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Full-Text Articles in Climate
Geographic Differences In Effects Of Experimental Warming On Ant Species Diversity And Community Composition, S. L. Pelini, S. E. Diamond, L. M. Nichols, K. L. Stuble, A. M. Ellison, N. J. Sanders, R. R. Dunn, N. J. Gotelli
Geographic Differences In Effects Of Experimental Warming On Ant Species Diversity And Community Composition, S. L. Pelini, S. E. Diamond, L. M. Nichols, K. L. Stuble, A. M. Ellison, N. J. Sanders, R. R. Dunn, N. J. Gotelli
College of Arts and Sciences Faculty Publications
Ecological communities are being reshaped by climatic change. Losses and gains of species will alter community composition and diversity but these effects are likely to vary geographically and may be hard to predict from uncontrolled "natural experiments". In this study, we used open-top warming chambers to simulate a range of warming scenarios for ground-nesting ant communities at a northern (Harvard Forest, MA) and southern (Duke Forest, NC) study site in the eastern US. After 2.5 years of experimental warming, we found no significant effects of accumulated growing degree days or soil moisture on ant diversity or community composition at the …
Matrix Models For Quantifying Competitive Intransitivity From Species Abundance Data, Werner Ulrich, Santiago Soliveres, Wojciech Kryszewski, Fernando T. Maestre, Nicholas J. Gotelli
Matrix Models For Quantifying Competitive Intransitivity From Species Abundance Data, Werner Ulrich, Santiago Soliveres, Wojciech Kryszewski, Fernando T. Maestre, Nicholas J. Gotelli
College of Arts and Sciences Faculty Publications
In a network of competing species, a competitive intransitivity occurs when the ranking of competitive abilities does not follow a linear hierarchy (A > B > C but C > A). A variety of mathematical models suggests that intransitive networks can prevent or slow down competitive exclusion and maintain biodiversity by enhancing species coexistence. However, it has been difficult to assess empirically the relative importance of intransitive competition because a large number of pairwise species competition experiments are needed to construct a competition matrix that is used to parameterize existing models. Here we introduce a statistical framework for evaluating the contribution of intransitivity …
Using Historical And Experimental Data To Reveal Warming Effects On Ant Assemblages, Julian Resasco, Shannon L. Pelini, Katharine L. Stuble, Nathan J. Sanders, Robert R. Dunn, Sarah E. Diamond, Aaron M. Ellison, Nicholas J. Gotelli, Douglas J. Levey
Using Historical And Experimental Data To Reveal Warming Effects On Ant Assemblages, Julian Resasco, Shannon L. Pelini, Katharine L. Stuble, Nathan J. Sanders, Robert R. Dunn, Sarah E. Diamond, Aaron M. Ellison, Nicholas J. Gotelli, Douglas J. Levey
College of Arts and Sciences Faculty Publications
Historical records of species are compared with current records to elucidate effects of recent climate change. However, confounding variables such as succession, land-use change, and species invasions make it difficult to demonstrate a causal link between changes in biota and changes in climate. Experiments that manipulate temperature can overcome this issue of attribution, but long-term impacts of warming are difficult to test directly. Here we combine historical and experimental data to explore effects of warming on ant assemblages in southeastern US. Observational data span a 35-year period (1976-2011), during which mean annual temperatures had an increasing trend. Mean summer temperatures …
Rarefaction And Extrapolation With Hill Numbers: A Framework For Sampling And Estimation In Species Diversity Studies, Anne Chao, Nicholas J. Gotelli, T. C. Hsieh, Elizabeth L. Sander, K. H. Ma, Robert K. Colwell, Aaron M. Ellison
Rarefaction And Extrapolation With Hill Numbers: A Framework For Sampling And Estimation In Species Diversity Studies, Anne Chao, Nicholas J. Gotelli, T. C. Hsieh, Elizabeth L. Sander, K. H. Ma, Robert K. Colwell, Aaron M. Ellison
College of Arts and Sciences Faculty Publications
