Environmental Science & Ecology.
Zebra mussels are an invasive species introduced into the Great Lakes from Europe in 1986. Since then, they have spread aggressively throughout the eastern United States and have had a significant impact on Great Lakes ecology and biodiversity. Samples have been taken from many sites throughout the Great Lakes in order to assess genetic diversity and population substructure in Michigan. Tissue from over one thousand samples has been frozen over the past five years, including specimens from the Great Lakes, as well as inland lakes and rivers. DNA was extracted from frozen samples and PCR was used in order to amplify five polymorphic loci. The PCR products were checked on agarose gels and analyzed using the CEQ 8000 automated DNA analysis system from Beckman-Coulter. Fragments sizes were determined and genotypes identified using internal reference standards. The parameters investigated include number of alleles per locus, observed and expected heterozygosity, population substructure and genetic distance. The preliminary results reveal a great amount of genetic variation in Great Lakes Zebra mussels. Future studies will concentrate on gene flow and genetic divergence between populations. The results have important implications for bioremediation efforts in the Great Lakes.
Impacts of the Rainforest and the Effects of Rainforest Depletion. Ariel Fray, University of Michigan--Flint
The rainforest is an important resource with many benefits. Not only does it provide the Earth's atmosphere with oxygen and rain, but it also regulates the climate, shelters half of the world's plant and animal species, and provides a home for indigenous tribes ("Rainforest"). New pharmaceutical uses of the plants of the rainforest are being discovered constantly. However, the rainforest is being depleted through deforestation, agricultural policies, and other causes that threaten the very existence of this key resource. We are currently burning over 200,000 acres of rainforest daily ("Rainforest"). This paper will focus on the benefits of the rainforest, the causes of its growing depletion and potential solutions to help resolve the problem. Direct effects of rainforest depletion will be the extinction of the numerous plant and animal species, as well as the indigenous inhabitants. In addition, indirect effects include an imbalance in gases which may lead to global warming, as well as a loss of potential cures to serious diseases.
The Influence of Two Alkylphenols on Development, Growth, Reproductive Behavior, and Survival of Juvenile and Adult Crayfish. Steven J. Gauthier and Daniel A. Bergman, Grand Valley State University, Department of Biomedical Sciences
Invertebrates make up the greater part of the world's biological diversity and are present in almost all habitats, and consequently used as biological indicators for pollution. Human activities and exposure to various pollutants have become a severe threat to invertebrates. Crayfish are one such important invertebrate that is affected by chemical pollutants such as pesticide/herbicide runoff and industrial waste effluents. Crayfish are keystone species in most aquatic systems, because they are an important resource for other animals and can alter species diversity and abundance. Crayfish are also raised for human food consumption in the aquaculture industry. For these reasons, crayfish are important organisms to study and better understand the effects of pollution on their physiology and behavior. Alkylphenols are chemicals used in various laboratory detergents and in pesticide formulations, making them frequent pollutants in aquatic systems. Bioaccumulation of these chemicals in the tissues of crustaceans, fish, and birds is becoming widespread. We examined the effect of exposure to recommended sublethal levels of two alkylphenol pollutants (nonylphenol and octylphenol) on crayfish development, growth, reproductive behavior, and success finding food. We found numerous significant impacts on many aspects of crayfish life when exposed to alkylphenols, including significant mortality increases for juvenile crayfish.
The Influence of Adrenocorticotropic Hormone on Dominance Relationships between Male Electric Fish, Brachyhypopomus pinnicaudatus. Arthur Martin, Saginaw Valley State University, Jacqueline Torres, Florida International University, Philip Stoddard, Florida International University
Melanocortin peptides influence EOD waveforms of weakly electric fish. It appears that electric fish use these signals during social interactions to communicate social behavior, status, and sex. Gymnotiform electric fish have already shows circadian enhancement of the EOD waveform that they generate during interactions. EOD changes occur in response to social and environmental changes. Adrenocorticotropic hormone (ACTH) is a melanocortin peptide that can increase the amplitude and duration of the electric signal waveform of the electric fish Brachyhypopomus pinnicaudatus. In vivo injections of ACTH were administered to male fish. Two males were in a tank were behaviorally recorded for a period of four days to record their social behaviors and EOD signals. The injections were administered at the same time each day to one of the male conspecifics. The injections each day were rotated between the two males to observe for dominance shifts influenced by the ACTH. The recorded EOD signals and social behaviors will be coupled and analyzed to determine the influence ACTH has on social aggression and the relationship EOD signals exhibit on dominance structure.
