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Deciphering The Enigma Of Undetected Species, Phylogenetic, And Functional Diversity Based On Good-Turing Theory, Anne Chao, Chun Huo Chiu, Robert K. Colwell, Luiz Fernando S. Magnago, Robin L. Chazdon, Nicholas J. Gotelli
Deciphering The Enigma Of Undetected Species, Phylogenetic, And Functional Diversity Based On Good-Turing Theory, Anne Chao, Chun Huo Chiu, Robert K. Colwell, Luiz Fernando S. Magnago, Robin L. Chazdon, Nicholas J. Gotelli
College of Arts and Sciences Faculty Publications
Estimating the species, phylogenetic, and functional diversity of a community is challenging because rare species are often undetected, even with intensive sampling. The Good-Turing frequency formula, originally developed for cryptography, estimates in an ecological context the true frequencies of rare species in a single assemblage based on an incomplete sample of individuals. Until now, this formula has never been used to estimate undetected species, phylogenetic, and functional diversity. Here, we first generalize the Good-Turing formula to incomplete sampling of two assemblages. The original formula and its two-assemblage generalization provide a novel and unified approach to notation, terminology, and estimation of …
A Comprehensive Framework For The Study Of Species Co-Occurrences, Nestedness And Turnover, Werner Ulrich, Wojciech Kryszewski, Piotr Sewerniak, Radosław Puchałka, Giovanni Strona, Nicholas J. Gotelli
A Comprehensive Framework For The Study Of Species Co-Occurrences, Nestedness And Turnover, Werner Ulrich, Wojciech Kryszewski, Piotr Sewerniak, Radosław Puchałka, Giovanni Strona, Nicholas J. Gotelli
College of Arts and Sciences Faculty Publications
Binary presence–absence matrices (rows = species, columns = sites) are often used to quantify patterns of species co-occurrence, and to infer possible biotic interactions from these patterns. Previous classifications of co-occurrence patterns as nested, segregated, or modular have led to contradictory results and conclusions. These analyses usually do not incorporate the functional traits of the species or the environmental characteristics of the sites, even though the outcomes of species interactions often depend on trait expression and site quality. Here we address this shortcoming by developing a method that incorporates realized functional and environmental niches, and relates them to species co-occurrence …
Isolation By Distance, Not Rivers, Control The Distribution Of Termite Species In The Amazonian Rain Forest, Cristian S. Dambros, José W. Morais, Renato A. Azevedo, Nicholas J. Gotelli
Isolation By Distance, Not Rivers, Control The Distribution Of Termite Species In The Amazonian Rain Forest, Cristian S. Dambros, José W. Morais, Renato A. Azevedo, Nicholas J. Gotelli
College of Arts and Sciences Faculty Publications
The spatial distribution of species is affected by dispersal barriers, local environmental conditions and climate. However, the effect of species dispersal and their adaptation to the environment across geographic scales is poorly understood. To investigate the distribution of species from local to broad geographic scales, we sampled termites in 198 transects distributed in 13 sampling grids in the Brazilian Amazonian forest. The sampling grids encompassed an area of 271 500 km2 and included the five major biogeographic regions delimited by Amazonian rivers. Environmental data for each transect were obtained from local measurements and remote sensing. Similar to previous studies, termite …
Environmental Proteomics Reveals Taxonomic And Functional Changes In An Enriched Aquatic Ecosystem, Amanda C. Northrop, Rachel K. Brooks, Aaron M. Ellison, Nicholas J. Gotelli, Bryan A. Ballif
Environmental Proteomics Reveals Taxonomic And Functional Changes In An Enriched Aquatic Ecosystem, Amanda C. Northrop, Rachel K. Brooks, Aaron M. Ellison, Nicholas J. Gotelli, Bryan A. Ballif
College of Arts and Sciences Faculty Publications
Aquatic ecosystem enrichment can lead to distinct and irreversible changes to undesirable states. Understanding changes in active microbial community function and composition following organic matter loading in enriched ecosystems can help identify biomarkers of such state changes. In a field experiment, we enriched replicate aquatic ecosystems in the pitchers of the northern pitcher plant, Sarracenia purpurea. Shotgun metaproteomics using a custom metagenomic database identified proteins, molecular pathways, and contributing microbial taxa that differentiated control ecosystems from those that were enriched. The number of microbial taxa contributing to protein expression was comparable between treatments; however, taxonomic evenness was higher in controls. …
