1,346 research outputs found

    Visceral Beginnings

    Get PDF
    Editorial introduction for JCACS Volume 9, Number 1

    Attending to Particularity, Refusing the "Central Story"

    Get PDF
    This is the Editorial essay for Volume 9, Number 2

    Breeding Birds in Cedar Stands in the Great Dismal Swamp

    Get PDF
    The Great Dismal Swamp located in the coastal plain on the Virginia- North Carolina border, has long been recognized as a vegetationally distinctive region with many unusual geological and biological features. Formerly at least twice the currently estimated size of 85,000 hectares (Carter 1979), the Great Dismal Swamp is still shrinking because of a dropping water table caused by more than 200 years of logging, ditching, and other human activities. In 1973, the Union Camp Corporation donated a 19,871-hectare tract located near Suffolk, Virginia. to The Nature Conservancy, which transferred the land to the U.S. Fish and Wildlife Service. This parcel, all in Virginia and including the 1255-hectare Lake Drummond, became the core of the Great Dismal Swamp National Wildlife Refuge (hereafter, G.D.S.N.W.R.), established in 1974. The G.D.S.N.W.R. is still growing in size by the acquisition of land by purchase or by gift; by the end of 1980, it was 41,026 hectares, with 24 per cent (9866 hectares) in North Carolina

    Evolution of size-dependent flowering in a variable environment: construction and analysis of a stochastic integral projection model

    Get PDF
    Understanding why individuals delay reproduction is a classic problem in evolutionary biology. In plants, the study of reproductive delays is complicated because growth and survival can be size and age dependent, individuals of the same size can grow by different amounts and there is temporal variation in the environment. We extend the recently developed integral projection approach to include size- and age-dependent demography and temporal variation. The technique is then applied to a long-term individually structured dataset for Carlina vulgaris, a monocarpic thistle. The parameterized model has excellent descriptive properties in terms of both the population size and the distributions of sizes within each age class. In Carlina, the probability of flowering depends on both plant size and age. We use the parameterized model to predict this relationship, using the evolutionarily stable strategy approach. Considering each year separately, we show that both the direction and the magnitude of selection on the flowering strategy vary from year to year. Provided the flowering strategy is constrained, so it cannot be a step function, the model accurately predicts the average size at flowering. Elasticity analysis is used to partition the size- and age-specific contributions to the stochastic growth rate, λs. We use λs to construct fitness landscapes and show how different forms of stochasticity influence its topography. We prove the existence of a unique stochastic growth rate, λs, which is independent of the initial population vector, and show that Tuljapurkar's perturbation analysis for log(λs) can be used to calculate elasticities

    Foundering on the Shores of Curriculum: The Risks and Rewards of Interdisciplinarity

    Get PDF
    Editorial Introduction for Volume 8 Number 1 (2010)
    corecore