@article{adler_michaud_ellner_mcart_stevenson_irwin_2018, title={Disease where you dine: plant species and floral traits associated with pathogen transmission in bumble bees}, volume={99}, ISSN={0012-9658 1939-9170}, url={http://dx.doi.org/10.1002/ecy.2503}, DOI={10.1002/ecy.2503}, abstractNote={Hotspots of disease transmission can strongly influence pathogen spread. Bee pathogens may be transmitted via shared floral use, but the role of plant species and floral trait variation in shaping transmission dynamics is almost entirely unexplored. Given the importance of pathogens for the decline of several bee species, understanding whether and how plant species and floral traits affect transmission could give us important tools for predicting which plant species may be hotspots for disease spread. We assessed variation in transmission via susceptibility (probability of infection) and mean intensity (cell count of infected bees) of the trypanosomatid gut pathogen Crithidia bombi to uninfected Bombus impatiens workers foraging on 14 plant species, and assessed the role of floral traits, bee size and foraging behavior on transmission. We also conducted a manipulative experiment to determine how the number of open flowers affected transmission on three plant species, Penstemon digitalis, Monarda didyma, and Lythrum salicaria. Plant species differed fourfold in the overall mean abundance of Crithidia in foraging bumble bees (mean including infected and uninfected bees). Across plant species, bee susceptibility and mean intensity increased with the number of reproductive structures per inflorescence (buds, flowers and fruits); smaller bees and those that foraged longer were also more susceptible. Trait-based models were as good or better than species-based models at predicting susceptibility and mean intensity based on AIC values. Surprisingly, floral size and morphology did not significantly predict transmission across species. In the manipulative experiment, more open flowers increased mean pathogen abundance fourfold in Monarda, but had no effect in the other two plant species. Our results suggest that variation among plant species, through their influence on pathogen transmission, may shape bee disease dynamics. Given widespread investment in pollinator-friendly plantings to support pollinators, understanding how plant species affect disease transmission is important for recommending plant species that optimize pollinator health.}, number={11}, journal={Ecology}, publisher={Wiley}, author={Adler, Lynn S. and Michaud, Kristen M. and Ellner, Stephen P. and McArt, Scott H. and Stevenson, Philip C. and Irwin, Rebecca E.}, year={2018}, month={Oct}, pages={2535–2545} }
 @article{schliekelman_ellner_gould_2005, title={Pest control by genetic manipulation of sex ratio}, volume={98}, DOI={10.1093/jee/98.1.18}, abstractNote={We model the release of insects carrying an allele at multiple loci that shifts sex ratios in favor of males. We model two approaches to sex ratio alteration. In the first (denoted SD), meiotic segregation (or sperm fertility) is distorted in favor of gametes carrying the male-determining genetic element (e.g., Y-chromosome). It is assumed that any male carrying at least one copy of the SD allele produces only genotypically male offspring. In the second approach (denoted PM), the inserted allele alters sex ratio by causing genetically female individuals to become phenotypically male. It is assumed that any insect carrying at least one copy of the PM allele is phenotypically male. Both approaches reduce future population growth by reducing the number of phenotypic females. The models allow variation in the number of loci used in the release, the size of the release, and the negative fitness effect caused by insertion of each sex ratio altering allele. We show that such releases may be at least 2 orders of magnitude more effective than sterile male releases (SIT) in terms of numbers of surviving insects. For example, a single SD release with two released insects for every wild insect and a 5% fitness cost per inserted allele could reduce the target population to 1/1000th of the no-release population size, whereas a similar-sized SIT release would only reduce the population to one-fifth of its original size. We also compare these two sex ratio alteration approaches to a female-killing (FK) system and the sterile male technique when there are repeated releases over a number of generations. In these comparisons, the SD approach is the most efficient with equivalent pest suppression achieved by release of ≈1 SD, 1.5–20 PM, 2–70 FK, and 16–3,000 SIT insects, depending on conditions. We also calculate the optimal number of SD and PM allele insertions to be used under various conditions, assuming that there is an additional genetic load incurred for each allelic insertion.}, number={1}, journal={Journal of Economic Entomology}, author={Schliekelman, P. and Ellner, S. and Gould, Fred}, year={2005}, pages={18–34} }
