Nicholas J. Gotelli's research while affiliated with University of Vermont and other places

Publications (302)

Article
Full-text available
Patterns of biodiversity provide insights into the processes that shape biological communities around the world. Variation in species diversity along biogeographical or ecological gradients, such as latitude or precipitation, can be attributed to variation in different components of biodiversity: changes in the total abundance (i.e., more-individua...
Article
Full-text available
Biotic homogenization—increasing similarity of species composition among ecological communities—has been linked to anthropogenic processes operating over the last century. Fossil evidence, however, suggests that humans have had impacts on ecosystems for millennia. We quantify biotic homogenization of North American mammalian assemblages during the...
Preprint
Earth’s biodiversity continues to change rapidly through the Anthropocene ¹ , including widespread reordering of species in space 2,3 and time 4,5 . A common expectation of this reordering is that the species composition of sites is becoming increasingly similar across space, known as biotic homogenization, due to anthropogenic pressures and invasi...
Article
Biodiversity metrics often integrate data on the presence and abundance of multiple species. Yet our understanding of covariation between changes to the numbers of individuals, the evenness of species relative abundances, and the total number of species remains limited. Using individual‐based rarefaction curves, we introduce a conceptual framework...
Preprint
Patterns of biodiversity provide insights into the processes that shape biological communities around the world. Variation in species diversity along biogeographical or ecological gradients, such as latitude or precipitation, can be attributed to variation in different components of biodiversity: changes in the total abundance (i.e. more-individual...
Preprint
Patterns of biodiversity provide insights into the processes that shape biological communities around the world. Variation in species diversity along biogeographical or ecological gradients, such as latitude or precipitation, can be attributed to variation in different components of biodiversity: changes in the total abundance (i.e. more-individual...
Article
Full-text available
Social change in any society entails changes in both behaviours and institutions. We model a group-structured society in which the transmission of individual behaviour occurs in parallel with the selection of group-level institutions. We consider a cooperative behaviour that generates collective benefits for groups but does not spread between indiv...
Article
Full-text available
1. Understanding the effects of random versus niche-based processes on biodiversity patterns is a central theme in ecology, and an important tool for predicting effects of habitat loss and fragmentation on biodiversity. We investigated the predictive power of random processes to explain species richness and species dissimilarity of amphibian assemb...
Article
Aim An important research question in ecology is how climate and the biodiversity of aboveground plants and belowground microbiomes affect ecosystem functions such as nutrient pools. However, little is studied on the concurrent role of above- and belowground species composition in shaping the spatial distribution patterns of ecosystem functions acr...
Article
Full-text available
The species composition of plant and animal assemblages across the globe has changed substantially over the past century. How do the dynamics of individual species cause this change? We classified species into seven unique categories of temporal dynamics based on the ordered sequence of presences and absences that each species contributes to an ass...
Article
Understanding the causes of the generally positive relationship between biodiversity and ecosystem function (BEF) is a major research focus in ecology. Early analyses of BEF used a modification of the evolutionary Price equation to partition effects of biodiversity into components of complementarity (species richness) and dominance (species composi...
Preprint
Societies change through time, entailing changes in behaviors and institutions. We ask how social change occurs when behaviors and institutions are interdependent. We model a group-structured society in which the transmission of individual behavior occurs in parallel with the selection of group-level institutions. We consider a cooperative behavior...
Article
Full-text available
This is an open access article under the terms of the Creat ive Commo ns Attri bution-NonCo mmercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. Abstract 1. Dated, geo-referenced museum specimens are a rich data source for reconstructi...
Article
Full-text available
Understanding how species are non‐randomly distributed in space and how the resulting spatial structure responds to ecological, biogeographic, and anthropogenic drivers is a critical piece of the biodiversity puzzle. However, most metrics that quantify the spatial structure of diversity (i.e., community differentiation), such as Whittaker’s β‐diver...
Preprint
Full-text available
Biodiversity metrics often integrate data on the presence and abundance of multiple species. Yet understanding covariation of changes to the numbers of individuals, the evenness of species’ relative abundances, and the total number of species remains limited. Using individual-based rarefaction curves, we introduce a conceptual framework to understa...
Article
Full-text available
Biodiversity-both above-and belowground-influences multiple functions in terrestrial ecosystems. Yet, it is unclear whether differences in above-and belowground species composition (β-diversity) are associated with differences in multiple ecosystem functions (e.g., spatial turnover in ecosystem function). Here, we partitioned the contributions of a...
Article
Full-text available
Because ectotherm activity and metabolism are sensitive to temperature, terrestrial arthropods may be especially responsive to ongoing climatic warming. Here, we quantified responses of arthropod abundance to two years of warming in an outdoor temperature manipulation experiment at Duke Forest, North Carolina, USA. Nine open‐top chambers were indiv...
