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Ecosystem Engineering by Net-Spinning Caddisflies (Hydropsychidae) In Rocky Mountain Streams
No full textEcosystem engineering is a ubiquitous process by which organisms modify physical habitat characteristics and influence patterns of biological organization. Often, modification of physical environments by ecosystem engineers can facilitate other organisms by creating habitats for species that would otherwise be absent. Despite the potentially wide reaching consequences of facilitation through ecosystem engineering, many facets remain poorly understood in stream ecosystems. Here we present a synthesis of ecosystem engineering by hydropsychid caddisflies and describe how they affect stream macroinvertebrate communities. Hydropsychid caddisflies are a globally distributed group of net-spinning insects that live in stream gravel beds and have high abundances across western Montana. Hydropsychid caddisflies act as ecosystem engineers because their silk structures alter sediment transport conditions and local flow patterns of streambeds. Using lab experiments and field surveys, we show that ecosystem engineering by caddisflies changes physical templates of streambeds and influences other members of the macroinvertebrate community. We found that caddisfly nets increase the shear stress required to initiate gravel movement for gravels up to 70 mm. Additionally, we found that caddisfly silk structures substantially alter local flow at the streambed surface by reducing velocity by 70%. Furthermore, we have found that the presence of net-spinning caddisflies markedly increases local abundances and biomass of other stream macroinvertebrates across environmental gradients. Taken together, these findings indicate that caddisflies impart substantial physical changes to streambed habitats that have ecologically significant consequences for stream macroinvertebrate communities. Our findings indicate that caddisflies influence ecological processes from physical habitats to biological community structure and could act as important controls of Rocky Mountain stream ecosystems
Effects of Familiarity on Mate Selection in Poecilia reticulata
No full textPoecilia reticulata (commonly known as guppies) are freshwater fish commonly used in behavioral research. Originating from South America, this species can be purchased locally in the United States. We investigated the effect of familiarity on female mate selection. Our research consisted of individual female guppies each paired with two male guppies, from separate schools of fish, which were bred at MSUB (Fig. 1). Preceding each experiment, one female was familiarized with one male in a divided fish tank. Uniform experiments were then conducted by placing a female guppy in a sectioned fish tank with the familiar male and a second unfamiliar male. Both males were placed on either side of the female. Following each trial, the individual female would be familiarized with the male that was not familiarized in the previous trial. Results were concluded by calculating time intervals that a female guppy spent near either male guppy or in the middle of the experimental fish tank. To record live behavior, with least amount of stress, a video recorder was used to record the guppies. To show effects of familiarization on female guppy choosiness, familiarizations were alternated monthly between a selected pair of males and one female. In these data there is a trial that suggests female mate preference may be influenced by familiarity
Failure to Detect Anti-Viral Activity by Prokaryotic Argonaute Proteins
No full textArgonaute (Ago) proteins are present in all three domains of life and are involved in nucleic acid guided silencing and interference pathways. The well-studied Eukaryotic Argonautes (eAgo) form the catalytic core of the RNA interference (RNAi) pathway that is involved in gene silencing, transposon silencing and antiviral defense. Limited research on Prokaryotic Argonautes (pAgo) suggests these proteins are involved in defense against foreign genetic elements such as plasmids. pAgos have been hypothesized to defend against bacteriophage, however no direct evidence has been found so far. Here, we report the failure to detect antiviral defense mediated by pAgos against various Escherichia coli bacteriophages. We overexpressed 8 phylogenetically diverse prokaryotic Argonaute proteins in Escherichia coli BL21 (DE3) and challenged them with 7 bacteriophages spanning the Myo-, Sipho-, and Podoviridae families. No antiviral activity was detected that could be attributed towards the pAgo proteins. However, up to 100,000-fold reduction in viral infectivity was observed for 2 phages that correlated with plasmid-based protein expression. The mechanism through which this antiviral activity is mediated is unknown and subject for future study
Ligand K-Edge Study of M(Pdtc)L Complexes
