National Center for Ecological Analysis And Synthesis
National Center for Ecological Analysis And Synthesis
The National Center for Ecological Analysis and Synthesis is a research center at the University of California, Santa Barbara, in Santa Barbara, California. Better known by its acronym, NCEAS opened in May 1995. Funding for NCEAS is diverse and includes supporters such as the U.S. National Science Foundation, the State of California, and the University of California, Santa Barbara.NCEAS supports cross-disciplinary research that analyzes and synthesizes existing data to address major fundamental issues in ecology and allied fields, and encourages the application of science to natural resource management and public policy decision making. To facilitate synthetic analysis, NCEAS advances new techniques in mathematical and geospatial modeling, dynamic simulation, and visualization of ecological systems through its Ecoinformatics program. Since its inception, the Center has hosted over 5,000 individuals and supported roughly 500 research projects, which have resulted in more than 2,000 publications in 300+ different journals. In addition, NCEAS engages graduate students and grade school children through a variety of outreach and education programs. Wikipedia.
Williams N.M.,University of California at Davis |
Regetz J.,National Center for Ecological Analysis And Synthesis |
Kremen C.,University of California at Berkeley
Ecology | Year: 2012
Variation in the availability of food resources over space and time is a likely driver of how landscape structure and composition affect animal populations. Few studies, however, have directly assessed the spatiotemporal variation in resource availability that arises from landscape pattern, or its effect on populations and population dynamic parameters. We tested the effect of floral resource availability at the landscape scale on the numbers of worker, male, and queen offspring produced by bumble bee, Bombus vosnesenskii, colonies experimentally placed within complex agricultural-natural landscapes. We quantified flower densities in all land use types at different times of the season and then used these data to calculate spatially explicit estimates of floral resources surrounding each colony. Floral availability strongly correlated with landscape structure, and different regions of the landscape showed distinct seasonal patterns of floral availability. The floral resources available in the landscape surrounding a colony positively affected the number of workers and males it produced. Production was more sensitive to early-than to later-season resources. Floral resources did not significantly affect queen production despite a strong correlation between worker number and queen number among colonies. No landscape produced high floral resources during both the early and late season, and seasonal consistency is likely required for greater queen production. Floral resources are important determinants of colony growth and likely affect the pollination services provided by bumble bees at a landscape scale. Spatiotemporal variation in floral resources across the landscape precludes a simple relationship between resources and reproductive success as measured by queens, but nonetheless likely influences the total abundance of bumble bees in our study region. © 2012 by the Ecological Society of America.
Goldberg E.E.,University of Illinois at Chicago |
Lancaster L.T.,National Center for Ecological Analysis And Synthesis |
Ree R.H.,Field Museum of Natural History
Systematic Biology | Year: 2011
Geographic characters-traits describing the spatial distribution of a species-may both affect and be affected by processes associated with lineage birth and death. This is potentially confounding to comparative analyses of species distributions because current models do not allow reciprocal interactions between the evolution of ranges and the growth of phylogenetic trees. Here, we introduce a likelihood-based approach to estimating region-dependent rates of speciation, extinction, and range evolution from a phylogeny, using a new model in which these processes are interdependent. We demonstrate the method with simulation tests that accurately recover parameters relating to the mode of speciation and source-sink dynamics. We then apply it to the evolution of habitat occupancy in Californian plant communities, where we find higher rates of speciation in chaparral than in forests and evidence for expanding habitat tolerances. © The Author(s) 2011. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved.
Balch J.K.,Pennsylvania State University |
Balch J.K.,National Center for Ecological Analysis And Synthesis |
Bradley B.A.,University of Massachusetts Amherst |
D'Antonio C.M.,University of California at Santa Barbara |
Gomez-Dans J.,University College London
Global Change Biology | Year: 2013
Non-native, invasive grasses have been linked to altered grass-fire cycles worldwide. Although a few studies have quantified resulting changes in fire activity at local scales, and many have speculated about larger scales, regional alterations to fire regimes remain poorly documented. We assessed the influence of large-scale Bromus tectorum (hereafter cheatgrass) invasion on fire size, duration, spread rate, and interannual variability in comparison to other prominent land cover classes across the Great Basin, USA. We compared regional land cover maps to burned area measured using the Moderate Resolution Imaging Spectroradiometer (MODIS) for 2000-2009 and to fire extents recorded by the USGS registry of fires from 1980 to 2009. Cheatgrass dominates at least 6% of the central Great Basin (650 000 km2). MODIS records show that 13% of these cheatgrass-dominated lands burned, resulting in a fire return interval of 78 years for any given location within cheatgrass. This proportion was more than double the amount burned across all other vegetation types (range: 0.5-6% burned). During the 1990s, this difference was even more extreme, with cheatgrass burning nearly four times more frequently than any native vegetation type (16% of cheatgrass burned compared to 1-5% of native vegetation). Cheatgrass was also disproportionately represented in the largest fires, comprising 24% of the land area of the 50 largest fires recorded by MODIS during the 2000s. Furthermore, multi-date fires that burned across multiple vegetation types were significantly more likely to have started in cheatgrass. Finally, cheatgrass fires showed a strong interannual response to wet years, a trend only weakly observed in native vegetation types. These results demonstrate that cheatgrass invasion has substantially altered the regional fire regime. Although this result has been suspected by managers for decades, this study is the first to document recent cheatgrass-driven fire regimes at a regional scale. © 2012 Blackwell Publishing Ltd.