Identifying The Spatial Pattern And Importance Of Hydro-Geomorphic Drainage Impairments On Unpaved Roads In The Northeastern Usa, Beverley C. Wemple, Gordon E. Clark, Donald S. Ross, Donna M. Rizzo
Identifying The Spatial Pattern And Importance Of Hydro-Geomorphic Drainage Impairments On Unpaved Roads In The Northeastern Usa, Beverley C. Wemple, Gordon E. Clark, Donald S. Ross, Donna M. Rizzo
College of Arts and Sciences Faculty Publications
Roads have been widely studied as sources of runoff and sediment and identified as pollutant production sources to receiving waters. Despite the wealth of research on logging roads in forested, upland settings, little work has been conducted to examine the role of extensive networks of rural, low-volume, unpaved roads on water quality degradation at the catchment scale. We studied a network of municipal unpaved roads in the northeastern US to identify the type and spatial extent of ‘hydro-geomorphic impairments’ to water quality. We mapped erosional and depositional features on roads to develop an estimate of pollutant production. We also mapped …
Ecological Network Metrics: Opportunities For Synthesis, Matthew K. Lau, Stuart R. Borrett, Benjamin Baiser, Nicholas J. Gotelli, Aaron M. Ellison
Ecological Network Metrics: Opportunities For Synthesis, Matthew K. Lau, Stuart R. Borrett, Benjamin Baiser, Nicholas J. Gotelli, Aaron M. Ellison
College of Arts and Sciences Faculty Publications
Network ecology provides a systems basis for approaching ecological questions, such as factors that influence biological diversity, the role of particular species or particular traits in structuring ecosystems, and long-term ecological dynamics (e.g., stability). Whereas the introduction of network theory has enabled ecologists to quantify not only the degree, but also the architecture of ecological complexity, these advances have come at the cost of introducing new challenges, including new theoretical concepts and metrics, and increased data complexity and computational intensity. Synthesizing recent developments in the network ecology literature, we point to several potential solutions to these issues: integrating network metrics …
Community-Level Regulation Of Temporal Trends In Biodiversity, Nicholas J. Gotelli, Hideyasu Shimadzu, Maria Dornelas, Brian Mcgill, Faye Moyes, Anne E. Magurran
Community-Level Regulation Of Temporal Trends In Biodiversity, Nicholas J. Gotelli, Hideyasu Shimadzu, Maria Dornelas, Brian Mcgill, Faye Moyes, Anne E. Magurran
College of Arts and Sciences Faculty Publications
Many theoretical models of community dynamics predict that species richness (S) and total abundance (N) are regulated in their temporal fluctuations. We present novel evidence for widespread regulation of biodiversity. For 59 plant and animal assemblages from around the globe monitored annually for a decade or more, the majority exhibited regulated fluctuations compared to the null hypothesis of an unconstrained random walk. However, there was little evidence for statistical artifacts, regulation driven by correlations with average annual temperature, or local-scale compensatory fluctuations in S or N. In the absence of major environmental perturbations, such as urbanization or cropland transformation, species …
Heat Tolerance Predicts The Importance Of Species Interaction Effects As The Climate Changes, Sarah E. Diamond, Lacy Chick, Clint A. Penick, Lauren M. Nichols, Sara Helms Cahan, Robert R. Dunn, Aaron M. Ellison, Nathan J. Sanders, Nicholas J. Gotelli
Heat Tolerance Predicts The Importance Of Species Interaction Effects As The Climate Changes, Sarah E. Diamond, Lacy Chick, Clint A. Penick, Lauren M. Nichols, Sara Helms Cahan, Robert R. Dunn, Aaron M. Ellison, Nathan J. Sanders, Nicholas J. Gotelli
College of Arts and Sciences Faculty Publications
Few studies have quantified the relative importance of direct effects of climate change on communities versus indirect effects that are mediated thorough species interactions, and the limited evidence is conflicting. Trait-based approaches have been popular in studies of climate change, but can they be used to estimate direct versus indirect effects? At the species level, thermal tolerance is a trait that is often used to predict winners and losers under scenarios of climate change. But thermal tolerance might also inform when species interactions are likely to be important because only subsets of species will be able to exploit the available …
