A5028315092- Evolution and Genetic Dynamics
- Physiological and biochemical adaptations
- Plant and animal studies
- Animal Ecology and Behavior Studies
- Ecology and Vegetation Dynamics Studies
- Evolutionary Game Theory and Cooperation
- Ecosystem dynamics and resilience
- Species Distribution and Climate Change
- Animal Behavior and Reproduction
- Isotope Analysis in Ecology
- Mathematical and Theoretical Epidemiology and Ecology Models
- Advanced Thermodynamics and Statistical Mechanics
- Marine and coastal ecosystems
- Fish Ecology and Management Studies
- Yersinia bacterium, plague, ectoparasites research
- Wildlife Ecology and Conservation
- Aquatic Ecosystems and Phytoplankton Dynamics
- Insect and Arachnid Ecology and Behavior
- Sustainability and Ecological Systems Analysis
- Complex Systems and Time Series Analysis
- Complex Systems and Decision Making
- Zoonotic diseases and public health
- Marine and fisheries research
- Forecasting Techniques and Applications
- Consumer Market Behavior and Pricing
Yale University
2016-2025
ORCID
2021
Lund University
2018-2019
University of California, Santa Cruz
2015
University of Potsdam
2010
University of Calgary
2007-2008
McGill University
2005-2007
University of Guelph
2004-2005
Increases in the frequency, severity and duration of temperature extremes are anticipated near future. Although recent work suggests that changes variation will have disproportionately greater effects on species than to mean, much climate change research ecology has focused impacts mean change. Here, we couple fine-grained projections (2050-2059) thermal performance data from 38 ectothermic invertebrate contrast with those a simple model. We show based alone differ substantially...
Biological populations are strongly influenced by the random variation in their environment. The spectrum of frequencies noise is particularly important to dynamics and persistence. Here we present an analysis variance spectra a wide variety long-term time series environmental variables. Spectra were well approximated inverse power law 1/fβ within appropriate range f; however, majority “flattened” at low frequencies. With some qualification found spectral exponents (β) corroborate earlier...
Paramount to our ability manage and protect biological communities from impending changes in the environment is an understanding of how will respond. General mathematical models community dynamics are often too simplistic accurately describe this response, partly retain tractability for lack biologically pleasing functions representing model/environment interface. We address these problems plausibility community/environment by incorporating Boltzmann factor (temperature dependence) a...
Changing temperature can substantially shift ecological communities by altering the strength and stability of trophic interactions. Because many rates are constrained temperature, new approaches required to understand how simultaneous changes in multiple alter relative performance species their We develop an energetic approach identify relationship between biomass fluxes standing across levels. Our links dynamics measure temperature-dependent interactions determine these food web stability....
Interference competition occurs when access to resources is negatively affected by the presence of other individuals. Within a species or population, this known as mutual interference, and it often modelled with scaling exponent, m, on number predators. Originally, interference was thought vary along continuum from prey dependence (no interference; m = 0) ratio (m -1), but debate in 1990's early 2000's focused whether better simplification. Some have argued more recently that likely be...
Trophic cascades are indirect positive effects of predators on resources via control intermediate consumers. Larger-bodied appear to induce stronger trophic (a greater rebound resource density toward carrying capacity), but how this happens is unknown because we lack a clear depiction the strength determined. Using consumer models, first show that cascade has an upper limit set by interaction between basal group and its approached as predator increases. We then express explicitly in terms...
Recent studies suggest that selection can allow coexistence in situations where ecological dynamics lead to competitive exclusion, provided there is a trade-off between traits optimal for interacting with conspecifics and heterospecifics. Despite compelling empirical evidence, no general framework elucidating how when will natural communities. Here we develop such mechanism term "neighbor-dependent selection." We show this both augment conditions niche partitioning enable exclusion. The...
Community biomass is often less variable than the biomasses of populations within community, yet attempts to implicate compensatory dynamics between as a cause this relationship fail. In part, may be due lack appropriate metrics for variability, but there also great potential large-scale processes such seasonality or longer-term environmental change obscure important at other temporal scales. study, we apply scale-resolving method long-term plankton data, identify specific scales which...
Resource competition is thought to drive divergence in resource use traits (character displacement) by generating selection favoring individuals able resources unavailable others. However, this picture assumes nutritionally substitutable (e.g., different prey species). When species compete for essential nutrients), theory predicts that drives character convergence. We used models of two competing address several issues not considered existing theory. The incorporated either slow evolutionary...
