal shifts in the distribution of fish biomass towards larger size classes. While overall reef fish biomass has decreased, the percentage of community biomass comprised of especially marketable species ("targeted" stocks) has increased. Collective results from size- and production-based indicators are consistent with concomitant fishery-dependent trends, which show a decrease in commercial harvest of reef fishes since 1990 (primarily due to implemented size and catch restrictions). Importantly, temporal decreases in overall biomass highlight the necessity to consider gear selectivity when interpreting time series. Mean community δ¹⁵N (a trophic level proxy), rarefied annual species richness, and annual species heterogeneity (Simpson's index⁻ₑ) showed no overall change from 1990-2009. Future exploratory assessments of reef fishes should emphasize aggregate species approaches, a concept that has already materialized in some management regulations.
- ItemFresh Food Access and Lower-Income Populations in the Charleston, SC Tri-County Area(2014-08-27) Fantry, Regan; Stewart, Kendra; Jos, Philip; Mills, LindekeSouth Carolina is currently second in the nation in hunger. As rates of public and private food assistance program utilization have risen, lower-income populations have been left behind in the movement towards organic and local fresh food economies and utilization. For these populations, the acquisition of any food is the priority. This causes lower-income populations to possibly experience health problems due to the cheaper and easier to acquire nature of energy-dense, high calorie foods versus more expensive, harder to acquire fresh food options. Several organizations in the Charleston tri-county area are focused on bridging the gap for these lower-income populations, providing more access to fresh food grown in the lowcountry. Case studies of three organizations: Fields to Families, Metanoia Community Development Corporation, and the Lowcountry Food Bank examine how each organization meets this need, gaps in service, and desired changes and support to improve access and organization success.
- ItemGenetic and Environmental Contributions to Gene Expression Variations in the Eastern Oyster (Crassostrea virginica) from Three Locations in Mississippi(2014-08-27) Johns, Christopher David; Chapman, Robert W.; Zimmerman, Anastasia M.; Sotka, Erik E.; Kingsley-Smith, PeterThe role of the contribution of genetics to variations in gene expression has not been well studied. Studies on gene expression often attribute variation in gene expression to differences in environmental parameters while ignoring that population structure or random genetic variation could also be associated with the differential expression. To address this, 25 Eastern oysters (Crassostrea virginica) were sampled from each of three sites in Mississippi. Two of the sites were located within urban watersheds, while the other was located within a forested watershed. Water quality parameters were measured at each sampling site. The expression of 5,573 oyster genes derived from an expressed sequence tag (EST) library was measured in each oyster using a long oligo microarray. Genetic data were collected using eight previously described microsatellites. A machine-learning method, Artificial Neural Networks, with sensitivity analysis was used to determine the percent contributions of the environmental and genetic input factors toward variations in gene expression. Genetic variation was found to explain 12.22% of the gene expression variation across the 5,573 genes surveyed. Further cluster analysis revealed a small group of 28 genes that had a genetic contribution toward variation in gene expression as high as 38.72%. These results support the premise that genetic variation affects gene expression and should be taken into account in future environmental genetics studies. This study has also identified a group of potential genes for the development of biosensors.
- ItemImpacts of Social Networking Sites in Real Life: Is the Profile a Tool of the Real Life Self?(2014-08-27) Melissa, Grossman; Kopfman, Jenifer; Davis, Julie; Benigni, VincentPeople actively engage in identity management every day to present the self that is most desirable to a particular audience. The Internet has created a unique environment of anonymity, which allows identity experimentation with multiple selves. Social networking sites provide a nonymous environment, which still maintains some aspects that encourage identity exploration, but with a level of accountability that is reflected in users' real lives. This study utilized an anonymous online survey, examining how social networking site users engage in audience management as a way of conducting personal online identity experiments and identity re-creation in real life as a direct result of feedback received online. Results show users actively engage in audience management through privacy settings and experience real life changes as a result of social networking site activities.