Tropical River Suspended Sediment And Solute Dynamics In Storms During An Extreme Drought, Kathryn E. Clark, James B. Shanley, Martha A. Scholl, Nicolas Perdrial, Julia N. Perdrial, Alain F. Plante, William H. Mcdowell
Tropical River Suspended Sediment And Solute Dynamics In Storms During An Extreme Drought, Kathryn E. Clark, James B. Shanley, Martha A. Scholl, Nicolas Perdrial, Julia N. Perdrial, Alain F. Plante, William H. Mcdowell
College of Arts and Sciences Faculty Publications
Droughts, which can strongly affect both hydrologic and biogeochemical systems, are projected to become more prevalent in the tropics in the future. We assessed the effects of an extreme drought during 2015 on stream water composition in the Luquillo Mountains of Puerto Rico. We demonstrated that drought base flow in the months leading up to the study was sourced from trade-wind orographic rainfall, suggesting a resistance to the effects of an otherwise extreme drought. In two catchments (Mameyes and Icacos), we sampled a series of four rewetting events that partially alleviated the drought. We collected and analyzed dissolved constituents (major …
Geochemical Evolution Of The Critical Zone Across Variable Time Scales Informs Concentration-Discharge Relationships: Jemez River Basin Critical Zone Observatory, Jennifer C. Mcintosh, Courtney Schaumberg, Julia Perdrial, Adrian Harpold, Angélica Vázquez-Ortega, Craig Rasmussen, David Vinson, Xavier Zapata-Rios, Paul D. Brooks, Thomas Meixner, Jon Pelletier, Louis Derry, Jon Chorover
Geochemical Evolution Of The Critical Zone Across Variable Time Scales Informs Concentration-Discharge Relationships: Jemez River Basin Critical Zone Observatory, Jennifer C. Mcintosh, Courtney Schaumberg, Julia Perdrial, Adrian Harpold, Angélica Vázquez-Ortega, Craig Rasmussen, David Vinson, Xavier Zapata-Rios, Paul D. Brooks, Thomas Meixner, Jon Pelletier, Louis Derry, Jon Chorover
College of Arts and Sciences Faculty Publications
This study investigates the influence of water, carbon, and energy fluxes on solute production and transport through the Jemez Critical Zone (CZ) and impacts on C-Q relationships over variable spatial and temporal scales. Chemical depletion-enrichment profiles of soils, combined with regolith thickness and groundwater data indicate the importance to stream hydrochemistry of incongruent dissolution of silicate minerals during deep bedrock weathering, which is primarily limited by water fluxes, in this highly fractured, young volcanic terrain. Under high flow conditions (e.g., spring snowmelt), wetting of soil and regolith surfaces and presence of organic acids promote mineral dissolution and provide a constant …
Modeling Sediment Mobilization Using A Distributed Hydrological Model Coupled With A Bank Stability Model, J. Stryker, B. Wemple, A. Bomblies
Modeling Sediment Mobilization Using A Distributed Hydrological Model Coupled With A Bank Stability Model, J. Stryker, B. Wemple, A. Bomblies
College of Arts and Sciences Faculty Publications
In addition to surface erosion, stream bank erosion and failure contributes significant sediment and sediment-bound nutrients to receiving waters during high flow events. However, distributed and mechanistic simulation of stream bank sediment contribution to sediment loads in a watershed has not been achieved. Here we present a full coupling of existing distributed watershed and bank stability models and apply the resulting model to the Mad River in central Vermont. We fully coupled the Bank Stability and Toe Erosion Model (BSTEM) with the Distributed Hydrology Soil Vegetation Model (DHSVM) to allow the simulation of stream bank erosion and potential failure in …
A Global Database Of Ant Species Abundances, Heloise Gibb, Rob R. Dunn, Nathan J. Sanders, Blair F. Grossman, Manoli Photakis, Silvia Abril, Donat Agosti, Alan N. Andersen, Elena Angulo, Inge Armbrecht, Xavier Arnan, Fabricio B. Baccaro, Tom R. Bishop, Raphaël Boulay, Carsten Brühl, Cristina Castracani, Xim Cerda, Israel Del Toro, Thibaut Delsinne, Mireia Diaz, David A. Donoso, Aaron M. Ellison, Martha L. Enriquez, Tom M. Fayle, Donald H. Feener, Brian L. Fisher, Robert N. Fisher, Matthew C. Fitzpatrick, Crisanto Gómez, Nicholas J. Gotelli, Aaron Gove
