Matthew R Helmus

Temple University | TU · Department of Biology

Long-distance colonization was once rare causing species within regions to be closely related. Now, in the Anthropocene, biogeographic structure is being eroded by species introductions. Here, we contrast the ecology and evolution of native versus exotic Caribbean Anolis lizards and show that the once strong biogeographic structure in the clade has...

Ecosystems are fragmented by natural and anthropogenic processes that affect organism movement and ecosystem dynamics. When a fragmentation restricts predator but not prey movement, then the prey produced on one side of an ecosystem edge can subsidize predators on the other side. When prey flux is high, predator density on the receiving side increa...

Phylogenetic diversity—area curves are analogous to species—area curves and quantify the relationship between the phylogenetic diversity of species assemblages and the area over which assemblages are sampled. Here, we developed theoretical expectations of these curves under different ecological and macroevolutionary processes. We first used simulat...

For centuries, biogeographers have examined the factors that produce patterns of biodiversity across regions. The study of islands has proved particularly fruitful and has led to the theory that geographic area and isolation influence species colonization, extinction and speciation such that larger islands have more species and isolated islands hav...

Ecology Letters (2010) 13: 162–174 Predicting community and species responses to disturbance is complicated by incomplete knowledge about species traits. A phylogenetic framework should partially solve this problem, as trait similarity is generally correlated with species relatedness, closely related species should have similar sensitivities to dis...

In the Anthropocene, the ranges of introduced species are expanding, while extinction‐prone species are contracting. Introductions and extinctions are caused by how species respond to human impacts, but it is unknown why the ranges of some species expand and some contract. Here, we test whether this opposite response of human impact is due to intro...

Islands harbor a significant proportion of global biodiversity and also have disproportionately high richness of introduced species relative to continents. Given the sensitivity of island ecosystems to introduced species, data deficiencies on introduction pathways, patterns of establishment, and potential impacts of introduced species can hamper mi...

Aim The development of natural habitats into urban land uses has greatly accelerated in the recent past due to human activities. This habitat development disrupts species' natural dispersal processes and can lead to both direct and indirect impacts on dispersal. Whether human activities result in restricted or facilitated dispersal may depend on a...

Temperature time series data are a composition of average trends and stochastic variability that together shape population dynamics. However, models of temperature-dependent species often overlook variability, focusing solely on growth rate under average conditions. When models omit variability, they can inaccurately predict the dynamics that under...

A crucial asset in the management of invasive species is the open-access sharing of data on the range of invaders and the progression of their spread. Such data should be current, comprehensive, consistent and standardised, to support reproducible and comparable forecasting efforts amongst multiple researchers and managers. Here, we present the lyd...

A crucial asset in the management of invasive species is the open-access sharing of data on the range of invaders and the progression of their spread. Such data should be current, comprehensive, consistent, and standardized, to support reproducible and comparable forecasting efforts among multiple researchers and managers. Here, we present the lyde...

Control of incipient invaders—established invasive species in the early stages of spreading—can be inhibited by incomplete knowledge of the species' habitat use. By identifying consistent habitat associations for incipient invaders early, control efforts can be more effective. Yet, because habitat associations are the result of multiscale processes...

A major challenge in invasion ecology is determining which introduced species pose a threat to resident species through competitive displacement. Here, we provide a statistical framework rooted in coexistence theory to calculate coexistence outcomes, including competitive displacement, between resident and invading species. Advantageously, our fram...

The species-area relationship (SAR) is a fundamental pattern of island biogeography which is often curvilinear due to reduced accumulation of species on mid-sized island caused by island isolation and the lack of speciation present on larger islands. The curvature of SARs represents lower saturation of species on mid-sized islands and therefore acc...

Aim Island biogeography theory states that species richness increases with habitat diversity and decreases with isolation from source pools. However, ecological theory must incorporate effects of human activity to explain contemporary patterns of biodiversity. We contemporized island biogeography theory by conceptualizing island trajectories of how...

Aim : Island biogeography theory states that species richness increases with habitat diversity and decreases with isolation from source pools. However, ecological theory must incorporate effects of human activity to explain contemporary patterns of biodiversity. We contemporized island biogeography theory by conceptualizing island trajectories of h...

Invasive pest establishment is a pervasive threat to global ecosystems, agriculture, and public health. The recent establishment of the invasive spotted lanternfly in the northeastern United States has proven devastating to farms and vineyards, necessitating urgent development of population dynamical models and effective control practices. In this...

