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White-nose Syndrome (WNS), a disease causing over-winter mortality of hibernating bats, is caused by the psychrophilic fungus Pseudogymnoascus destructans (Pd) which was introduced to upstate New York in 2006. Cutaneous epidermal infection with Pd results in erosions and lesions in the epidermal wing tissue, which causes a decrease in torpor bouts typical of WNS. The little brown bat (Myotis lucifugus) is susceptible to Pd infection however the big brown bat (Eptesicus fuscus) has not shown increased WNS mortality despite equal exposure to Pd. As the epidermis is the site of infection epidermal analysis between the species is warranted. The mammalian epidermis contains free fatty acids (FFA), some of which have been shown to have antifungal properties as part of the innate mammalian immune system. Analysis of E. fuscus and M. lucifugus epidermal FFA, as well as pre- and late hibernation FFA analysis in M. lucifugus was performed. E. fuscus epidermis contains significantly greater levels of myristic acid and oleic acid and decreased levels of pentadecanoic and stearic acid levels compared to M. lucifugus. Pre- and late hibernation comparisons in M. lucifugus revealed significant differences in all FFA except palmitic acid. Laboratory propagation of Pd on different FFA media found that increased levels of unsaturated FFA, linoleic and oleic acid, inhibited Pd growth compared to saturated FFA. Pd colonies grown on media simulating FFA content of E. fuscus were significantly smaller than those grown on media resembling M. lucifugus. These results suggest the FFA content of bat epidermis could be useful in identifying which hibernating species may be more susceptible to Pd infection which will become important as Pd spreads throughout both Canada and the United States.

Humans have transformed natural landscapes in many ways that degrade ecosystems. Increase in urban growth leads to fragmentation of natural patches (Alberti 2005), which disrupts the landscape connectivity that can facilitate ecological processes such as migration and dispersal of organisms (Bierwagen 2006). Streams are ecosystems that are closely linked to their surroundings, through nutrient and energy flows derived from the watershed (Hynes 1975). Thus, both agriculture and urbanization, often adjacent to freshwater sources, can influence species distributions in stream ecosystems by degrading water quality and altering habitat (Warren et al. 2000, Allan 2004, Elmore and Kaushal 2008). For example, Walser and Bart (1999) observed a positive relationship between agriculture and sedimentation in streams in the Chattachoochee River system of the southeastern USA; this sedimentation is a leading cause of decreases in suitable fish habitat and fish egg survival (Berkmen and Rabeni 1987).

Bryophytes (mosses, liverworts, and hornworts) are a vital component of many headwater streams, where they often form the dominant plant communities (Vitt et al. 1986). Few other habitats are dominated by bryophytes. Even mire communities, where bryophytes form most of the ground layer, include many vascular plant species that make up a significant portion of the community biomass (Slack and Glime 1985). In headwater streams, bryophytes are often the most productive autotrophic organisms, accounting for a significant portion of in-stream primary production (Stream Bryophyte Group 1999). Furthermore, aquatic bryophytes can have substantial impacts on ecosystem function, including hydraulic, nutrient, and trophic dynamics (Stream Bryophyte Group 1999), making an understanding of the variables driving their abundance and composition vital to the conservation of these systems (Cattaneo and Fortin 2000).

Combining molecular analyses with natural history and ecology data can increase our understanding of the different factors that might affect island populations, and hence, to improve their conservation strategies and population management as well.

Climate change is a major environmental concern and one of the greatest threats to biodiversity (Williams et al. 2008, Bellard et al. 2012). Climate experts agree that the earth is warming at a rate faster than should be expected naturally, and that human practices are driving these and other climatic changes (Crowley 2000, Karl & Trenberth 2003, Solomon et al. 2007). Current change is resulting in an increase in global temperatures, greater variability in precipitation, and an increase in the intensity and frequency of extreme climatic events such as droughts, floods, and hurricanes (Peterson et al. 2012). Climate modeling predicts an increase in global temperatures and a continuation of its associated effects through the coming century (Solomon et al. 2007, Williams et al. 2008), while ecological projections suggest that these changes will have major consequences for global biodiversity and may potentially lead to a mass extinction event (Hannah et al. 2002, Brook et al. 2009, Bellard et al. 2012)

Biological invasions are of increasing concern due to the many negative consequences often associated with them, including reduced biological diversity (Wilcove et al. 1998, Pimentel et al. 2005), altered ecosystem properties and processes (Gordon 1998) and an estimated $120 billion per year in the United States in management costs and associated damages (Pimentel et al. 2005). There are a number of important traits shared among many invasive species that aid in their successful invasion. These traits include the ability to grow in disturbed habitats, high reproductive success (such as high seed production), rapid growth to its reproductive stage and the ability to disperse easily (Baker et al. 1965, Baker 1974). There are also a number of factors that make a habitat more prone to invasion, such as fragmentation, disturbance, excess nutrients and soil contamination (Marvier et al. 2004).