DNA Fingerprinting of Michigan Migratory Waterfowl: Mallards and American Black Ducks. Christi Raines, Gail Kantak and David J. Stanton, Saginaw Valley State University, Department of Biology
Migratory waterfowl are an important component of wetland ecosystems and an important recreational resource in Michigan. The geographic ranges of the American Black Duck and Mallard overlap extensively. However, the range of the American Black Duck is currently shrinking due to habitat loss and possible hybridization with Mallards. The long-term viability of the American Black Duck populations depends in part on the degree of genetic variation found in the populations. This in turn depends on demographic parameters and details of the breeding structure. In order to assess genetic diversity and the degree of interspecific hybridization, DNA fingerprinting was performed. DNA was extracted from feathers using a Qiagen DNeasy kit. Templates were amplified by PCR using primers to highly polymorphic loci. Products were checked on agarose gels and then sized to determine genotype using the Beckman Coulter CEQ 8000 genetic analysis system. The parameters evaluated include number of alleles, observed and expected heterozygosity and genetic differentiation between species. The results reveal evidence of extensive and continuing hybridization between these two species and are concordant with previous studies on Atlantic flyway populations. The results also have important implications for management strategies involving Michigan migratory waterfowl.
Insect Mitochondrial Gene Order. Lisa Sharko and David J. Stanton, Saginaw Valley State University, Department of Biology
Mitochondrial gene content and gene order are highly conserved in animals. Indeed, most arthropods share a similar gene order and most crustaceans and insects have an identical gene order. However, some variation in mitochondrial gene order has been detected within certain insect groups such as Orthoptera. Since such variation is rare, rearrangements can serve as valuable markers for phylogenetic reconstruction in the groups where they are found. In order to screen for variation in mitochondria gene order, we have designed and constructed PCR primers that anneal to conserved regions within insect mitochondrial DNA. These primers allow for the amplification of five gene junctions that collectively contain seventeen of the twenty two mitochondrial tRNA genes, including junctions known to be hot spots for gene rearrangement events in insects. By screening for size variation, we can detect possible gene rearrangements which can then be confirmed by DNA sequencing. So far, we have detected size variation at one junction for bumblebees and cicadas. The phylogenetic utility of these variants is being assessed by screening other members of these groups. We are also screening many Orthoptera species, in order to determine the distribution of the gene order variation observed in previous studies.
The Distribution of Crayfish Species in the Tributaries of the Grand River, MI. Norrissa M. Thomas and Daniel A. Bergman, Grand Valley State Univ., Dept. of Biomedical Sciences
Large numbers of invertebrate species are under severe threat of extinction due to the extreme transformations of habitats by human activities or introductions of invasive species. Crayfish are an important invertebrate species under ecological pressure. They are considered keystone species in most aquatic ecosystems. Keystone species are organisms that are pivotal in shaping the ecology of an ecosystem. Crayfish are an important food source for predators and can affect species diversity and abundance of smaller organisms. Specifically, crayfish can adversely affect systems by removing plants from aquatic systems, making the water turbid. They also prey on fish eggs, reducing their numbers. There are over 415 species of crayfish in North America. It is recognized that at least eight species are found in the state of Michigan. One of these species is the invasive rusty crayfish that has been introduced to some of Michigan's waterways and has had detrimental impacts on aquatic life in those systems. We sampled the Grand River drainage system to document the crayfish species present. Our study identified three species of crayfish in the Grand River system, as well as, the invasive zebra mussel that could alter crayfish populations, but no rusty crayfish to date.