Laboratory measurements of physiological and demographic tolerances are important in understanding the impact climate change on species diversity; however, it has been recognized that forecasts based solely these laboratory estimates overestimate risk by omitting capacity for to utilize microclimatic variation via behavioral adjustments activity patterns or habitat choice. The complex, often context-dependent nature, microclimate utilization an impediment advancement general predictive...
Summary Body size is of fundamental importance to the structure and function natural systems, yet factors selecting for certain body sizes are still not well understood. Resource supply levels clearly play a role in setting size, but current theory, optimality functions tied population dynamics that govern resource supply, minimizing our ability understand how evolves response ecological context. We integrated supply‐demand ( SD ) model evolution with predator–prey create dynamic describes...
Global change is rapidly and fundamentally altering many of the processes regulating flux energy throughout ecosystems, although researchers now understand effect temperature on key rates (such as aquatic primary productivity), theoretical foundation needed to generate forecasts biomass dynamics extinction risk remains underdeveloped. We develop new theory that describes interconnected effects nutrients phytoplankton populations show thermal response equilibrium (i.e. carrying capacity)...
Abstract Natural food webs are species‐rich, but classical theory suggests that they should be unstable and extinction‐prone. Asynchronous fluctuations in the densities of competing consumers can stabilize web dynamics constant environments. However, environmental often synchronize nature. Using same ‘diamond‐shape’ model first used to demonstrate stabilizing effects asynchrony environments, we show weak‐to‐moderate environmentally induced consumer mortality rates while disrupting...
Population abundance is negatively related to body size for many types of organisms. Despite the ubiquity size-density scaling relationships, we lack a general understanding underlying mechanisms. Although dynamic models suggest that it possible predict intercept and slope relationship from prior observations, this has never been empirically attempted. Here fully parameterize set consumer-resource mammalian carnivores successfully group without use free parameters. All produced similar...
The potential connection between exploitation and interference competition was recognized long ago but has not been evaluated. We measured the levels of both forms for protist Didinium preying upon Paramecium . Across populations, intensity tightly linked to intensity, form this relationship follows from a simple model interaction speeds. variation in as large across populations observed previously species variety taxa including birds, mammals, insects, crustaceans, flatworms protists. link...
Summary Although mass and temperature are strong predictors of metabolic rates, there is considerable unexplained variation in rates both within across species after body size taken into account. Some this may be due to changes the rate food intake with population density, as metabolism depends on throughput fuel biochemical reactions. Using data collected from literature, we show that individual negatively correlated density for a wide range organisms including primary producers consumers....
Summary Recent work indicates that the interaction between body‐size‐dependent demographic processes can generate macroecological patterns such as scaling of population density with body size. In this study, we evaluate possibility for grazing protists and also test whether parameters in these models are correlated after controlling We compiled data on body‐size dependence consumer–resource interactions heterotrophic algae laboratory studies. then used nested dynamic to predict both height...
Although competing species are expected to exhibit compensatory dynamics (negative temporal covariation), empirical work has demonstrated that competitive communities often synchronous (positive covariation). This led the suggestion environmental forcing dominates dynamics; however, and may appear at different length scales and/or times, making it challenging identify their relative importance. We compiled 58 long-term datasets of zooplankton abundance in north-temperate sub-tropical lakes...
Abstract Species can adjust their traits in response to selection which may strongly influence species coexistence. Nevertheless, current theory mainly assumes distinct and time‐invariant trait values. We examined the combined effects of range speed adaptation on coexistence using an innovative multispecies predator–prey model. It allows for temporal changes all predator prey thus simultaneous coadaptation within among trophic levels. show that very small or slow did not facilitate because...
Environmental variability is ubiquitous, but its effects on populations are not fully understood or predictable. Recent attention has focused how rapid evolution can impact ecological dynamics via adaptive trait change. However, the of change arising from plastic responses received less attention, and often assumed to optimize performance unfold a separate, faster timescale than dynamics. Challenging these assumptions, we propose that gradual plasticity important for dynamics, present study...
Metacommunity theory and its constituent of island biogeography (TIB) have the potential to unify ecology across different scales. The TIB has been successful in predicting alpha diversity patterns, such as species-area relationships species-abundance distributions, but lags behind spatial beta patterns. In this study we use starting point integrate patterns into metacommunity theory. We first derive theoretical predictions for expected under classic MacArthur Wilson framework, where all...