- ItemImplications of Emerging Neoliberal Politics on Conservation Governance in the South Carolina Lowcountry(2014-08-27) Skaggs, Katherine Anne Sanders; Watson, Annette; Mills, Lindeke; Snyder, Marcia; Benefield, JustinWhile developers, government officials, and even many conservation organizations are pushing for neoliberal approaches to achieve key conservation goals, critical scholars raise serious questions about market-based solutions to environmental conservation. They question whether these approaches may be encouraging unsustainable rates of resource consumption that may lead to the destruction of environments. These scholars also question the ways in which neoliberalism transforms local understandings of, uses of, and access to rural assets. Yet little attention has been paid to the neoliberalizaton of conservation governance within advanced capitalist contexts. This paper examines neoliberal conservation governance strategies in the private sector of the United States. By interviewing stakeholders, analyzing project documents, planning processes, and census data, we compare the approaches of for-profit and non-profit conservation efforts in South Carolina's Lowcountry. In both cases, the goal is to conserve natural resources and preserve rural livelihoods for future generations while encouraging "smart" development. That is, each project tries to conserve critical habitats, natural resources, and cultural landscapes, while also stimulating new business investment. The paper explores whether for-profit and non-profit conservation efforts, both relying on market-based approaches, produce different kinds of conservation landscapes, and the ways in which their goals are achieved within a neoliberal framework. I suggest that through the design of East Edisto, a type of Creative Class, a "Nature Class," entrepreneurs, labor and industry are being targeted and drawn to the Lowcountry. Thus I develop a better understanding of the role key participants play in constructing these new forms of conservation governance and cultivate a better understanding of how the current politics and social relations of the region may shape future regional economic and residential development of the Lowcountry. This study has implications for the ways political ecologists and other critical nature-society scholars think about the costs of putting a price on nature within advanced capitalist contexts.
- ItemIntelligent Selection of New Data for Ranking Algorithms(2014-08-27) Boyer, Kirk A.; Langville, Amy; Cox, Ben; Smirnov, Oleg; Mitchener, GarrettAlgorithms that rank items using paired comparison data are becoming increasingly widely applicable. New data is always being gathered to try to improve their ability to make predictions. I demonstrate that it is possible to seek data in such a way that the predictive ability of algorithms will improve without attention to the particular content of the data, present two methods of doing so, and discuss the kinds of algorithms to which they are applicable. In addition, I introduce an alteration to the Colley Matrix  rating algorithm that allows it to include equally-matched comparisons (ties) in a meaningful way.
- ItemLanguage of Clothes: Nonverbal Communication Intention and Misinterpretation(2014-08-27) Elizabeth A., Dorrance; Ferrara, Merissa; Ferguson, Doug; Kopfman, JeniferClothing is a primary nonverbal cue from which assumptions are made in first impressions. Clothing is an important part of the identity construction process and its ability to transmit immense meaning and messages allows clothing to serve as a major component in forming judgments of others. The present study employed an experimental quantitative design featuring participant clothing creation via the internet and aimed to discover the discrepancies between clothing message intention and interpretation by others. Results from 211 participants showed that message creators tend to view their clothing message and projected image as more successful, intelligent, friendly, charming, cultured, likeable, extroverted, attractive, active, trustworthy, impulsive, and practical than the message receiver. Also, the "Trendy" style messaging is more accurately interpreted than "Preppy," "Classic," or "Relaxed/Casual" styles. Interpretation of results including Communication Accommodation Theory and media effects are discussed. Recommendations for future nonverbal clothing code messaging studies are made.
- ItemNektonic Use of Intertidal Eastern Oyster Reefs (Crassostrea virginica) in South Carolina Estuaries(2014-08-27) Joyce, Ryan; Kingsley-Smith, Peter R.; Reichert, Marcel J.M.; Arnott, Stephen A.; Roumillat, William A.; Harold, Antony S.For the past decade, oysters have been recognized as "ecosystem engineers" that generate important ecological services, including habitat provision for nektonic organisms (e.g., adult finfish, certain crustaceans). Most previous studies investigating this role of intertidal oyster reefs in South Carolina have compared the nektonic assemblages on natural oyster reefs, saltmarshes, mud bottom and subtidal oyster shell habitats using various methods which involve some degree of habitat disturbance. The present study employed a novel, non-destructive sampling method involving the deployment of a drop net around study plots to compare the nektonic assemblages associated with intertidal oyster reefs (natural and enhanced) with those of neighboring soft sediment habitats at three sites in South Carolina. Each site comprised an experimental plot, which contained an oyster reef varying in substrate type (oyster "castles", oyster shell bags, and natural oyster reef) and age (1 to 7 years), and an adjacent control plot without structural complexity. Abundances of nektonic organisms were higher in experimental plots compared to control plots and were correlated to surface seawater temperature at all locations in the experimental plot. Species richness was significantly higher within the experimental plot than within the control plot at two of the three study sites. At the remaining site, the number of species did not differ significantly between treatments. Differences in diversity between treatments across sites may be explained by habitat age.