"The Asian Brown Cloud": South Asian Atmospheric Pollution and Its Devastating Effects. Kaitlin Trainor, University of Michigan--Flint
The growing problem of the Atmospheric Brown Cloud over Southern Asia has led to serious environmental, agricultural and health effects in the region. The cloud mass, which is three kilometers thick and the size of the continental United States, contains various microscopic particles and invisible gasses emitted mainly from coal combustion and biomass burning. The pollution cloud was discovered in 1999 when Veerabhadran Ramanathan and a team of 200 international researchers launched the Indian Ocean Experiment (INDOEX) to measure pollutants over South Asia. In the end, it was determined that the manmade contribution to the Asian Brown Cloud is about 85%, which suggests that humans are almost totally responsible for the current pollution crisis. In addition, the cloud affects one fifth of the global population and is capable of traveling halfway around the world in less than one week. Experts believe that this long distance travel of particulate pollution has caused as much as half of the world's artificial warming, and if current trends continue, disaster is inevitable. This paper will examine the causes and effects of the pollution cloud as well as possible solutions to the problem.
Effects of Serotonin on Muscular Activity of Orconectes rusticus. Lucinda Wenzlick and Arthur Martin, Saginaw Valley State University
The purpose of this experiment is to measure the effects of serotonin on the muscular activity of crayfish, Orconectes rusticus specifically. Serotonin is a neurotransmitter that is known to have inverse effects on invertebrates and vertebrates. Specifically in crustaceans, serotonin has been shown to affect numerous functions such as hormone release, heart rate, and neural and muscular activity. Increased serotonin levels within crustaceans have been shown to cause aggressive postures and decreased retreat behaviors during agonistic encounters. The model crayfish is innervated by incredibly few excitatory axons, making them a strong model organism to study serotonin induced behavior. The influence serotonin exhibits on crayfish behavior will be measured by analyzing walking speed; time spent moving, and turning angle relative to the food source. Trials will be conducted in a customized flow tank which will evenly emit the odor of fish gelatin throughout the tank. All trials will he video recorded and analyzed using Peak Mows. Research has analyzed the effects of serotonin on crustacean agonistic behaviors, but relatively little research has identified its effects on muscular activity. Our current hypothesis is that serotonin will increase the rigidity of muscular activity and decrease walking speed and rate of movement.
The Role of Habitat in the Reduction of Salamander Populations in the United States. Melissa Babcock, University of Michigan--Flint
Habitat is essential for the population of salamanders to thrive. Salamander habitats currently include wetlands, areas near rivers and streams, and areas in agricultural fields, as well as woodlands. The contamination of these habitats, as well as the reduction of the original habitat has played an important role in reducing the numbers of salamanders in these habitats. In some cases, the salamander population is approaching possible extinction. This paper will focus on the reduction of salamander populations, and will focus especially on the role of habitat in this depletion. It will also consider what strategies are being used in order to reduce this problem and help protect the salamander populations from endangerment and even extinction.
Growth Rates of an Exotic Invasive Earthworm, Amynt has Hilgendorfi, in a Temperate Forest. Cassandra R. Belcher, Holly G. Greiner, and Scott D. Tiegs, Oakland University, Department of Biological Sciences
Amynthas hilgendorfi is an exotic invasive earthworm of Asian origin that has recently been reported in the Great Lakes region. While the ecological effects of European earthworm species have been documented, those effects associated with A. hilgendorfi are relatively unknown. We measured growth rates of A. hilgendorfi, a measure of resource acquisition potential, and compared them to those of better-studied earthworm species. We collected A. hilgendorfi from the field regularly during their growing season, and estimated the biomass of individuals using an allometric equation. We observed that A. hilgendorfi growth rates were exponential, and high relative to published values for other species, even compared to those obtained in controlled laboratory settings. A. hilgendorfi accumulated 7.65 mg fresh mass per day on average, similar to the 7.63 mg/day growth rate of the invasive earthworm, Lumbricus rubellus, a species known to have significant impacts on native forests. This finding, coupled with field observations of often-high population densities, suggests that A. hilgendorfi has the potential to become an established and influential member of soil communities.