 @article{thomson_ellner_2003, title={Pair-edge approximation for heterogeneous lattice population models}, volume={64}, ISSN={["1096-0325"]}, DOI={10.1016/S0040-5809(03)00088-1}, abstractNote={To increase the analytical tractability of lattice stochastic spatial population models, several approximations have been developed. The pair-edge approximation is a moment-closure method that is effective in predicting persistence criteria and invasion speeds on a homogeneous lattice. Here we evaluate the effectiveness of the pair-edge approximation on a spatially heterogeneous lattice in which some sites are unoccupiable, or "dead". This model has several possible interpretations, including a spatial SIS epidemic model, in which some sites are occupied by immobile host-species individuals while others are empty. We find that, as in the homogeneous model, the pair-edge approximation is significantly more accurate than the ordinary pair approximation in determining conditions for persistence. However, habitat heterogeneity decreases invasion speed more than is predicted by the pair-edge approximation, and the discrepancy increases with greater clustering of "dead" sites. The accuracy of the approximation validates the underlying heuristic picture of population spread and therefore provides qualitative insight into the dynamics of lattice models. Conversely, the situations where the approximation is less accurate reveals limitations of pair approximation in the presence of spatial heterogeneity.}, number={3}, journal={THEORETICAL POPULATION BIOLOGY}, author={Thomson, NA and Ellner, SP}, year={2003}, month={Nov}, pages={271–280} }
 @article{ellner_seifu_smith_2002, title={Fitting population dynamic models to time-series data by gradient matching}, volume={83}, number={8}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Ellner, S. P. and Seifu, Y. and Smith, R. H.}, year={2002}, pages={2256–2270} }
 @article{ellner_fieberg_ludwig_wilcox_2002, title={Precision of population viability analysis}, volume={16}, ISSN={["1523-1739"]}, DOI={10.1046/j.1523-1739.2002.00553.x}, abstractNote={Although population viability analysis (PVA) is widely used in setting conservation policy, there is disagreement about the usefulness of this method. Objections have been raised concerning the precision of predictions in view of the short time series of data available and the sensitivity of estimates of extinction risk to estimated parameters (Hamilton & Moller 1995; Taylor 1995; Groom & Pascual 1998; Ludwig 1999). Beissinger and Westphal (1998) reviewed the use of demographic models for endangered-species management. They pointed out that poor data cause difficulties in parameter estimation, which in turn lead to unreliable estimates of extinction risk. There are additional}, number={1}, journal={CONSERVATION BIOLOGY}, author={Ellner, SP and Fieberg, J and Ludwig, D and Wilcox, C}, year={2002}, month={Feb}, pages={258–261} }
 @article{morales_ellner_2002, title={Scaling up animal movements in heterogeneous landscapes: The importance of behavior}, volume={83}, number={8}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Morales, J. M. and Ellner, S. P.}, year={2002}, pages={2240–2247} }
 @article{shertzer_ellner_2002, title={State-dependent energy allocation in variable environments: Life history evolution of a rotifer}, volume={83}, number={8}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Shertzer, K. W. and Ellner, S. P.}, year={2002}, pages={2181–2193} }