Killen S.S.,Montpellier University |
Atkinson D.,University of Liverpool |
Atkinson D.,National Center for Ecological Analysis And Synthesis |
Glazier D.S.,Juniata College
Ecology Letters | Year: 2010
Metabolic energy fuels all biological processes, and therefore theories that explain the scaling of metabolic rate with body mass potentially have great predictive power in ecology. A new model, that could improve this predictive power, postulates that the metabolic scaling exponent (b) varies between 2/3 and 1, and is inversely related to the elevation of the intraspecific scaling relationship (metabolic level, L), which in turn varies systematically among species in response to various ecological factors. We test these predictions by examining the effects of lifestyle, swimming mode and temperature on intraspecific scaling of resting metabolic rate among 89 species of teleost fish. As predicted, b decreased as L increased with temperature, and with shifts in lifestyle from bathyal and benthic to benthopelagic to pelagic. This effect of lifestyle on b may be related to varying amounts of energetically expensive tissues associated with different capacities for swimming during predator-prey interactions. © 2009 Blackwell Publishing Ltd/CNRS.
Alroy J.,National Center for Ecological Analysis And Synthesis |
Alroy J.,Macquarie University
Palaeontology | Year: 2010
The Paleobiology Database now includes enough data on fossil collections to produce useful time series of geographical and environmental variables in addition to a robust global Phanerozoic marine diversity curve. The curve is produced by a new 'shareholder quorum' method of sampling standardization that removes biases but avoids overcompensating for them by imposing entirely uniform data quotas. It involves drawing fossil collections until the taxa that have been sampled at least once (the 'shareholders') have a summed total of frequencies (i.e. coverage) that meets a target (the 'quorum'). Coverage of each interval's entire data set is estimated prior to subsampling using a variant of a standard index, Good's u. This variant employs counts of occurrences of taxa described in only one publication instead of taxa found in only one collection. Each taxon's frequency within an interval is multiplied by the interval's index value, which limits the maximum possible sampling level and thereby creates the need for subsampling. Analyses focus on a global diversity curve and curves for northern, southern and 'tropical' (30°N to 30°S) palaeolatitudinal belts. Tropical genus richness is remarkably static, so most large shifts in the curve reflect trends at higher latitudes. Changes in diversity are analysed as a function of standing diversity; the number, spacing and palaeolatitudinal position of sampled geographical cells; the mean onshore-offshore position of cells; and proportions of cells from carbonate, onshore and reefal environments. Redundancy among the variables is eliminated by performing a principal components analysis of each data set and using the axis scores in multiple regressions. The key factors are standing diversity and the dominance of onshore environments such as reefs. These factors combine to produce logistic growth patterns with slowly changing equilibrium values. There is no evidence of unregulated exponential growth across any long stretch of the Phanerozoic, and in particular there was no large Cenozoic radiation beyond the Eocene. The end-Ordovician, Permo-Triassic and Cretaceous-Palaeogene mass extinctions had relatively short-term albeit severe effects. However, reef collapse was involved in these events and also may have caused large, longer term global diversity decreases in the mid-Devonian and across the Triassic/Jurassic boundary. Conversely, the expansion of reef ecosystems may explain newly recognized major radiations in the mid-Permian and mid-Jurassic. Reef ecosystems are particularly vulnerable to current environmental disturbances such as ocean acidification, and their decimation might prolong the recovery from today's mass extinction by millions or even tens of millions of years. © The Palaeontological Association.
Hampton S.E.,National Center for Ecological Analysis And Synthesis |
Parker J.N.,Arizona State University
BioScience | Year: 2011
Scientific synthesis has transformed ecological research and presents opportunities for advancements across the sciences; to date, however, little is known about the antecedents of success in synthesis. Building on findings from 10 years of detailed research on social interactions in synthesis groups at the National Center for Ecological Analysis and Synthesis, we demonstrated with large-scale quantitative analyses that face-to-face interaction has been vital to success in synthesis groups, boosting the production of peer-reviewed publications. But it has been about more than just meeting; the importance of resident scientists at synthesis centers was also evident, in that including synthesis-center residents in geographically distributed working groups further increased productivity. Moreover, multi-institutional collaboration, normally detrimental to productivity, was positively associated with productivity in this stimulating environment. Finally, participation in synthesis groups significantly increased scientists' collaborative propensity and visibility, positively affecting scientific careers and potentially increasing the capacity of the scientific community to leverage synthesis for enhanced scientific understanding. © 2011 by American Institute of Biological Sciences. All rights reserved.