- ItemPersistent Organic Pollutants in Shark Blood Plasma from Estuaries along the Southeast US Coast(2014-08-27) Bazan, Katie L.; Kucklick, John; Keller, Jennifer; Strand, Allan; Gelsleichter, JamesPersistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), pose a potential threat to marine organisms because of their resistance to degradation and ability to bioaccumulate in the environment. Hydroxylated metabolites from compounds like PCBs may also disrupt the endocrine system of organisms when they are retained in the blood stream. Bonnethead (Sphyrna tiburo) and finetooth (Carcharhinus isodon) sharks inhabit coastal estuaries during the spring and summer months along the southeast US coast leaving them exposed to organic pollutants. The current study examined POPs and their hydroxylated metabolites in the blood plasma of 69 bonnethead and 30 finetooth sharks from South Carolina and Georgia estuaries. The bonnethead sharks caught in St. Simons Sound, GA contained the highest concentrations of PCBs and their hydroxylated metabolites. Specifically, 4-OH PCB 187 and 4'-OH PCB 172 were found in shark blood along with 6-OH PBDE 47. The finetooth sharks caught in Bulls Bay, SC contained roughly five times higher mean concentrations of PCBs than the bonnethead sharks caught from the same location. Bonnethead sharks caught in St. Simons Sound, GA were shown to have PCB concentrations in blood at levels comparable to those observed in bottlenose dolphins (Tursiops truncates) blood from Sarasota, FL. This indicates that more study is needed for the bonnethead sharks in the St. Simons Sound estuary and that contaminants in shark blood reflect known gradients of habitat contamination. In addition, blood can be collected from sharks in a non lethal manner which is important given that many shark stocks are being depleted and that, outside this study, there have been no systematic assessments of organic contaminant accumulation in sharks.
- ItemPhotographic Evidence of Temporal and Spatial Variation in Hardbottom Habitat and Associated Biota of the Southeastern U.S. Atlantic Continental Shelf(2014-08-27) Glasgow, Dawn M.; Reichert, Marcel; Sedberry, George R.; Harris, Scott; Stephen, Jessica A.This study was designed to develop a standardized habitat characterization scheme to classify benthic habitats in the southeastern U.S. Atlantic continental shelf. For integration with other classification schemes, this scheme incorporates current federal classification standards with modifications based on information derived from digital images taken with chevron trap-mounted cameras during the Marine Resources Monitoring, Assessment and Prediction program (MARMAP) 2009 fish trapping survey. Classifications were based on dominant geologic (e.g. surface substrate, morphology and relief) and biotic components (e.g. biota, growth patterns, and percent cover) that could most accurately be determined from images. The data were used to create habitat location maps with ArcGIS. Two examples were provided for utilizing the scheme to: (1) examine changes in benthic habitats over time; and (2) observe species interactions with specific habitat components. Mean percent biotic cover was used to detect changes in benthic habitat in areas representing three depth zones (Charleston inshore, mid, and outer shelf) where repetitive sampling occurred between 1990-1993 and 2006-2009. A statistically significant change in mean percent cover over time was detected in the Charleston inshore habitat only. To identify species and habitat component interactions, associations between the presence of invasive Indo-Pacific lionfish (Pterois spp.), mean percent cover, and vertical relief were examined. Categorical data analysis showed a statistically significant association between lionfish and areas with vertical relief. Also, a baseline catch per unit effort (CPUE = Sigma lionfish observed in each collection / Sigma trap camera collections) was calculated for all lionfish present in all image collections (CPUE = 0.08); per shelf depth zone (inner shelf = 0, mid shelf = 0.01, outer shelf = 0.23, and shelf break = 0); and per level of vertical relief (none = 0.03, low-moderate = 0.20, and moderate-high = 0.27), providing one of the first estimates of relative abundance of lionfish in the region. This thesis provides baseline information to assist fisheries managers in utilizing trap cameras and GIS to move towards a habitat characterization standard. The data can be used as a tool to observe spatial patterns, to assess trends and relationships in habitats and associated faunal assemblages, to aid in the identification of essential fish habitats, and to assist managers with marine spatial planning decisions.