Article
The importance of climate, habitat structure, and higher trophic levels on microbial diversity is only beginning to be understood. Here, we examined the influence of climate variables, plant morphology, and the abundance of aquatic invertebrates on the microbial biodiversity of the northern pitcher plant Sarracenia purpurea. The plant's cup‐shaped...
Article
Full-text available
Incremental increases in a driver variable, such as nutrients or detritus, can trigger abrupt shifts in aquatic ecosystems that may exhibit hysteretic dynamics and a slow return to the initial state. A model system for understanding these dynamics is the microbial assemblage that inhabits the cup‐shaped leaves of the pitcher plant Sarracenia purpur...
Preprint
Full-text available
Recent renewed interest in using fossil data to understand how biotic interactions have shaped the evolution of life is challenging the widely held assumption that long-term climate changes are the primary drivers of biodiversity change. New approaches go beyond traditional richness and co-occurrence studies to explicitly model biotic interactions...
Article
Full-text available
The late Quaternary of North America was marked by prominent ecological changes, including the end-Pleistocene megafaunal extinction, the spread of human settlements and the rise of agriculture. Here we examine the mechanistic reasons for temporal changes in mammal species association and body size during this time period. Building upon the co-occu...
Article
Full-text available
Disentangling the drivers of diversity gradients can be challenging. The Measurement of Biodiversity (MoB) framework decomposes scale‐dependent changes in species diversity into three components of community structure: the species abundance distribution (SAD), the total community abundance, and the within‐species spatial aggregation. Here we extend...
Article
Many organisms are accumulating climatic debt as they respond more slowly than expected to rising global temperatures, leading to disequilibrium of species diversity with contemporary climate. The resulting transient dynamics are complex and may cause overoptimistic biodiversity assessments. We propose a simple budget framework to integrate climati...
Preprint
Full-text available
A bstract Phytotelmata, the water-filled habitats in pitcher plants, bromeliad tanks, and tree-holes, host multitrophic food webs that are model experimental systems for studying food-web structure and dynamics. However, the plant usually is considered simply as an inert container, not as an interacting part of the food web. We used a manipulative...
Preprint
Incremental increases in a driver variable, such as nutrients or detritus, can trigger abrupt shifts in aquatic ecosystems. Once these ecosystems change state, a simple reduction in the driver variable may not return them to their original state. Because of the long time scales involved, we still have a poor understanding of the dynamics of ecosyst...
Preprint
Full-text available
Biodiversity is non-randomly distributed in space and understanding how spatial structure of species diversity responds to ecological, biogeographic and anthropogenic drivers is one of the major quests of modern ecology. However, metrics of community differentiation such as Whittaker’s beta-diversity fail to unambiguously capture species turnover w...
Article
Full-text available
Protected areas are central to biodiversity conservation. For marine fish, marine protected areas (MPAs) often harbour more individuals, especially of species targeted by fisheries. But precise pathways of biodiversity change remain unclear. For example, how local‐scale responses combine to affect regional biodiversity, important for managing spati...
Preprint
Full-text available
Disentangling the drivers of diversity gradients can be challenging. The Measurement of Biodiversity (MoB) framework decomposes changes in species diversity into three components of community structure: the species abundance distribution (SAD), the total community abundance, and the within-species spatial aggregation. Here we extend MoB from catego...
Article
Full-text available
Extinction leads to restructuring By most accounts, human activities are resulting in Earth's sixth major extinction event, and large-bodied mammals are among those at greatest risk. Loss of such vital ecosystem components can have substantial impacts on the structure and function of ecological systems, yet fully understanding these effects is chal...
Article
Geographic variation in low temperatures at poleward range margins of terrestrial species often mirrors population variation in cold resistance, suggesting that range boundaries may be set by evolutionary constraints on cold physiology. The northeastern woodland ant Aphaenogaster picea occurs up to approximately 45°N in central Maine. We combined p...
Article
Full-text available
Scientists disagree about the nature of biodiversity change. While there is evidence for widespread declines from population surveys, assemblage surveys reveal a mix of declines and increases. These conflicting conclusions may be caused by the use of different metrics: assemblage metrics may average out drastic changes in individual populations. Al...
Article
Full-text available
Many species are accumulating climatic debt as they fail to keep pace with increasing global temperatures. In theory, concomitant decreases in other stressors (e.g. pollution, fragmentation) could offset some warming effects, paying climatic debt with accrued environmental credit. This process may be occurring in many western European rivers. We fi...
Article
Diversity indices have been routinely computed in the study of human microbiome-associated diseases (MADs). However, it is still unclear whether there is a consistent diversity-disease relationship (DDR) for the human MADs, and whether there are consistent differences in the taxonomic composition of microbiomes sampled from healthy versus diseased...