No full textCarbon tetrachloride is a known carcinogen that can cause cancer related illnesses when it is dechlorinated by Cytochrome P450, located in the human liver. Environmental reduction of carbon tetrachloride can produce lesser chlorinated intermediates, such as the trichloromethyl radical, which is harmful to living organisms. [Cu(PDTC)L]- has shown to be able to dechlorinate carbon tetrachloride so that it will produce CO2 and chloride, which are environmentally safe compared to lesser chlorinated intermediates. The mechanism between [Cu(PDTC)L]- and carbon tetrachloride is poorly understood. This study links the dechlorination reactivity of a series of [M(PDTC)L]- complexes (L = Cl-, CN-, and PPh3 and M = Cu and Ni) to the individual electronic structures of each complex by using sulfur k-edge. We find that reactivity of a given [Cu(PDTC)L]- species is linked to the lability of L in a given solvent rather than to the relative covalency of the M-S bond in each species
Student Engagement While Establishing Classroom Mathematical Practices
No full textThere is a significant connection between student engagement and performance achievement. Klem and Connell write, “student engagement has been found to be one of the most robust predictors of student achievement and behavior in school, a conclusion which holds regardless of whether students come from families that are relatively advantaged or disadvantaged economically or socially” (2004, p. 5). However, student engagement is complex, and currently relationships to outcomes such as mathematical understanding and learning are elusive (Fredricks, Blumenfeld, & Paris, 2004; Middleton, Jansen, & Goldin, 2017). This study investigates student engagement while learning through use of an app that collected student engagement reported by participants during a classroom teaching experiment. This paper discusses preliminary results on students’ engagement in the process of learning. Though not anticipated, we observed differences between male and female students’ engagement while working in mixed-pairs worthy of investigation. In particular, we observed differences between male and female students’ engagement while working in mixed-pairs surrounding important mathematical contributions from female partners. Female students described situations in which they perceived of male partners overlooking valuable contributions towards completing tasks, resulting in dips in engagement. With, regards to data collection, the app and survey effectively gathered information on student engagement, which was triangulated by students’ descriptions in recall interviews
The Effects of Surfactants in Glyphosate-Based Herbicides on The Spotted Salamander
No full textSpotted Salamander (Ambystoma maculatum) populations have been declining worldwide. There are many reasons that are thought to be contributing to this decline, one being the use of agricultural herbicides. Glyphosate-based herbicides are one of the most commonly used herbicides worldwide and their use is continuing to increase. Originally it was thought that glyphosate was the toxic ingredient causing declines in amphibian populations; however, studies are indicating that the surfactants used in these herbicides are what is responsible for the toxicity. The purpose of this study is to evaluate the toxicity (48 h) of a silicon-based surfactant on the spotted salamander compared to the surfactant in Glystar Plus®. The two experimental groups will be exposed to a solution containing 41%glyphosate with varying concentrations of a silicon based non-ionic surfactant at 14% and 28% respectively at an application rate of 0.35 mL/m2 added to Glystar Original®. Toxicity will be evaluated by comparing length, girth, weight, liver somatic index, and physical appearances
Coordinated Regulation of Stem Cell Proliferation and Differentiation by Rna-Binding Proteins Cooperating with Ccr4-Not Deadenylase Complex in C. Elegans
No full textUncovering molecular mechanisms regulating the balance of stem cell proliferation and differentiation can help us understand the causative factors for ageing, cancer and various degenerative disorders. Pumilio and FBF (PUF) family RNA-binding proteins are highly conserved regulators of stem cell development. We are investigating how PUF proteins regulate proliferation and differentiation of stem cells using C. elegans as a model organism. FBF-1 and FBF-2, two PUF family proteins in C. elegans, are required for maintaining germline stem cells by translational repression of their target mRNAs (Crittenden et al., 2002). FBF-1 and FBF-2 are very similar in primary sequence and share target mRNAs (Prasad et al., 2016, Kershner et al., 2010 and Porter et al., 2018), but we found that they have differential effects on target mRNAs and maintained stem cell numbers. Our findings suggest that FBF-1 may destabilize target mRNAs while FBF-2 may protect targets from degradation; FBF-1 may slow stem cell proliferation and differentiation whereas FBF-2 may promote stem cell proliferation and differentiation in coordinate fashion. Additionally, we found that FBF-1 activity in stem cells requires CCR4-NOT deadenylase machinery that shortens poly (A) tail of mRNA leading to mRNA instability. By contrast, FBF-2 activity in stem cells shows less dependence on CCR4-NOT, which is related to FBF-2 interaction with its specific cofactor, DLC-1. We propose that FBF-1, but not FBF-2, interacts with CCR4-NOT complex in stem cells. We are going to test this hypothesis by performing proximity ligation assay. In conclusion, our study uncovered mechanisms of PUF proteins controlling stem cell proliferation and differentiation through differential cooperation with CCR4-NOT deadenylase machiner