Quantifying and assessing changes in biological diversity are central aspects of many ecological studies, yet accurate methods of estimating biological diversity from sampling data have been elusive. Hill numbers, or the effective number of species, are increasingly used to characterize the taxonomic, phylogenetic, or functional diversity of an assemblage. However, empirical estimates of Hill numbers, including species richness, tend to be an increasing function of sampling effort and, thus, tend to increase with sample completeness. Integrated curves based on sampling theory that smoothly link rarefaction (interpolation) and prediction (extrapolation) standardize samples on the basis of sample size or sample completeness …
A Framework For Evaluating The Influence Of Climate, Dispersal Limitation, And Biotic Interactions Using Fossil Pollen Associations Across The Late Quaternary, Jessica L. Blois, Nicholas J. Gotelli, Anna K. Behrensmeyer, J. Tyler Faith, S. Kathleen Lyons, John W. Williams, Kathryn L. Amatangelo, Antoine Bercovici, Andrew Du, Jussi T. Eronen, Gary R. Graves, Nathan Jud, Conrad Labandeira, Cindy V. Looy, Brian Mcgill, David Patterson, Richard Potts, Brett Riddle, Rebecca Terry, Anikó Tóth, Amelia Villaseñor, Scott Wing
A Framework For Evaluating The Influence Of Climate, Dispersal Limitation, And Biotic Interactions Using Fossil Pollen Associations Across The Late Quaternary, Jessica L. Blois, Nicholas J. Gotelli, Anna K. Behrensmeyer, J. Tyler Faith, S. Kathleen Lyons, John W. Williams, Kathryn L. Amatangelo, Antoine Bercovici, Andrew Du, Jussi T. Eronen, Gary R. Graves, Nathan Jud, Conrad Labandeira, Cindy V. Looy, Brian Mcgill, David Patterson, Richard Potts, Brett Riddle, Rebecca Terry, Anikó Tóth, Amelia Villaseñor, Scott Wing
College of Arts and Sciences Faculty Publications
Environmental conditions, dispersal lags, and interactions among species are major factors structuring communities through time and across space. Ecologists have emphasized the importance of biotic interactions in determining local patterns of species association. In contrast, abiotic limits, dispersal limitation, and historical factors have commonly been invoked to explain community structure patterns at larger spatiotemporal scales, such as the appearance of late Pleistocene no-analog communities or latitudinal gradients of species richness in both modern and fossil assemblages. Quantifying the relative influence of these processes on species co-occurrence patterns is not straightforward. We provide a framework for assessing causes of species associations …
A Cosmogenic View Of Erosion, Relief Generation, And The Age Of Faulting In Southern Africa, Paul R. Bierman, Ryan Coppersmith, Kathryn Hanson, Johann Neveling, Eric W. Portenga, Dylan H. Rood
A Cosmogenic View Of Erosion, Relief Generation, And The Age Of Faulting In Southern Africa, Paul R. Bierman, Ryan Coppersmith, Kathryn Hanson, Johann Neveling, Eric W. Portenga, Dylan H. Rood
College of Arts and Sciences Faculty Publications
Southernmost Africa, with extensive upland geomorphic surfaces, deep canyons, and numerous faults, has long interested geoscientists. A paucity of dates and low rates of background seismicity make it challenging to quantify the pace of landscape change and determine the likelihood and timing of fault movement that could raise and lower parts of the landscape and create associated geohazards. To infer regional rates of denudation, we measured 10Be in river sediment samples and found that south-central South Africa is eroding ∼5 m m.y.-1, a slow erosion rate consistent with those measured in other non-tectonically active areas, including much of southern Africa. …
P Values, Hypothesis Testing, And Model Selection: It's Déjà Vu All Over Again, Aaron M. Ellison, Nicholas J. Gotelli, Brian D. Inouye, Donald R. Strong
P Values, Hypothesis Testing, And Model Selection: It's Déjà Vu All Over Again, Aaron M. Ellison, Nicholas J. Gotelli, Brian D. Inouye, Donald R. Strong
College of Arts and Sciences Faculty Publications
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