Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 8 of 8
Full-Text Articles in Life Sciences
Creative Citizen Science Illuminates Complex Ecological Responses To Climate Change, Abraham J. Miller-Rushing, Amanda S. Gallinat, Richard B. Primack
Creative Citizen Science Illuminates Complex Ecological Responses To Climate Change, Abraham J. Miller-Rushing, Amanda S. Gallinat, Richard B. Primack
Biology Faculty Publications
Climate change is causing the timing of key behaviors (i.e., phenology) to shift differently across trophic levels and among some interacting organisms (e.g., plants and pollinators, predators and prey), suggesting that interactions among species are being disrupted (1, 2). Studying the phenology of interactions, however, is difficult, which has limited researchers’ ability to zero in on changes in specific interactions or on the consequences of mismatches. In PNAS, Hassall et al. (3) use a combination of citizen science techniques to investigate the effects of climate change on dozens of specific interactions. They focus on a Batesian mimicry complex involving stinging …
Strong Self-Limitation Promotes The Persistence Ofrare Species, G. M. Yenni, P. B. Adler, S.K. Morgan Ernest
Strong Self-Limitation Promotes The Persistence Ofrare Species, G. M. Yenni, P. B. Adler, S.K. Morgan Ernest
Biology Faculty Publications
Theory has recognized a combination of niche and neutral processes each contributing, with varying importance, to species coexistence. However, long-term persistence of rare species has been difficult to produce in trait-based models of coexistence that incorporate stochastic dynamics, raising questions about how rare species persist despite such variability. Following recent evidence that rare species may experience significantly different population dynamics than dominant species, we use a plant community model to simulate the effect of disproportionately strong negative frequency dependence on the long-term persistence of the rare species in a simulated community. This strong self-limitation produces long persistence times for the …
Species Compositionand Abundance Of Mammalian Communities, K. M. Thibault, S. R. Supp, M. Griffin, Ethan P. White, S.K. Morgan Ernest
Species Compositionand Abundance Of Mammalian Communities, K. M. Thibault, S. R. Supp, M. Griffin, Ethan P. White, S.K. Morgan Ernest
Biology Faculty Publications
Ecologists have long sought to understand the mechanisms underlying the assembly and structure of communities. Such understanding is relevant to both basic science and conservation-related issues. The macroecological approach to this problem involves asking scientific questions using a large number of communities in order to elucidate generalities in pattern and process. Such analyses are typically conducted using a substantial amount of data from a particular taxonomic group across a diversity of systems. Large community databases are available for a number of taxa, but no publicly available database exists for mammals. Given the logistical challenges of collecting such data de novo, …
On The Use Of Log-Transformation Vs. Nonlinear Regression For Analyzing Biological Power-Laws, Xiao Xiao, Ethan P. White, M. B. Hooten, Susan L. Durham
On The Use Of Log-Transformation Vs. Nonlinear Regression For Analyzing Biological Power-Laws, Xiao Xiao, Ethan P. White, M. B. Hooten, Susan L. Durham
Biology Faculty Publications
Power-law relationships are among the most well-studied functional relationships in biology. Recently the common practice of fitting power-laws using linear regression on log-transformed data (LR) has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations we demonstrate that the error distribution determines which method performs better, with LR better characterizing data with multiplicative lognormal error and NLR better characterizing data with additive, homoscedastic, normal error. Analysis of 471 biological power-laws shows that both …
On Estimating The Exponent Of Power-Law Frequency Distributions, Ethan P. White, B. J. Enquist, J. L. Green
On Estimating The Exponent Of Power-Law Frequency Distributions, Ethan P. White, B. J. Enquist, J. L. Green
Biology Faculty Publications
Power-law frequency distributions characterize a wide array of natural phenomena. In ecology, biology, and many physical and social sciences, the exponents of these power-laws are estimated to draw inference about the processes underlying the phenomenon, to test theoretical models, and to scale up from local observations to global patterns. Therefore, it is essential that these exponents be estimated accurately. Unfortunately, the binning-based methods traditionally utilized in ecology and other disciplines perform quite poorly. Here we discuss more sophisticated methods for fitting these exponents based on cumulative distribution functions and maximum likelihood estimation. We illustrate their superior performance at estimating known …
Two-Phase Species-Time Relationships In North American Land Birds, Ethan P. White
Two-Phase Species-Time Relationships In North American Land Birds, Ethan P. White
Biology Faculty Publications
The species-time relationship (STR) is a macroecological pattern describing the increase in the observed species richness with the length of time censused. Understanding STRs is important for understanding the ecological processes underlying temporal turnover and species richness. However, accurate characterization of the STR has been hampered by the influence of sampling. I analyzed species-time relationships for 521 breeding bird survey communities. I used a model of sampling effects to demonstrate that the increase in richness was not due exclusively to sampling. I estimated the time scale at which ecological processes became dominant over sampling effects using a two-phase model combining …
A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker
A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker
Biology Faculty Publications
No abstract provided.
Individualistic Perspectives On Plant Competition, Nancy J. Huntly
Individualistic Perspectives On Plant Competition, Nancy J. Huntly
Biology Faculty Publications
No abstract provided.