- ItemPostsecret Par Avion: An International Analysis of Anonymous Self-disclosure(2014-08-27) Diebolt, Maggie; Kopfman, Jenifer; Ferrara, Merissa; Ruth-McSwain, Amanda; McCandless, AmyIn an era in which individuals are essentially available at all hours of the day via personal communication devices and social networking sites, some are opting to share their secrets with complete strangers, rather than those listed on their speed dial. With hundreds of thousands of submissions and nearly 384,000,000 site visits since its inception in 2004, PostSecret.com has transformed from a small community art project into an international medium for anonymous self-disclosure. This exploratory study compares personal and cultural themes presented by secrets displayed weekly on the American and French PostSecret blogs over the course of one year, along with the perceived efficacy of and interest in anonymous self-disclosure by monitoring the visitor tracking tool on each website. Content analysis results indicate a significant difference between American and French reactions to the PostSecret project through the number of secret submissions and site visits, though both sites exhibit shared secrecy themes.
- ItemPredictive Capabilities of GIS for the Distribution of Specialist Wetland Skippers (Lepidoptera: Hesperiidae) in South Carolina(2014-08-27) Smith, Thomas P.; Scholtens, Brian; Levine, Norman; Everett, Jean; Lord, LisaLittle is known about the wetland specialist skippers (Lepidoptera: Hesperiidae) that are indigenous to the lower coastal plain of the southeast United States. The intermittent occurrence of these species across their range may be due to the elusive lifestyles and rarity of many of the species within this group. This is the first attempt to correlate specific wetland types from a GIS layer with known occurrence data of these skipper species within the limits of the lower coastal plain of South Carolina. These data show two groups of wetland specialist skippers: one specific to palustrine emergent wetlands (Group 1) and the other to palustrine forested wetlands (Group 2). These specific wetland types were checked for new records of these species in order to ground-truth initial predictions, and these data were combined to re-analyze the correlations of wetland types with species using a logistic regression. Those wetland types deemed significant due to their correlation with the occurrence data were then tested by randomly splitting the entire dataset into training and testing datasets that provided scores of accuracy based on the predictions of the wetland types. Group 1 species were well predicted based upon this single map layer, but Group 2 species could not be related to the wetland types used to predict their occurrence. The results suggest that the forested wetland category within the map layer is so widespread and too vaguely defined to pinpoint the habitat requirements of Group 2, while the much less common habitat type used to predict Group 1 seemed to be a good indicator of the occurrence of those species. The occurrence of common species also proves to be a valuable indicator of the presence of the less common species. The habitat requirements of each species are discussed individually.