Carbon Cycling in Muskegon Lake: Insights on Driving Forces. Angela Defore and Bopi Biddanda, Grand Valley State University, Annis Water Resources Institute
Freshwater ecosystems are highly reactive sites of carbon metabolism, and the terrestrial-aquatic-atmosphere link is a key component of the global carbon cycle. However, studies quantifying the annual seasonal cycle of nutrients and carbon by autotrophic and heterotrophic communities in production and respiration in freshwater aquatic environments are seriously lacking, but crucial to our understanding of the carbon cycle. Beginning in February 2009, changes in lake metabolism, associated environmental variables, and the trophic relationship between phytoplankton and bacterioplankton were investigated to identify events and time frames in which Muskegon Lake becomes a source or sink of carbon. Discrete and continuous measurements of production and respiration were applied to give a complete representation of community metabolism and the rate at which these communities control energy flow, nutrients and organic matter storage. Results indicate production/respiration ratios first rise to 2.4 then fall to 0.42 over the growing season. Experimental additions of nitrogen and phosphorus stimulated production in the summer months. Dissolved organic carbon selectively stimulated R approximately 2 fold during all seasons. Studies of lake metabolism may provide a useful holistic indicator of lake response to changing environmental conditions and contribute to our understanding of the role of lakes in the carbon cycle.
Effects of the Exotic Asian Earthworm, Amynthas Hilgendorfi, on a Temperate Forest Ecosystem. Holly G. Greiner and Scott D. Tiegs, Oakland University, Department of Biological Sciences
While invasive earthworms of European origin have documented impacts on temperate forests, those of a recent invader belonging to the Asian genus Amynthas are virtually unknown. To fill this knowledge gap, we conducted a replicated manipulative field experiment consisting of 1.5 [m.sup.2] enclosures in which we placed either Amynthas hilgendorfi, or Lumbricus rubellus (a well-studied European species), both species together (to look for interactive effects), or no earthworms as a control. We evaluated the response of soil-aggregate size, soil-carbon content, and leaf-litter mass loss. Plots containing A. hilgendorfi had a greater proportion of large (>2mm) soil aggregates and greater soil carbon content, while L. rubellus plots remained similar to controls. However, leaf-litter mass loss in A. hilgendorfi plots did not differ significantly from controls, while L. rubellus plots did. These findings, coupled with some peculiar life-history traits of A. hilgendorfi, suggest that its effects may differ from European earthworms. Current understanding of earthworm invasions stems almost entirely from studies of European species belonging to the family Lumbricidae, which may be of limited applicability to understanding the ecological effects of taxa from other regions on temperate forests.
PBDEs in Lake Huron Fish. Elizabeth Hanna-Tromp, Rick Rediske and Jim O'Keefe, Grand Valley State University, Annis Water Resource Institute
Polybrominated diphenyl ethers (PBDEs) are used as flame retardants on a variety of products such as textiles, building materials, electronics, furnishings and plastics. Past and continued use has caused their residues to become ubiquitous environmental pollutants. Because of their ability to act as endocrine disrupters, PBDEs are a concern for human health. Lake Huron and the other Great Lakes fish have been shown to accumulate elevated levels of PBDEs which causes concern for people who eat fish from this area. BED congener patterns are impacted by dietary and regional changes although some patterns are found in many areas and in many different types of fish. BDE-47 is the dominant congener found in fish overall. This may be due to debromination of other highly brominated congeners. Fish were collected from two sites in Lake Huron during the summer months of 2006. They were analyzed for 9 common PBDE congeners using negative chemical ionization GC-MS. The highest level of PBDE congeners were found in common carp (232 ng/g) and walleye (31 ng/g). These data will assist in the development of environmental fate and transport estimates for PBDEs.
Algal Responses to Road Run-off Collected from an Urbanized Catchment. Kelli A. Johnson and Alan Steinman, Grand Valley State University, Annis Water Resources Institute
Road run-off containing excess nutrients, heavy metals, and other contaminants often flows directly into streams during storms, impacting both water quality and stream ecosystem structure and function. This run-off is a potential stressor or stimulant for algae. We conducted two (June 2008 and July 2009) controlled experiments in mesocosms (~1,300 liter tanks) to evaluate the effect of storm water on algal biomass, metabolism and community composition. Storm run-off was collected from Little Black Creek, MI and used to create the following treatments: 0% storm water (control; n=4), 50% (n=4), or 100% (n=4). Nested within each mesocosm were exclosure treatments containing different combinations of algae, snails (Physa sp.) and Pumpkinseed Sunfish (Lepomis gibbosus). Storm water concentration did not significantly impact algal biomass or metabolism in either experiment. Algal community composition in the 0% storm water treatment was significantly different from the 100% treatment at the end of the experiments. Within the 0% storm water treatment only, significantly less biomass was present on tiles exposed to snails, suggesting that snail grazing was inhibited in the presence of storm water. The limited algal response in these experiments may be because the storm water run-off used in this experiment contained low levels of contaminants.
