9421427 Banks Rapidly advancing biotechnology affords new opportunities for increasing the power and productivity of environmental biology. This research will apply cutting-edge biotechnology towards the resolution of previously insoluble environmental problems. Specifically, advanced DNA-based biomolecular techniques will be developed to identify and quantify cryptic species and trophic interactions at an unprecedented level of precision. Quantitative estimation of DNA concentration using the polymerase chain reaction (QPCA) is currently being incorporated into a highly replicable automated technique which facilitates application to difficult questions. This research will test whether recent developments in this technique, already being successfully applied to biomedical questions, enable reliable estimation of population sizes of two strains of bacteria (Escherichia coli). Density estimates will be evaluated for E. coli populations on plates with known different ratios of two strains. These will be compared with results obtained from gut extractions of a bactivorous nematode (Caenorhabditis elegans) fed on replicate E. coli plants. Positive results would indicate that these procedures not only estimate population sizes, but also estimate trophic flows from different prey species to their predators. When possible, estimates such as these are currently extremely difficult and involve radioactive reagents. This development will avoid such hazardous reagents and use the latest equipment and procedures to increase the ease and the statistical power in such determinations. %%% Recent work has employed more highly resolved trophic data to overturn several long held beliefs about food-web structure and offers more successfully predictive hypotheses in their place. These novel analyses of microscopic trophic interactions will assist further advances in trophic ecology. Beyond trophic interactions, this technique will likely have broader application since they may be used to quantify DNA extracted from water, soil, and other ecologically important environments. The species-specific population and biomass estimates that these procedures may enable will greatly enhance our ability to address new and long-standing basic and applied issues concerning ecosystem, community, and population ecology of microbes, fungi, and micrometazoans.