Article
Full-text available
Given the abundance, broad distribution, and diversity of roles that ants play in many ecosystems, they are an ideal group to serve as ecosystem indicators of climatic change. At present, only a few whole-genome sequences of ants are available (19 of >16,000 species), mostly from tropical and sub-tropical species. To address this limited sampling,...
Article
Recent studies have highlighted the importance of higher‐order competitive interactions in stabilizing population dynamics in multi‐species communities. But how does the structure of competitive hierarchies affect population dynamics and extinction processes? We tackled this important question by using spatially explicit simulations of ecological d...
Conference Paper
Large mammals are at disproportionately high risk of extinction globally, and the ecological impacts of their loss will last beyond our lifetimes. Research shows that the end-Pleistocene mass extinction of large mammals left a significant ecological legacy, from shifting vegetation and fire regimes to changes in nutrient cycling and biogeochemistry...
Article
Full-text available
The search for traits associated with plant invasiveness has yielded contradictory results, in part because most previous studies have failed to recognize that different traits are important at different stages along the introduction–naturalization–invasion continuum. Here we show that across six different habitat types in temperate Central Europe,...
Article
1.Little consensus has emerged regarding how proximate and ultimate drivers such as productivity, disturbance, and temperature may affect species richness and other aspects of biodiversity. Part of the confusion is that most studies examine species richness at a single spatial scale and ignore how the underlying components of species richness can v...
Preprint
Full-text available
Given the abundance, broad distribution, and diversity of roles that ants play in many ecosystems, they are an ideal group to serve as ecosystem indicators of climatic change. At present, only a few whole-genome sequences of ants are available (19 of > 16,000 species), mostly from tropical and sub-tropical species. To address this limited sampling,...
Article
Full-text available
Because biodiversity is multidimensional and scale‐dependent, it is challenging to estimate its change. However, it is unclear (1) how much scale‐dependence matters for empirical studies, and (2) if it does matter, how exactly we should quantify biodiversity change. To address the first question, we analysed studies with comparisons among multiple...
Article
Full-text available
Changes in environmental conditions can lead to rapid shifts in the state of an ecosystem (“regime shifts”), which, even after the environment has returned to previous conditions, subsequently recovers slowly to the previous state (“hysteresis”). Large spatial and temporal scales of dynamics, and the lack of frameworks linking observations to model...
Preprint
Full-text available
Little consensus has emerged regarding how proximate and ultimate drivers such as productivity, disturbance, and temperature may affect species richness and other aspects of biodiversity. Part of the confusion is that most studies examine species richness at a single spatial scale and ignore how the underlying components of species richness can var...
Preprint
Full-text available
Because biodiversity is multidimensional and scale-dependent, it is challenging to estimate its change. However, it is unclear (1) how much scale-dependence matters for empirical studies, and (2) if it does matter, how exactly we should quantify biodiversity change. To address the first question, we analyzed studies with comparisons among multiple...
Article
Competitive intransitivity, the existence of loops in competitive hierarchies, is one mechanism that can promote the local coexistence of competitors and maintain high local species diversity, although its prevalence and importance remain largely unknown. A full understanding of local community assembly needs knowledge of how transitive and intrans...
Preprint
Changes in environmental conditions can lead to rapid shifts in the state of an ecosystem (“regime shifts”), which, even after the environment has returned to previous conditions, subsequently recovers slowly to the previous state (“hysteresis”). Large spatial and temporal scales of dynamics, and the lack of frameworks linking observations to model...
Article
Measuring β-diversity and changes in species composition across multiple sites and environments is a major research focus in macroecology, and a variety of metrics have been proposed to quantify species co-occurrence patterns in a species × site occurrence matrix. However, indices of β-diversity and species co-occurrence are often statistically dep...
Article
Full-text available
Temperature increases associated with global climate change are likely to be accompanied by additional environmental stressors such as desiccation and food limitation, which may alter how temperature impacts organismal performance. To investigate how interactions between stressors influence thermal tolerance in the common forest ant, Aphaenogaster...
Article
A key focus in ecology is to search for community assembly rules. Here we compare two community modelling frameworks that integrate a combination of environmental and spatial data to identify positive and negative species associations from presence-absence matrices, and incorporate an additional comparison using joint species distribution models (J...
Article
Full-text available
Comparing the structure of presence/absence (i.e. binary) matrices with those of randomized counterparts is a common practice in ecology. However, differences in the randomization procedures (null models) can affect the results of the comparisons, leading matrix structural patterns to appear either ‘random’ or not. Subjectivity in the choice of one...
Article
Network analysis is increasingly widespread in ecology, with frequent questions asking which nodes (typically species) interact with one another and how strong are the interactions. Null models are a way of addressing these questions, helping to distinguish patterns driven by neutral mechanisms or sampling effects (e.g. relative abundance of differ...
Article
Full-text available
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...
Article
Full-text available
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 inc...
Article
Full-text available
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...