PCB and PBDE Levels in Lake Michigan Whitefish. Amanda K. Potter, Richard R. Rediske, and James P. O'Keefe, Grand Valley State University, Annis Water Resources Institute
Persistent Bioaccumulative Toxic Chemicals (PBTs) continue to pose a threat to human and environmental health in the Great Lakes basin. Polybrominated diphenylethers (PBDEs) and polychlorinated biphenyls (PCBs) are considered the most significant toxic chemicals in the Great Lakes ecosystem. In this study, Lake Whitefish (Coregonus cluspeaformis) were collected in Lake Michigan, near Muskegon, Michigan using monofilament gill nets and a semiballoon bottom trawl during April--November, 1998-2001. Soxhlet extractions with hexane were performed on whole Lake Whitefish and PCB and PBDE congeners were measured by negative chemical ion mass spectrometry. Total PCB and PBDE levels were positively correlated with length of Lake Whitefish where summer 20-22 inch whitefish had the highest amounts of PBDEs (177 ng/g) and 22-24 inch whitefish had the highest total PCB concentrations (771 ng/g). These findings will aid in the development of a future risk assessment and possible fish consumption limits.
Investigating the Effectiveness of Active-and Cooperative-Learning Strategies in the Biological Sciences: Are They Equally Beneficial to Non-Majors and Biology Majors Alike? Preliminary Findings. Amanda J. Ross, Saginaw Valley State University, Dept. of Biology
After investigating multiple peer-reviewed sources, it is apparent that various active- and cooperative-learning approaches to teaching complex topics in the biological sciences at the introductory collegiate level are effective strategies when compared to strictly traditional lecture-based methods. However, whether these non-traditional approaches are equally effective at teaching similar topics to non-majors versus science majors is not well documented. This project will determine if there are any statistically significant differences in the pretest and posttest examination and evaluation scores in two undergraduate biology classes: Biology 105A, a general education course for non-science majors, and Biology 111A, an introductory course designed for students pursuing a degree in the health or science fields. The first portion of this project took place during the fall of 2009 academic semester. This phase incorporated two cooperative-teaming projects into the classroom and evaluated the influence these projects had on overall comprehension and appreciation for learning. An upcoming semester will utilize traditional lecture-style teaching approaches to the same topics and, again, will evaluate overall understanding and satisfaction. By comparing the effectiveness of different teaching and learning strategies, we may develop a better understanding of how active- and cooperative-learning methods may affect overall achievement, regardless of students' academic majors.
Integrated Nutrient Assessment of Bear Lake, Michigan. B.T. Scull, R.R. Rediske, and K.A. Thompson, Annis Water Resources Institute, Grand Valley State University
An integrated assessment of nutrient loading was conducted in the Bear Lake watershed. Bear Lake is a 1.66 [km.sup.2] eutrophic drowned river mouth system that is included in the Muskegon Lake Area of Concern. The lake is scheduled for a Total Daily Maximum Load (TMDL) due to excessive nutrients and nuisance algal blooms. A ten fold increase in the loading of suspended sediment and phosphorus was noted from base flow to storm event conditions. Loadings from the tributaries were enhanced by a channelized stream and highly modified wetlands near the inlet to Bear Lake. While storm events accelerated phosphorus loading to Bear Lake, the presence of heavy cyanobacteria blooms, elevated chlorophyll-a concentrations, and low Secchi disk depth readings throughout the summer were indicative of an internal sediment loading source. An analysis of sediment and water quality, bathymetry, and thermal profiles determined that sediment re-suspension also was a significant source of nutrient loading. In addition, the Long-Term Hydrologic Impact Assessment Model was employed to estimate NPS loading from lake front property.