 @article{schliekelman_ellner_2001, title={Egg size evolution and energetic constraints on population dynamics}, volume={60}, ISSN={["1096-0325"]}, DOI={10.1006/tpbi.2001.1524}, abstractNote={We use population models that are based on dynamic energy budget models for individuals in order to study the evolution of offspring size and its relationship to the evolution of population dynamics. We show the existence of alternative evolutionarily stable strategies for offspring investment strategy resulting from a trade off between offspring number and time-to-maturity. The model predicts egg energy in Daphnia magna well, and suggests that the observed egg energy in D. magna is the result of selection for minimal egg investment constrained by minimum viable egg energy, combined with selection for a juvenile energy reserve. The selection for minimal egg size pushes populations toward chaotic dynamics. However, the minimum viable egg size combined with low efficiency of conversion of energy to new biomass is sufficient to keep population dynamics out of chaos.}, number={2}, journal={THEORETICAL POPULATION BIOLOGY}, author={Schliekelman, P and Ellner, SP}, year={2001}, month={Sep}, pages={73–92} }
 @misc{fieberg_ellner_2001, title={Stochastic matrix models for conservation and management: a comparative review of methods}, volume={4}, ISSN={["1461-0248"]}, DOI={10.1046/j.1461-0248.2001.00202.x}, abstractNote={Stochastic matrix models are frequently used by conservation biologists to measure the viability of species and to explore various management actions. Models are typically parameterized using two or more sets of estimated transition rates between age/size/stage classes. While standard methods exist for analyzing a single set of transition rates, a variety of methods have been employed to analyze multiple sets of transition rates. We review applications of stochastic matrix models to problems in conservation and use simulation studies to compare the performance of different analytic methods currently in use. We find that model conclusions are likely to be robust to the choice of parametric distribution used to model vital rate fluctuations over time. However, conclusions can be highly sensitive to the within-year correlation structure among vital rates, and therefore we suggest using analytical methods that provide a means of conducting a sensitivity analysis with respect to correlation parameters. Our simulation results also suggest that the precision of population viability estimates can be improved by using matrix models that incorporate environmental covariates in conjunction with experiments to estimate transition rates under a range of environmental conditions.}, number={3}, journal={ECOLOGY LETTERS}, author={Fieberg, J and Ellner, SP}, year={2001}, month={May}, pages={244–266} }
 @article{fussmann_ellner_shertzer_hairston_2000, title={Crossing the Hopf bifurcation in a live predator-prey system}, volume={290}, number={5495}, journal={Science}, author={Fussmann, G. F. and Ellner, S. P. and Shertzer, K. W. and Hairston, N. G.}, year={2000}, pages={1358–1360} }
 @article{easterling_ellner_2000, title={Dormancy strategies in a random environment: Comparing structured and unstructured models}, volume={2}, number={4}, journal={Evolutionary Ecology Research}, author={Easterling, M. R. and Ellner, S. P.}, year={2000}, pages={387–407} }
 @article{mccauley_kendall_janssen_wood_murdoch_hosseini_briggs_ellner_nisbet_sabelis_et al._2000, title={Inferring colonization processes from population dynamics inspatially structured predator-prey systems}, volume={81}, number={12}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={McCauley, E. and Kendall, B. E. and Janssen, A. and Wood, S. and Murdoch, W. W. and Hosseini, P. and Briggs, C. J. and Ellner, S. P. and Nisbet, R. M. and Sabelis, M. W. and et al.}, year={2000}, pages={3350–3361} }
 @article{pascual_ellner_2000, title={Linking ecological patterns to environmental forcing via nonlinear time series models}, volume={81}, number={10}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Pascual, M. and Ellner, S. P.}, year={2000}, pages={2767–2780} }
 @article{turchin_ellner_2000, title={Living on the edge of chaos: Population dynamics of Fennoscandian voles}, volume={81}, number={11}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Turchin, P. and Ellner, S. P.}, year={2000}, pages={3099–3116} }
 @article{easterling_ellner_dixon_2000, title={Size-specific sensitivity: Applying a new structured population model}, volume={81}, number={3}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Easterling, M. R. and Ellner, S. P. and Dixon, P. M.}, year={2000}, pages={694–708} }
