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Full-Text Articles in Life Sciences
How Fast Is Fast? Eco-Evolutionary Dynamics And Rates Of Change In Populations And Phenotypes, John Delong, Valery E. Forbes, Nika Galic, Jean P. Gibert, Robert G. Laport, Joseph S. Phillips, Janna M. Vavra
How Fast Is Fast? Eco-Evolutionary Dynamics And Rates Of Change In Populations And Phenotypes, John Delong, Valery E. Forbes, Nika Galic, Jean P. Gibert, Robert G. Laport, Joseph S. Phillips, Janna M. Vavra
School of Biological Sciences: Faculty Publications
It is increasingly recognized that evolution may occur in ecological time. It is not clear, however, how fast evolution – or phenotypic change more generally – may be in comparison with the associated ecology, or whether systems with fast ecological dynamics generally have relatively fast rates of phenotypic change. We developed a new dataset on standardized rates of change in population size and phenotypic traits for a wide range of species and taxonomic groups. We show that rates of change in phenotypes are generally no more than 2/3, and on average about 1/4, the concurrent rates of change in population …
Spatiotemporal Variation In Flow-Dependent Recruitment Of Long-Lived Riverine Fish: Model Development And Evaluation, Daisuke Goto, Martin J. Hamel, Jeremy J. Hammen, Mathew L. Rugg, Mark A. Pegg, Valery E. Forbes
Spatiotemporal Variation In Flow-Dependent Recruitment Of Long-Lived Riverine Fish: Model Development And Evaluation, Daisuke Goto, Martin J. Hamel, Jeremy J. Hammen, Mathew L. Rugg, Mark A. Pegg, Valery E. Forbes
School of Biological Sciences: Faculty Publications
Abstract Natural flow regimes can play a major role as an overarching ecosystem driver in reproduction and recruitment of riverine fishes. Human needs for freshwater however have altered hydrology of many riverine systems worldwide, threatening fish population sustainability. To understand and predict how spatiotemporal dynamics of flow regimes influence reproductive and recruitment variability, and ultimately population sustainability of shovelnose sturgeon (Scaphirhynchus platorynchus), we develop a spatially explicit (1D) individual-based population model that mechanistically (via energetics-based processes) simulates daily activities (dispersal, spawning, foraging, growth, and survival). With field observations of sturgeon and habitat conditions in a major tributary of …
Contributions Of Demography And Dispersal Parameters To The Spatial Spread Of A Stage-Structured Insect Invasion, Tom E. X. Miller, Brigitte Tenhumberg
Contributions Of Demography And Dispersal Parameters To The Spatial Spread Of A Stage-Structured Insect Invasion, Tom E. X. Miller, Brigitte Tenhumberg
School of Biological Sciences: Faculty Publications
Stage-structured models that integrate demography and dispersal can be used to identify points in the life cycle with large effects on rates of population spatial spread, information that is vital in the development of containment strategies for invasive species. Current challenges in the application of these tools include: (1) accounting for large uncertainty in model parameters, which may violate assumptions of ‘‘local’’ perturbation metrics such as sensitivities and elasticities, and (2) forecasting not only asymptotic rates of spatial spread, as is usually done, but also transient spatial dynamics in the early stages of invasion. We developed an invasion model for …
Impacts Of Insect Herbivory On Cactus Population Dynamics: Experimental Demography Across An Environmental Gradient, Tom E. X. Miller, Svata M. Louda, Karen A. Rose, James O. Eckberg
Impacts Of Insect Herbivory On Cactus Population Dynamics: Experimental Demography Across An Environmental Gradient, Tom E. X. Miller, Svata M. Louda, Karen A. Rose, James O. Eckberg
School of Biological Sciences: Faculty Publications
Understanding the role of consumers in plant population dynamics is important, both conceptually and practically. Yet, while the negative effects of herbivory on plant performance have been well documented, we know much less about how individuallevel damage translates to impacts on population growth or whether spatial variation in herbivory affects patterns of plant distribution. We studied the role of insect herbivory in the dynamics and distribution of the tree cholla cactus (Opuntia imbricata), a long-lived perennial plant, across an elevational gradient in central New Mexico, USA, from low-elevation grassland (1670 m) to a grassland–mountain transition zone (1720 m) …
Model Complexity Affects Transient Population Dynamics Following A Dispersal Event: A Case Study With Pea Aphids, Brigitte Tenhumberg, Andrew J. Tyre, Richard Rebarber
Model Complexity Affects Transient Population Dynamics Following A Dispersal Event: A Case Study With Pea Aphids, Brigitte Tenhumberg, Andrew J. Tyre, Richard Rebarber
School of Biological Sciences: Faculty Publications
Stage-structured population models predict transient population dynamics if the population deviates from the stable stage distribution. Ecologists’ interest in transient dynamics is growing because populations regularly deviate from the stable stage distribution, which can lead to transient dynamics that differ significantly from the stable stage dynamics. Because the structure of a population matrix (i.e., the number of life-history stages) can influence the predicted scale of the deviation, we explored the effect of matrix size on predicted transient dynamics and the resulting amplification of population size. First, we experimentally measured the transition rates between the different life-history stages and the adult …
Plant Reproductive Allocation Predicts Herbivore Dynamics Across Spatial And Temporal Scales, Tom E. X. Miller, Andrew J. Tyre, Svata M. Louda
Plant Reproductive Allocation Predicts Herbivore Dynamics Across Spatial And Temporal Scales, Tom E. X. Miller, Andrew J. Tyre, Svata M. Louda
School of Biological Sciences: Faculty Publications
Life-history theory suggests that iteroparous plants should be flexible in their allocation of resources toward growth and reproduction. Such plasticity could have consequences for herbivores that prefer or specialize on vegetative versus reproductive structures. To test this prediction, we studied the response of the cactus bug (Narnia pallidicornis) to meristem allocation by tree cholla cactus (Opuntia imbricata). We evaluated the explanatory power of demographic models that incorporated variation in cactus relative reproductive effort (RRE; the proportion of meristems allocated toward reproduction). Field data provided strong support for a single model that defined herbivore fecundity as a …