Temperature Tolerance of a 'New' Composting Earthworm, Eisenia Hortensis, as a Means of Assessing Its Invasibility in Temperate Forests. Andrew M.T. Stonehouse, Holly G. Greiner and Scott D. Tiegs, Oakland University, Department of Biological Sciences
While composting earthworms have traditionally been of tropical origins and unable to persist in cold climates outside compost bins, a European species, Eisenia hortensis has recently become prevalent in the vermicomposting industry. E. hortensis' European origins suggest that it could survive cold temperatures, and may therefore be able to overwinter in temperate forests. Other exotic European earthworm species have undesirable impacts on temperate deciduous forests, and the addition of species to invasive communities tends to compound these effects. We compared the survivorship of commonly used tropical composting species (Eisenia fetida and Perionyx excavatus), at a near-freezing temperature (1.5[degrees]C), to E. hortensis and a well-established invasive European earthworm species (Lumbricus rubellus). The traditional composting species experienced significant mortality within 24 hours. In contrast, the European E. hortensis survived the near-freezing temperature treatment for the duration of the experiment (6 days), as did L. rubellus. These results suggest that E. hortensis has the potential to overwinter in temperate zones and become an established member of earthworm communities, with unknown consequences for forest ecosystems.
A Dying Legend: The Plight of the Sumatran Tiger. Jennifer N. Ross, University of Michigan--Flint
The tiger is an animal that has long been shrouded in myth and legend. Even in areas where the tiger does not naturally exist, it commands respect and awe, even reverence. Why, then, are tigers, especially the Sumatran tiger, in such danger of extinction? The endangerment of the Sumatran tiger is an issue exclusively located on the island of Sumatra, Indonesia, yet it is a critical issue that will result in the loss of yet another tiger subspecies if it remains unsolved. Fewer than 500 Sumatran tigers remain with less than 400 left in the wild. The Sumatran tiger suffers from increasingly smaller areas of environment suitable for inhabitation due to illegal logging and large commercial plantations. Poachers also reduce the population even more, commonly harvesting tiger body parts to sell to black market dealers. Various measures--such as the Basic Forestry Law, tiger farming, and a government-instituted forestry program--have been implemented in an attempt to preserve the Sumatran Tiger population. In this paper, I will examine the history of the conflict, causes of the tigers' endangerment, and both unsuccessful and current measures implemented in an attempt to preserve the tiger population.
Ultrastructure of the Development of the Mitochondrial Derivatives in Bittacus stigmaterus Sperm. Brock Humphries, Kathleen Pelkki, David Stanton, and Sally Shepardson, Saginaw Valley State University, Department of Biology
During the spermatid stage of sperm development, mitochondria undergo an extensive metamorphosis to form two mitochondrial derivatives. Clusters of mitochondria fuse and form a bipartite structure which eventually separates into two halves. These transformed halves elongate and orient themselves on either side of the developing axoneme. The derivatives become a major component of the mature sperm flagellum. The distinct stages of coalescence, bipartite mass (nebenkern), onion, loaf, and mitochondrial derivatives will be discussed, as will the placement of the two mitochondrial derivatives in the mature sperm.
Evaluating Wildlife Responses to Climate Change in North America. Kelly Thortnan, University of Michigan--Flint
Climate change, whether anthropogenic or natural, has and will continue to have an effect on the sustainability of North American wildlife. Changes in temperature have been proven to affect the habitats and physiological attributes of the globe's wildlife and plant populations. Concern has been raised due to the recent rapid increases in global temperatures and global warming trends have been blamed for the recent extinction of the Golden Toad of South America (Brennan). Four major effects of rising temperatures on wildlife species have been observed. These factors involve changes in phenological events, genetics, morphology and the trend for wildlife species to move pole-ward or to higher elevations in response to rising temperatures. As a reaction to these factors many past wildlife species have been able to adapt; however, the recent, drastic climate changes influenced by human activities are pushing many species to their limits. This paper will focus on several of the many North American wildlife species responding to climate change including the loggerhead sea turtle (Caretta caretta), the pika (Ochotona princeps), and the purple finch (Carpodacus purpureus).
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|Date:||Sep 22, 2012|
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