 @article{jost_ellner_2000, title={Testing for predator dependence in predator-prey dynamics: a non-parametric approach}, volume={267}, DOI={10.1098/rspb.2000.1186}, abstractNote={The functional response is a key element in all predator-prey interactions. Although functional responses are traditionally modelled as being a function of prey density only, evidence is accumulating that predator density also has an important effect. However, much of the evidence comes from artificial experimental arenas under conditions not necessarily representative of the natural system, and neglecting the temporal dynamics of the organism (in particular the effects of prey depletion on the estimated functional response). Here we present a method that removes these limitations by reconstructing the functional response non-parametrically from predator-prey time-series data. This method is applied to data on a protozoan predator-prey interaction, and we obtain significant evidence of predator dependence in the functional response. A crucial element in this analysis is to include time-lags in the prey and predator reproduction rates, and we show that these delays improve the fit of the model significantly. Finally, we compare the non-parametrically reconstructed functional response to parametric forms, and suggest that a modified version of the Hassell V arley predator interference model provides a simple and flexible function for theoretical investigation and applied modelling.}, number={1453}, journal={Proceedings of the Royal Society of London. Series B. Biological Sciences}, author={Jost, C. and Ellner, S. P.}, year={2000}, pages={1611–1620} }
 @article{peck_ellner_gould_2000, title={Varying migration and deme size and the feasibility of the shifting balance}, volume={54}, ISSN={["0014-3820"]}, DOI={10.1111/j.0014-3820.2000.tb00035.x}, abstractNote={EvolutionVolume 54, Issue 1 p. 324-327 Free Access VARYING MIGRATION AND DEME SIZE AND THE FEASIBILITY OF THE SHIFTING BALANCE Steven L. Peck, Steven L. Peck USDA/ARS, Tropical Fruit and Vegetable Research Laboratory, P.O. Box 4459, Hilo, Hawaii 96720 E-mail: sp@aloha.net Present address: Zoology Department, Brigham Young University, Provo, Utah 84602–5255; E-mail: steven_peck@byu.edu.Search for more papers by this authorStephen P. Ellner, Stephen P. Ellner Biomathematics Graduate Program, Department of Statistics, North Carolina State University, Raleigh, North Carolina 27695–8203 E-mail: ellner@stat.ncsu.eduSearch for more papers by this authorFred Gould, Fred Gould Department of Entomology, North Carolina State University, Raleigh, North Carolina 27695–7634 E-mail: fgould@unity.ncsu.eduSearch for more papers by this author Steven L. Peck, Steven L. Peck USDA/ARS, Tropical Fruit and Vegetable Research Laboratory, P.O. Box 4459, Hilo, Hawaii 96720 E-mail: sp@aloha.net Present address: Zoology Department, Brigham Young University, Provo, Utah 84602–5255; E-mail: steven_peck@byu.edu.Search for more papers by this authorStephen P. Ellner, Stephen P. Ellner Biomathematics Graduate Program, Department of Statistics, North Carolina State University, Raleigh, North Carolina 27695–8203 E-mail: ellner@stat.ncsu.eduSearch for more papers by this authorFred Gould, Fred Gould Department of Entomology, North Carolina State University, Raleigh, North Carolina 27695–7634 E-mail: fgould@unity.ncsu.eduSearch for more papers by this author First published: 09 May 2007 https://doi.org/10.1111/j.0014-3820.2000.tb00035.xCitations: 17 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume54, Issue1February 2000Pages 324-327 ReferencesRelatedInformation}, number={1}, journal={EVOLUTION}, author={Peck, SL and Ellner, SP and Gould, F}, year={2000}, month={Feb}, pages={324–327} }
 @article{fieberg_ellner_2000, title={When is it meaningful to estimate an extinction probability?}, volume={81}, number={7}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Fieberg, J. and Ellner, S. P.}, year={2000}, pages={2040–2047} }
 @article{peck_gould_ellner_1999, title={Spread of resistance in spatially extended regions of transgenic cotton: Implications for management of Heliothis virescens (Lepidoptera: Noctuidae)}, volume={92}, DOI={10.1093/jee/92.1.1}, abstractNote={Through the use of a stochastic, spatially explicit, simulation model, we explored factors that may influence the regional development of resistance in Heliothis virescens (F.) to a Bacillus thuringiensis (Bt) δ-endotoxin in transgenic cotton. The model represents the age structure of adults and larvae, plant to plant movement of larvae within a field, migration of adults among fields, plant type-genotype specific selection, and development time. We find that the spatial scale and the temporal pattern of refuges can have a strong effect on the development of resistance to B. thuringiensis in transgenic cotton. The time to resistance was in general significantly longer in regions where the same fields were used as a refuge