Anthropogenic activity has greatly altered ecosystem productivity and functioning through effects on regional and global climate changes (IPCC 2011). These changes, including increasing atmospheric CO2 concentrations ([CO2 ]) and temperatures, changes in precipitation patterns, and increased N deposition, can alter C, N, and P cycling in ecosystems by directly and indirectly affecting plant material entering the soil (O’Neill and Norby 1996, Norby 1998, Norby et al. 2001), and the rate at which this plant material is decomposed into dissolved organic matter and available nutrients. Further, changes associated with global change have been shown to accelerate decomposition processes and nutrient cycling (Vitousek et al. 1997, Rustad et al. 2001, Kelley et al. 2011).

An organism's niche is the ecological space that it occupies (Hutchinson 1957). Inthe absence of other species, a species may utilize the full range of biotic and abioticresources that it needs to survive and reproduce (Hutchinson 1957). However,competition for limited resources between ecologically identical entities will lead to theextinction of one or more species (Gause 1934, Hardin 1960, Levin 1970). Stable co-existence of different species may occur if, over time, competition and natural selectionresult in niche differentiation and, therefore, different resource and habitat use(MacArthur and Levins 1964, Schluter 1994). The partitioning of resources results innarrower ecological niches for competing species. The narrowed niche that a speciesoccupies as a result of competitive interactions is its "realized" niche (Hutchinson 1957,Schoener 1974, Morin 1999)

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Primary productivity and the availability of food resources have traditionally been understood as the key factors limiting consumer productivity in aquatic food webs (Wetzel 2001). However, this idea has recently been challenged by studies suggesting that the biochemical composition and quality of food resources may be of greater importance to trophic connectivity and the efficiency of energy transfer into biomass across the plant-animal interface (Sterner and Hessen 1994, Brett and Mtiller-Navarra 1997, Miiller-Navarra et al. 2000, Rosemond et al. 2000, Urabe et al. 2002, Hill et al. 2010). Food webs that lack key biochemical components within primary producers demonstrate trophic decoupling, leading to a significant increase in primary productivity but with little corresponding increase in consumer biomass (Brett and Mtiller-Navarra 1997). Food quality may be one reason why hypereutrophic lakes with large algal blooms sustain relatively few macroinvertebrates and fish. Algal species that dominate these systems (primarily cyanobacteria) contain inadequate nutrition to support higher trophic levels (Mtiller-Navarra et al. 2004).

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The Kv1 subfamily of voltage-gated potassium channels (Kv1.1-Kv1.6) is involved in repolarizing the membrane potential after an action potential, shaping the action potential, and neurotransmitter release. The ability to carry out these functions requires proper trafficking and localization to the cell surface. Kv1 subfamily members have very different trafficking and TGG patterns despite having very similar amino acid sequences. Both positive and negative amino acid trafficking determinants of these processes have been mapped to the outer pore-forming region, which differ in these channels. The two important amino acid determinants responsible for those differences have been identified by lab personnel. Using a site-directed mutagenesis approach to make targeted substitutions, I have defined the physical and chemical properties at those two key positions that affect the Kv1.4 potassium channel's localization pattern and TGG. The mutations were characterized by their effect on levels of surface and total protein, protein stability, and on cellular localization. It is hypothesized that the trafficking determinant on the channel's outer pore-forming region exerts its effect by binding a trafficking factor that causes either high partial intracellular retention or trafficking through the secretory pathway. Members of the Kv1 subfamily have very similar amino acid sequences. Kv1.1 and Kv1.4, for instance have 74.0% similarity over their core region. However, Kv1.1 and Kv1.4 homomers display different cell surface expression levels and TGG efficiencies when assembled as homomers in transfected cultured cell lines. Alterations in either parameter are predicted to affect cell signaling. When cotransfected into the same cell lines, Kv1.1 and Kv1.4 assemble into heteromers in which Kv1.1 acts in a dominant negative manner to reduce cell surface expression of the heteromers compared with Kv1.4 homomers. Both Kv1.1/Kv1.4 heteromers and Kv1.4 homomers have been observed in brai

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This study presents the karyotypes of 13 species of cardinalfishes and demonstrates the efficacy of using cytogenetics as an appropriate tool for generating cladograms of phylogenetic relationships. It was found especially useful in gaining insight into the relationships among cardinalfishes at the supraspecific, interspecific and intraspecific levels. In particular, it proved useful in reevaluating the present provisional classification of the family and pointed toward a needed revision of some of the genera which were based on osteological and swimbladder characteristics. The chromosome characters were also useful in partially resolving the species interrelationships within the genus Apogon. Further, it was found that many of the cardinalfishes showed intraspecifc variation in chromosome number and type, as well as clear indications of naturally occurring hybrids among the various chromosomal morphs within the population. Also indicated was the presence of clearly designated sex chromosomes. These data have bearing on the recognition of unit stock, as well as having phylogenetic and biogeographic significance.

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