- ItemRestoration of Maritime Habitats on a Barrier Island Using the Painted Bunting (Passerina ciris) as a Flagship Species(2014-08-27) Latshaw, Sarah Ann; Nolan, Paul; Jodice, Patrick; Jones, Martin; Mills, LindekeHabitat loss and degradation are major causes of the decline of many songbird species. One species, the Painted Bunting (Passerina ciris ) has seen declines of over 60 percent from 1966--1995, according to Breeding Bird Surveys, mostly due to habitat losses. Because of this decline, the Painted Bunting has become high priority by many conservation organizations. Collaborating with the Kiawah Island Conservancy, and several Biologists, we used radio telemetry technology and vegetation sampling techniques to: 1) determine habitat use, 2) identify home range and territory size, and 3) create vegetation recommendations for the Kiawah Island Conservancy. We captured a total of 58 buntings representing all sexes and age classes between May--August 2007--2010, and tracked daily until the transmitter battery failed. Vegetation samples were also taken, measuring ground cover, midstory structure, and canopy cover. Buntings used maritime forest, maritime shrub, and developed land use types at significantly higher rates than the other land use types (F = 65.6, df = 314, p = ≥0.001). The top 10 substrates frequented most often by the buntings from 2007--2010 were: 1) Live Oak (Quercus virginiana), 2) Wax Myrtle (Myrica cerifera), 3) unknown, 4) Slash Pine (Pinus elliottii), 5) Eastern Red Cedar (Juniperus virginiana), 6) Loblolly Pine ( Pinus taeda), 7) Seaside Oxeye (Borrichia frutescens), 8) snag, 9) shrubs, and 10) Yaupon Holly (Ilex vomitoria). Painted Buntings mean home range size (calculated from MCP) was 7.1+/-1.1 ha, and mean territory (calculated from kernel density) was 0.3+/-0.03 ha. Recommendations from our research may not only impact the local bunting population, as well as on other wildlife, they may also have major conservation implications both statewide and regionally by demonstrating the feasibility of homeowner-financed habitat restoration.
- ItemRetention of Three Types of Tags Applied to Adult Red Drum (Sciaenops ocellatus)(2014-08-27) Hendrix, Carolyn; Denson, Michael R.; Ulrich, Glenn; Roumillat, Bill; Li, JiexiangTag loss is a vital component of survival estimates that are applied to abundance calculations as part of stock assessments. This study evaluated the retention and reliability of tags used on adult red drum in South Carolina waters. Sampling was conducted by the South Carolina Department of Natural Resources (SCDNR). Between 2001 and 2008, adult red drum (n=1986) were captured as part of an adult monitoring survey in South Carolina, using a bottom longline. Fish were measured, tagged with two external dart tags, implanted with an internal passive integrated transponder (PIT) tag, and fin-clipped for microsatellite genotyping. The retention of the nylon dart, the stainless steel dart, and the PIT tag were evaluated over an eight-year period. External tag retention was estimated using logistic regression and Bayesian analysis, and compared to a subsample of fish held in controlled saltwater recirculating tanks. Microsatellite matches were evaluated for use as accurate individual identifiers, or genetic tags, by using allele frequencies to calculate genotype match probabilities. PIT tag loss was detected by using matching microsatellite DNA genotypes to compare against PIT tag field records. Microsatellites reliably identified individual fish. With as few as five complete and matching loci the match probability was 6.36E-6. PIT tags had 100% retention throughout this study, and were retained for 2048 days in the wild. External tag retention in wild fish decreased significantly over time. Nylon dart tags were retained for approximately one year longer than stainless steel dart tags, and the two had significantly different retention over time at the 90% confidence level. Tag retention in tank-held fish did not vary significantly over time. Nylon dart tags were retained significantly longer in tank-held fish than in wild fish. This was the most complete tag retention study conducted on adult red drum along the coast of the Southeastern United States.
- ItemTransgenerational Plasticity in Yellow Monkeyflower (Mimulus guttatus): An Analysis of Maternal and Paternal Effects in Association with Edaphic Variation(2014-08-27) Henson, Christopher; Murren, Courtney; Pritchard, Seth; Rutter, Matt; Strand, AllanEdaphic conditions are an important component in the overall environment experienced by individual plants and their resultant progeny. For annual, sessile organisms, response to soil conditions and variability across generations is an essential element of living in a patchy environment. Transgenerational plasticity involves maternal or paternal induction of the offspring phenotype based upon the environmental conditions experienced in the parental generation and provides a possible response mechanism for variable environments across generations. To assess the presence of transgenerational plasticity in the form of maternal and paternal effects, three generations of Mimulus guttatus were introduced to chemical solutions mimicking the calcium and magnesium of serpentine and nonserpentine edaphic environments. Maternal effects were significant in early growth and persisted through reproduction. Paternal effects were significant only in early growth. Transgenerational plasticity therefore may provide an evolutionary mechanism for M. guttatus to respond to variable edaphic conditions across generations.