year after year, compared with regions where the refuge fields are changed randomly from year to year. Spring movement of emerging adults onto wild hosts delays resistance if the movement is far enough from the field in which pupae overwintered. Increases in the summer migration rate and the distance moved delayed resistance development up to a point at which higher rates do not further delay resistance. Refuges were an effective strategy for delaying resistance. We found that delays in larval development time on Bt cotton may either increase or decrease the rate of resistance development, depending on complex interactions with the length of the growing season. Larval movement between Bt and non-Bt plants was found to increase the rate at which resistance developed, but this may be ameliorated with increasing mortality costs associated with larval movement.}, number={1}, journal={Journal of Economic Entomology}, author={Peck, S. L. and Gould, Fred and Ellner, S. P.}, year={1999}, pages={1–16} }
 @article{ellner_hairston_kearns_babai_1999, title={The roles of fluctuating selection and long-term diapause in microevolution of diapause timing in a freshwater copepod}, volume={53}, ISSN={["1558-5646"]}, DOI={10.2307/2640924}, number={1}, journal={EVOLUTION}, author={Ellner, SP and Hairston, NG and Kearns, CM and Babai, D}, year={1999}, month={Feb}, pages={111–122} }
 @article{kendall_briggs_murdoch_turchin_ellner_mccauley_nisbet_wood_1999, title={Why do populations cycle? A synthesis of statistical and mechanistic modeling approaches}, volume={80}, number={6}, journal={Ecology (Brooklyn, New York, N.Y.)}, author={Kendall, B. E. and Briggs, C. J. and Murdoch, W. W. and Turchin, P. and Ellner, S. P. and McCauley, E. and Nisbet, R. M. and Wood, S. N.}, year={1999}, pages={1789–1805} }
 @article{peck_ellner_gould_1998, title={A spatially explicit stochastic model demonstrates the feasibility of Wright's Shifting Balance Theory}, volume={52}, ISSN={["1558-5646"]}, DOI={10.2307/2411353}, number={6}, journal={EVOLUTION}, author={Peck, SL and Ellner, SP and Gould, F}, year={1998}, month={Dec}, pages={1834–1839} }
 @inproceedings{ellner_hairston_babai_1998, title={Long-term diapause and spreading of risk across the life cycle}, booktitle={Evolutionary and ecological aspects of crustacean diapause: Proceedings of the symposium 'Diapause in the Crustacea--with invited contributions on non-crustacean taxa' held in Gent, August 24-29, 1997 (Ergebnisse der Limnologie=Advances in limnology series; Heft. 52)}, publisher={Stuttgart: E. Schweizerbart'sche Verlagsbuchhandlung}, author={Ellner, S. P. and Hairston, N. G., Jr. and Babai, D.}, editor={L. Brendonck, L. de Meester and Hairston, N., Jr.Editors}, year={1998}, pages={297–312} }
 @article{ellner_bailey_bobashev_gallant_grenfell_nychka_1998, title={Noise and nonlinearity in measles epidemics: Combining mechanistic and statistical approaches to population modeling}, volume={151}, ISSN={["1537-5323"]}, DOI={10.1086/286130}, abstractNote={We present and evaluate an approach to analyzing population dynamics data using semimechanistic models. These models incorporate reliable information on population structure and underlying dynamic mechanisms but use nonparametric surface‐fitting methods to avoid unsupported assumptions about the precise form of rate equations. Using historical data on measles epidemics as a case study, we show how this approach can lead to better forecasts, better characterizations of the dynamics, and a better understanding of the factors causing complex population dynamics relative to either mechanistic models or purely descriptive statistical time‐series models. The semimechanistic models are found to have better forecasting accuracy than either of the model types used in previous analyses when tested on data not used to fit the models. The dynamics are characterized as being both nonlinear and noisy, and the global dynamics are clustered very tightly near the border of stability (dominant Lyapunov exponent λ ≈ 0). However, locally in state space the dynamics oscillate between strong short‐term stability and strong short‐term chaos (i.e., between negative and positive local Lyapunov exponents). There is statistically significant evidence for short‐term chaos in all data sets examined. Thus the nonlinearity in these systems is characterized by the variance over state space in local measures of chaos versus stability rather than a single summary measure of the overall dynamics as either chaotic or nonchaotic.}, number={5}, journal={AMERICAN NATURALIST}, author={Ellner, SP and Bailey, BA and Bobashev, GV and Gallant, AR and Grenfell, BT and Nychka, DW}, year={1998}, month={May}, pages={425–440} }
