30 research outputs found

    Evaluation of a putative entomopathogenic Caenorhabditis (Nematoda: Rhabditid) and associated Serratia (Proteobacteria: Enterobacteriaceae)

    Get PDF
    A major goal of modern biology is to extend our understanding of biological systems investigated in the laboratory to their ecological and evolutionary context. With extensive understanding of the function, development and genetics of C. elegans, exploring the link between this laboratory model and the environment in which this system evolved would be very interesting because very little is known about the natural history of this premier model organism. A new strain of Caenorhabditis briggsae (SoAf) with an associated bacterium, Serratia sp. SCBI, has been isolated from South Africa using common entomopathogenic nematode trapping methods. This study taxonomically identified and evaluated entomopathogenic behavior of C. briggsae SoAf and Serratia sp. SCBI. Hemocoelic injections of Serratia sp. SCBI demonstrated pathogenicity in insect larvae, Galleria mellonella. Caenorhabditis briggsae SoAf and other Caenorhabditis, including C. elegans , were capable of infection, growth and reproduction within the insect larvae in the presence of Serratia sp. SCBI. Identification of a putative entomopathogenic C. briggsae expands on our understanding of Caenorhabditis ecology and provides a framework for further investigation of entomopathogensis in other free-living nematodes

    The nose knows: How tri-trophic interactions and natural history shape bird foraging behavior

    Get PDF
    THE ECOLOGICAL QUESTION Do two species of ocean-foraging birds detect and respond to a chemical cue which is linked to their food source, and how might differences in their natural history help to explain any variation in sensitivity? ECOLOGICAL CONTENT Foraging, trophic cascades, chemical ecology, behavioral ecology, Antarctic food webs WHAT STUDENTS DO This dataset is designed for first-year biology students, but can be altered for upper-level students. After receiving sufficient background on the biology of King penguins, students must make hypotheses regarding the penguins’ sensitivity to an odor known to be associated with the primary productivity of the ocean. Students are given multiple data sets and need to analyze the data using a variety of statistical tests. Students work in pairs to examine and analyze the data, and then as a group generate conclusions to develop the larger picture. To give students a chance to apply their knowledge beyond penguins, a second dataset with other seabirds is introduced. Here students must contrast the results of seabirds to this odor against the responses of King penguins. For successful completion of the assignment, students must recognize how differences in the natural history between the two groups of birds might impact their sensitivities towards the odor. SKILLS Hypothesis creation, statistical analyses, graph creation, graph interpretation, phylogenetic tree interpretation, manipulating datasets and formulas in MSExcel, MSPowerpoint slide creation, synthesizing knowledge, drawing conclusions STUDENT-ACTIVE APPROACHES Guided inquiry, cooperative learning, jigsaw, critical thinking ASSESSABLE OUTCOMES Hypotheses creation, statistical results using MSExcel, figure creation using MSExcel, slides produced using MSPowerpoint, answers to questions SOURCE Bonadonna, F., S. Caro, P. Jouventin, and G.A. Nevitt. 2006. Evidence that blue petrel, Halobaena caerulea, fledglings can detect and orient to dimethyl sulfide. Journal of Experimental Biology 209:2165-2169. Cunningham, G.B., S. Leclaire, C. Toscani, and F. Bonadonna. 2017. Responses of king penguin Aptenodytes patagonicus adults and chicks to two food-related odours. Journal of Avian Biology 48:235-242

    Sustainability and Justice: Challenges and Opportunities for an Open STEM Education