The Influence of Antimicrobial Peptides, Cutaneous Microbial Communities and Water Quality on The Susceptibility of Columbia Spotted Frogs (Lithobates Luteiventris) To Chytridiomycosis
No full textChytridiomycosis is a potentially deadly skin disease found in amphibian populations all over the world. Chytridiomycosis is caused by the fungus Batrachochytrium dendrobatidis (Bd) that grows on the skin of amphibians. The fungus can cause a disruption in the homeostatic functions of the amphibian skin and can lead to death. The relationship between an amphibian’s antimicrobial skin secretions, cutaneous microbial communities and environmental water quality can affect their resistance and susceptibility to Bd infection. Columbia spotted frogs (Lithobates luteiventris) are native to western Montana and have been affected by chytridiomycosis. Three lakes known to be positive for Bd were used as collection sites where a total of ten frogs were caught on three different occasions throughout the summer for a total of 90 collected samples. Each frog was swabbed for bacterial and fungal samples and placed in a solution that would collect antimicrobial peptides secreted from the frogs’ skin. Water samples were collected at each site and analyses were performed to assess various parameters. Early results suggest that AMPs may affect the relative abundance of an important anti-fungal bacteria (Rhizobacta) which influenced Bd status. The goal of the ongoing research is to determine what parameters of environmental conditions, antimicrobial skin secretions, and cutaneous microbial communities allow Columbia spotted frogs to be resistant to chytridiomycosis in order to better predict and treat future outbreaks
Beyond Words: Thought - A Visual Attempt to Inspire Thoughts on the Climate Crisis (Poster)
No full textThe climate crisis presents unprecedented challenges to the wildlife profession, as it does for all of humanity. Does the human animal have the capacity to wrap its mind around it? This poster is an attempt to convey and inspire individual thoughts about the climate crisis where words in scientific or popular literature may fail us, and from individual thoughts may arise actions and initiative beyond our experience. For actions beyond our experience are required of those who strive to make a difference, and of others who would hope to support, rather than impede, their efforts. So, we hope that the visual image of this poster will speak to someone for whom words are not as impactful
Montana's Greater Sage-Grouse Conservation Strategy All Hands Balancing Conservation and Development Across All Lands
No full textThe Greater Sage-grouse (Centrocercus urophasianus or GRSG) inhabits sagebrush grassland habitats exclusively and shares habitat with up to 300 other species. Montana is a key stronghold among the western states. Montana’s emphasis on habitat conservation on public and private lands is foundational to supporting and growing Montana outdoor economy. The Montana Sage Grouse Conservation Strategy, implemented by the Montana Sage Grouse Habitat Conservation Program (Program), blends voluntary incentives with regulatory oversight through the permitting process and a new requirement to mitigate for impacts to designated habitat. The Program implements the Greater Sage-Grouse Stewardship Act and Executive Order 12-2015. Key pillars include: 1. a consultation process to guide development; 2. grants to maintain, enhance, restore, and expand habitat; and 3. mitigation to offset impacts of development. Taking an “all lands, all hands” approach, the Program works collaboratively with private landowners, state agencies, and federal land management agencies. Since 2015, the Program has reviewed nearly 1500 proposed development projects in designated GRSG habitat on public and private lands. Approximately 43,148 acres have been placed in perpetual conservation easements through Sage Grouse Stewardship Fund grants. With the goal of no net loss-net gain preferred, the mitigation system incorporates market-based incentives and a Habitat Quantification Tool to quantify gains and losses of functional habitat due to conservation or development projects, respectively. Successful conservation depends on proactive stewardship of the remaining intact sagebrush landscape. Montana is well-positioned for the range-wide conservation assessment set for 2020