 @article{ellner_sasaki_haraguchi_matsuda_1998, title={Speed of invasion in lattice population models: pair-edge approximation}, volume={36}, ISSN={["0303-6812"]}, DOI={10.1007/s002850050109}, number={5}, journal={JOURNAL OF MATHEMATICAL BIOLOGY}, author={Ellner, SP and Sasaki, A and Haraguchi, Y and Matsuda, H}, year={1998}, month={Apr}, pages={469–484} }
 @article{ellner_kendall_wood_mccauley_briggs_1997, title={Inferring mechanism from time-series data: Delay-differential equations}, volume={110}, number={3-4}, journal={Physica. D, Nonlinear Phenomena}, author={Ellner, S. P. and Kendall, B. E. and Wood, S. N. and McCauley, E. and Briggs, C. J.}, year={1997}, pages={182–194} }
 @article{peck_ellner_1997, title={The effect of economic thresholds and life-history parameters on the evolution of pesticide resistance in a regional setting}, volume={149}, ISSN={["0003-0147"]}, DOI={10.1086/285978}, abstractNote={We explore the dynamics of alleles conferring insecticide resistance in agroecosystems in which economic thresholds are used to manage insect pest populations. The dynamics of economic thresholds on resistance evolution are first explored in a single-field model. A two-dimensional cellular automata model is then used to examine the effects of migration, refuges, and crop rotation in a large region of fields under different management strategies. The single-field model indicates that economic thresholds may have important implications for pesticide management strategies, because resistance evolution is no longer independent of the growth process. In the regional model, the growth rate of the population, the selection pressure on the resistant allele, and migration all affect the time to resistance. Rotation is most beneficial when migration rates are either very high or very low and has little effect at intermediate migration rates. Resistance develops in large patches, so the level of resistance in a given field may be only weakly related to the history of pesticide treatment in that field. This finding may explain the high regional variability found in field studies of resistance in pests such as Colorado potato beetle.}, number={1}, journal={AMERICAN NATURALIST}, author={Peck, SL and Ellner, SP}, year={1997}, month={Jan}, pages={43–63} }
 @inbook{ellner_1997, title={You bet your life: Life-history strategies in fluctuating environments (1)}, booktitle={Case studies in mathematical modeling: Ecology, physiology, and cell biology}, publisher={Upper Saddle River, N.J.: Prentice Hall}, author={Ellner, S. P.}, year={1997}, pages={3–24} }
 @article{ellner_1996, title={Environmental fluctuations and the maintenance of genetic diversity in age or stage-structured populations}, volume={58}, ISSN={["1522-9602"]}, DOI={10.1007/BF02458284}, number={1}, journal={BULLETIN OF MATHEMATICAL BIOLOGY}, author={Ellner, S}, year={1996}, month={Jan}, pages={103–127} }
 @article{ellner_sasaki_1996, title={Patterns of genetic polymorphism maintained by fluctuating selection with overlapping generations}, volume={50}, ISSN={["0040-5809"]}, DOI={10.1006/tpbi.1996.0022}, abstractNote={We study the form of polymorphisms that can be maintained by the joint effects of generation overlap and randomly fluctuating selection, acting on a quantitative trait affecting offspring viability. The genetic system can be single locus or multilocus, haploid or diploid. Selection is assumed to be stabilizing with a randomly fluctuating optimum, and we assume additive allelic effects without epistasis. For fluctuations above a certain threshold, nonzero genetic variance is maintained in an evolutionarily stable population. Our model allows a continuum of alleles with arbitrary effects at each locus. Nonetheless, the genotype distribution in an evolutionarily stable population is discrete--a polymorphism of a few alleles with distinctly different effects--and often involves only a pair of alleles at each locus. The form of the genotype distribution depends on the number of loci affecting the trait, and on the kurtosis of the distribution of the phenotypic optimum theta. If the trait is affected by several loci, the number of polymorphic loci increases with increased variance of fluctuations in selection. For distributions of theta with negative kurtosis (i.e., lower kurtosis than a Gaussian) the number of polymorphic loci increases gradually (0-->1-->2--> ...M), and the genetic variability is in the form of a few diallelic or triallelic loci with alleles of large effect. For distributions with positive kurtosis, the increase is abrupt (0 -> many) and involves many diallelic loci. These results do not fit the conventional multivariate Gaussian or near-Gaussian models for quantitative traits, but may partially explain recent findings that heritable variation in natural populations is often due to genes of large effect.}, number={1}, journal={THEORETICAL POPULATION BIOLOGY}, author={Ellner, S and Sasaki, A}, year={1996}, month={Aug}, pages={31–65} }