Lancaster L.T.,National Center for Ecological Analysis And Synthesis
BMC Evolutionary Biology | Year: 2010
Background. A positive relationship between diversification (i.e., speciation) and nucleotide substitution rates is commonly reported for angiosperm clades. However, the underlying cause of this relationship is often unknown because multiple intrinsic and extrinsic factors can affect the relationship, and these have confounded previous attempts infer causation. Determining which factor drives this oft-reported correlation can lend insight into the macroevolutionary process. Results. Using a new database of 13 time-calibrated angiosperm phylogenies based on internal transcribed spacer (ITS) sequences, and controlling for extrinsic variables of life history and habitat, I evaluated several potential intrinsic causes of this correlation. Speciation rates () and relative extinction rates () were positively correlated with mean substitution rates, but were uncorrelated with substitution rate heterogeneity. It is unlikely that the positive diversification-substitution correlation is due to accelerated molecular evolution during speciation (e.g., via enhanced selection or drift), because punctuated increases in ITS rate (i.e., greater mean and variation in ITS rate for rapidly speciating clades) were not observed. Instead, fast molecular evolution likely increases speciation rate (via increased mutational variation as a substrate for selection and reproductive isolation) but also increases extinction (via mutational genetic load). Conclusions. In general, these results predict that clades with higher background substitution rates may undergo successful diversification under new conditions while clades with lower substitution rates may experience decreased extinction during environmental stasis. © 2010 Lancaster; licensee BioMed Central Ltd.
Sagarin R.D.,University of Arizona |
Turnipseed M.,National Center for Ecological Analysis And Synthesis
Annual Review of Environment and Resources | Year: 2012
The public trust doctrine (PTD) is a legal concept with ancient roots, and it is increasingly being examined as a framework for modern conservation. At its core, the PTD is based on the idea that certain natural resources cannot be fairly or effectively managed by private owners. Rather, these resources should be held in trust by government, which must manage their consumptive use and protection on behalf of present and future citizens. Although historically the PTD applied to a limited set of natural resources such as shellfish beds and submerged lands, courts and legal scholars have expanded the definition of trust resources to include wildlife, oceans, and ecosystem services generally. The wide range of interpretations of the PTD is seen as both a weakness (because it leads to uncertainty in property ownership) and a strength (because it can adapt to accommodate emerging science about what it takes to protect ecosystems). © Copyright ©2012 by Annual Reviews. All rights reserved.
Wolkovich E.M.,National Center for Ecological Analysis And Synthesis |
Cleland E.E.,University of California at San Diego
Frontiers in Ecology and the Environment | Year: 2011
Community ecologists have long recognized the importance of phenology (the timing of periodic life-history events) in structuring communities. Phenological differences between exotic and native species may contribute to the success of invaders, yet a general theory for how phenology may shape invasions has not been developed. Shifts toward longer growing seasons, tracked by plant and animal species worldwide, heighten the need for this analysis. The concurrent availability of extensive citizen-science and long-term datasets has created tremendous opportunities to test the relationship between phenology and invasion. Here, we (1) extend major theories within community and invasion biology to include phenology, (2) develop a predictive framework to test these theories, and (3) outline available data resources to test predictions. By creating an integrated framework, we show how new analyses of long-term datasets could advance the fields of community ecology and invasion biology, while developing novel strategies for invasive species management. Although we focus here on terrestrial plants, our framework has clear extensions to animal communities and aquatic ecosystems as well. © The Ecological Society of America.
Wilson E.E.,University of California at San Diego |
Wolkovich E.M.,National Center for Ecological Analysis And Synthesis
Trends in Ecology and Evolution | Year: 2011
Recent advances in the ecology of food webs underscore the importance of detritus and indirect predator-prey effects. However, most research considers detritus as an invariable pool and predation as the only interaction between carnivores and prey. Carrion consumption, scavenging, is a type of detrital feeding that should have widespread consequences for the structure and stability of food webs. Providing access to high-quality resources, facultative scavenging is a ubiquitous and phylogenetically widespread strategy. In this review, we argue that scavenging is underestimated by 16-fold in food-web research, producing inflated predation rates and underestimated indirect effects. Furthermore, more energy is generally transferred per link via scavenging than predation. Thus, future food-web research should consider scavenging, especially in light of how major global changes can affect scavengers. © 2010 Elsevier Ltd.