    Get PDF
    Open educational resources, or OER, are teaching materials that reside in the public do-main and are available under an open license. While the creation of high-quality materials and cyberinfrastructure to share these resources is important, OER are much more than static resource repositories. Vibrant OER communities function as collaboration hubs and often include librarians, instructional technologists, instructors, education researchers, funders, open-source software developers, and college administrators. Together, these in-dividuals work as a community to respond to changes in the education landscape, support student learning impacts both in terms of cost savings and student retention, and solve issues related to broadly sharing open resources on the web. This essay provides general information about OER, describes communities developing OER for science, technology, engineering, and mathematics education, and presents insights about sustainability chal-lenges. The sustainability challenges are organized according to multiple dimensions: cultural and social, economic and financial, and technological and environmental. In addition, OER provide important opportunities to address and promote social justice and open and accessible education philosophies. Knowing more about the OER landscape, sustainability challenges, and educational justice opportunities can help instructors use and contribute to this growing movement to reshape the landscape of undergraduate education

    Effects of Cu/Zn Superoxide Dismutase (sod1) Genotype and Genetic Background on Growth, Reproduction and Defense in Biomphalaria glabrata

    Get PDF
    Resistance of the snail Biomphalaria glabrata to the trematode Schistosoma mansoni is correlated with allelic variation at copper-zinc superoxide dismutase (sod1). We tested whether there is a fitness cost associated with carrying the most resistant allele in three outbred laboratory populations of snails. These three populations were derived from the same base population, but differed in average resistance. Under controlled laboratory conditions we found no cost of carrying the most resistant allele in terms of fecundity, and a possible advantage in terms of growth and mortality. These results suggest that it might be possible to drive resistant alleles of sod1 into natural populations of the snail vector for the purpose of controlling transmission of S. mansoni. However, we did observe a strong effect of genetic background on the association between sod1 genotype and resistance. sod1 genotype explained substantial variance in resistance among individuals in the most resistant genetic background, but had little effect in the least resistant genetic background. Thus, epistatic interactions with other loci may be as important a consideration as costs of resistance in the use of sod1 for vector manipulation

    The nose knows: How tri-trophic interactions and natural history shape bird foraging behavior

    No full text
    THE ECOLOGICAL QUESTION Do two species of ocean-foraging birds detect and respond to a chemical cue which is linked to their food source, and how might differences in their natural history help to explain any variation in sensitivity? ECOLOGICAL CONTENT Foraging, trophic cascades, chemical ecology, behavioral ecology, Antarctic food webs WHAT STUDENTS DO This dataset is designed for first-year biology students, but can be altered for upper-level students. After receiving sufficient background on the biology of King penguins, students must make hypotheses regarding the penguins’ sensitivity to an odor known to be associated with the primary productivity of the ocean. Students are given multiple data sets and need to analyze the data using a variety of statistical tests. Students work in pairs to examine and analyze the data, and then as a group generate conclusions to develop the larger picture. To give students a chance to apply their knowledge beyond penguins, a second dataset with other seabirds is introduced. Here students must contrast the results of seabirds to this odor against the responses of King penguins. For successful completion of the assignment, students must recognize how differences in the natural history between the two groups of birds might impact their sensitivities towards the odor. SKILLS Hypothesis creation, statistical analyses, graph creation, graph interpretation, phylogenetic tree interpretation, manipulating datasets and formulas in MSExcel, MSPowerpoint slide creation, synthesizing knowledge, drawing conclusions STUDENT-ACTIVE APPROACHES Guided inquiry, cooperative learning, jigsaw, critical thinking ASSESSABLE OUTCOMES Hypotheses creation, statistical results using MSExcel, figure creation using MSExcel, slides produced using MSPowerpoint, answers to questions SOURCE Bonadonna, F., S. Caro, P. Jouventin, and G.A. Nevitt. 2006. Evidence that blue petrel, Halobaena caerulea, fledglings can detect and orient to dimethyl sulfide. Journal of Experimental Biology 209:2165-2169. Cunningham, G.B., S. Leclaire, C. Toscani, and F. Bonadonna. 2017. Responses of king penguin Aptenodytes patagonicus adults and chicks to two food-related odours. Journal of Avian Biology 48:235-242

    Host Susceptibility is Altered by Light Intensity After Exposure to Parasites

    No full text
    corecore