A Global Database Of Ant Species Abundances, Heloise Gibb, Rob R. Dunn, Nathan J. Sanders, Blair F. Grossman, Manoli Photakis, Silvia Abril, Donat Agosti, Alan N. Andersen, Elena Angulo, Inge Armbrecht, Xavier Arnan, Fabricio B. Baccaro, Tom R. Bishop, Raphaël Boulay, Carsten Brühl, Cristina Castracani, Xim Cerda, Israel Del Toro, Thibaut Delsinne, Mireia Diaz, David A. Donoso, Aaron M. Ellison, Martha L. Enriquez, Tom M. Fayle, Donald H. Feener, Brian L. Fisher, Robert N. Fisher, Matthew C. Fitzpatrick, Crisanto Gómez, Nicholas J. Gotelli, Aaron Gove
College of Arts and Sciences Faculty Publications
What forces structure ecological assemblages? A key limitation to general insights about assemblage structure is the availability of data that are collected at a small spatial grain (local assemblages) and a large spatial extent (global coverage). Here, we present published and unpublished data from 51, 388 ant abundance and occurrence records of more than 2,693 species and 7,953 morphospecies from local assemblages collected at 4,212 locations around the world. Ants were selected because they are diverse and abundant globally, comprise a large fraction of animal biomass in most terrestrial communities, and are key contributors to a range of ecosystem functions. …
Cosmogenic 26Al/10Be Surface Production Ratio In Greenland, Lee B. Corbett, Paul R. Bierman, Dylan H. Rood, Marc W. Caffee, Nathaniel A. Lifton, Thomas E. Woodruff
Cosmogenic 26Al/10Be Surface Production Ratio In Greenland, Lee B. Corbett, Paul R. Bierman, Dylan H. Rood, Marc W. Caffee, Nathaniel A. Lifton, Thomas E. Woodruff
College of Arts and Sciences Faculty Publications
The assumed value for the cosmogenic 26Al/10Be surface production rate ratio in quartz is an important parameter for studies investigating the burial or subaerial erosion of long-lived surfaces and sediments. Recent models and data suggest that the production ratio is spatially variable and may be greater than originally thought. Here we present measured 26Al/10Be ratios for 24 continuously exposed bedrock and boulder surfaces spanning ~61–77°N in Greenland. Empirical measurements, such as ours, include nuclides produced predominately by neutron-induced spallation with percent-level contributions by muon interactions. The slope of a York regression line fit to our data is 7.3 ± 0.3 …
Estimates Of Local Biodiversity Change Over Time Stand Up To Scrutiny, Mark Vellend, Maria Dornelas, Lander Baeten, Robin Beauséjour, Carissa D. Brown, Pieter De Frenne, Sarah C. Elmendorf, Nicholas J. Gotelli, Faye Moyes, Isla H. Myers-Smith, Anne E. Magurran, Brian J. Mcgill, Hideyasu Shimadzu, Caya Sievers
Estimates Of Local Biodiversity Change Over Time Stand Up To Scrutiny, Mark Vellend, Maria Dornelas, Lander Baeten, Robin Beauséjour, Carissa D. Brown, Pieter De Frenne, Sarah C. Elmendorf, Nicholas J. Gotelli, Faye Moyes, Isla H. Myers-Smith, Anne E. Magurran, Brian J. Mcgill, Hideyasu Shimadzu, Caya Sievers
College of Arts and Sciences Faculty Publications
We present new data and analyses revealing fundamental flaws in a critique of two recent meta-analyses of local-scale temporal biodiversity change. First, the conclusion that short-term time series lead to biased estimates of long-term change was based on two errors in the simulations used to support it. Second, the conclusion of negative relationships between temporal biodiversity change and study duration was entirely dependent on unrealistic model assumptions, the use of a subset of data, and inclusion of one outlier data point in one study. Third, the finding of a decline in local biodiversity, after eliminating post-disturbance studies, is not robust …
Competitive Interactions Change The Pattern Of Species Co-Occurrences Under Neutral Dispersal, Werner Ulrich, Franck Jabot, Nicolas J. Gotelli
Competitive Interactions Change The Pattern Of Species Co-Occurrences Under Neutral Dispersal, Werner Ulrich, Franck Jabot, Nicolas J. Gotelli
College of Arts and Sciences Faculty Publications
Non-random patterns of species segregation and aggregation within ecological communities are often interpreted as evidence for interspecific interactions. However, it is unclear whether theoretical models can predict such patterns and how environmental factors may modify the effects of species interactions on species co-occurrence. Here we extend a spatially explicit neutral model by including competitive effects on birth and death probabilities to assess whether competition alone is able to produce non-random patterns of species co-occurrence. We show that transitive and intransitive competitive hierarchies alone (in the absence of environmental heterogeneity) are indeed able to generate non-random patterns with commonly used metrics …