 @article{ellner_neori_krom_tsai_easterling_1996, title={Simulation model of recirculating mariculture with seaweed biofilter: Development and experimental tests of the model}, volume={143}, ISSN={["0044-8486"]}, DOI={10.1016/0044-8486(95)01241-9}, abstractNote={A simulation model was developed for an experimental recirculating mariculture system in Elat, Israel. The system cultures gilthead seabream (Sparus aurata), using a seaweed biofilter (Ulva lactuca) to maintain water quality, reduce the flow-through rate of seawater, and reduce the nutrient load in effluents. The model describes the production, transfer, transformations, and losses of inorganic N in the system, in a relatively simple compartment model framework. The model was able to match very closely the experimental data on which it is based. Moreover, the model was able to predict the system's behavior in two additional experiments, which provided independent tests of the model under nonstandard operating conditions (reduced food input and reduced water recirculation rate). The success of the model beyond the range of conditions used in its construction suggests that the model provides a valid mechanistic description of the essential processes affecting inorganic N in the system. Sensitivity analysis of the model indicates that levels of ammonia-N and oxidized N in the system were most strongly affected by the rates of ammonia-N excretion by the fish and ammonia-N uptake by the seaweed, followed by the water inflow and recirculation rates. Sensitivities to internal transformation rate parameters were lower, which might explain the relative seasonal constancy of the system. Simulation experiments indicate that the experimental system could support much higher stocking densities of fish without exceeding tolerable levels of ammonia-N.}, number={2}, journal={AQUACULTURE}, author={Ellner, S and Neori, A and Krom, MD and Tsai, K and Easterling, MR}, year={1996}, month={Jul}, pages={167–184} }
 @article{ellner_turchin_1995, title={Chaos in a noisy world - new methods and evidence from time-series analysis}, volume={145}, number={3}, journal={American Naturalist}, author={Ellner, S. and Turchin, P.}, year={1995}, pages={343–375} }
 @article{ellner_hairston_1994, title={ROLE OF OVERLAPPING GENERATIONS IN MAINTAINING GENETIC-VARIATION IN A FLUCTUATING ENVIRONMENT}, volume={143}, ISSN={["1537-5323"]}, DOI={10.1086/285610}, abstractNote={Population genetics theory suggests that temporally fluctuating selection on phenotypes can act to maintain genetic variance only under very restrictive conditions. However, this conclusion is based on models with discrete nonoverlapping generations. We propose here that temporally fluctuating selection can indeed contribute significantly to the maintenance of genetic variation when the effects of overlapping generations and age-specific or stage-specific selection are considered. We develop a simple model for a population with overlapping generations, experiencing stabilizing selection with a temporally fluctuating optimum, and subject to repeated invasions by mutants with alternative phenotypes. We find that an evolutionarily stable population must have positive genetic variance maintained by selection so long as the product (variance of fluctuations) times (amount of generation overlap) times (selection intensity) is sufficiently high. This result applies to haploid, diploid, single-locus, or multilocus inheritance, and it does not depend on any form of heterozygote advantage to maintain genetic variance. However, it depends on the map between genotype and phenotype being constrained. If a single genotype can produce an arbitrary distribution of phenotypes, then genetic variance is not maintained by selection.}, number={3}, journal={AMERICAN NATURALIST}, author={ELLNER, S and HAIRSTON, NG}, year={1994}, month={Mar}, pages={403–417} }