Global impacts of invasive insect pests cost billions of dollars annually, but the impact of any individual pest species depends on the strength of associations with economically important plant hosts. Estimating host associations for a pest requires surveillance field surveys that observe pest association on plant species within an invaded area. H...

The selective landscape that gave rise to Earth's species has shifted in the Anthropocene. Humans have accelerated extinction pressures, making efforts to detect general non-random patterns of extinction increasingly important. Much research has focused on detecting which traits make some species more likely to go extinct, such as large body size a...

1. Control of incipient invaders, established invasive species in the early stages of spreading, can be inhibited by incomplete knowledge of the species' habitat use. By identifying consistent habitat associations for incipient invaders early, control efforts can be more effective. Yet, because habitat associations are the result of multiscale proc...

Understanding patterns and drivers of species distribution and abundance, and thus biodiversity, is a core goal of ecology. Despite advances in recent decades, research into these patterns and processes is currently limited by a lack of standardized, high‐quality, empirical data that span large spatial scales and long time periods. The NEON fills t...

Economic impacts from plant pests are often felt at the regional scale, yet some impacts expand to the global scale through the alignment of a pest’s invasion potentials. Such globally invasive species (i.e., paninvasives) are like the human pathogens that cause pandemics. Like pandemics, assessing paninvasion risk for an emerging regional pest is...

Economic impacts from plant pests are often felt at the regional scale, yet some impacts expand to the global scale through the alignment of a pest’s invasion potentials. Such globally invasive species (i.e., paninvasives) are like the human pathogens that cause pandemics. Like pandemics, assessing paninvasion risk for an emerging regional pest is...

Human activity has greatly accelerated in the past century impacting biodiversity across the globe. To accurately explain contemporary patterns of biodiversity, classic ecological theory must be updated to incorporate the effects of this Great Acceleration on biodiversity. We contemporized island biogeographic theory (IBT) and its extension, the ge...

Trees provide critical contributions to human well-being. They sequester and store greenhouse gasses, filter air pollutants, provide wood, food, and other products, among other benefits. These benefits are threatened by climate change, fires, pests and pathogens. To quantify the current value of the flow of ecosystem services from U.S. trees, and t...

Understanding the drivers of community stability in times of increasing anthropogenic pressure is an urgent issue. Biodiversity is known to promote community stability, but studies of the biodiversity–stability relationship rarely consider the full complexity of biodiversity change. Furthermore, finding generalities that hold across taxonomic group...

The Anthropocene is marked by unprecedented changes to species ranges worldwide. Introduced species expand their native range into new geographic regions while extinction-prone species experience severe native range contraction. Introductions and extinctions are both caused by how species respond to human influence within their native ranges. The q...

Sharing ecological research with stakeholders has broader impacts for conservation and sustainability outcomes. However, ecologists face major challenges to effective communication with stakeholders, including lack of reciprocal trust, unacknowledged incentives, differing goals, and scientific inaccessibility. These obstacles largely stem from prof...

Invasive pest establishment is a pervasive threat to global ecosystems, agriculture, and public health. The recent establishment of the invasive spotted lanternfly in the northeastern United States has proven devastating to farms and vineyards, necessitating urgent development of population dynamical models and effective control practices. In this...

Classic ecological theory must explain effects of humans on biodiversity to be more applicable today. We contemporized island biogeographic theory providing native, introduced, and total species richness relationship expectations with natural and anthropogenic metrics of habitat diversity (geographic and economic area) and isolation from source poo...

It is a critical time to reflect on the National Ecological Observatory Network (NEON) science to date as well as envision what research can be done right now with NEON (and other) data and what training is needed to enable a diverse user community. NEON became fully operational in May 2019 and has pivoted from planning and construction to operatio...

The functioning of present ecosystems reflects deep evolutionary history of locally cooccurring species if their functional traits show high phylogenetic signal (PS). However, we do not understand what drives local PS. We hypothesize that local PS is high in undisturbed and stressful habitats, either due to ongoing local assembly of species that ma...

Understanding patterns and drivers of species distributions and abundances, and thus biodiversity, is a core goal of ecology. Despite advances in recent decades, research into these patterns and processes is currently limited by a lack of standardized, high-quality, empirical data that spans large spatial scales and long time periods. The National...

During the 21st century, human–environment interactions will increasingly expose both systems to risks, but also yield opportunities for improvement as we gain insight into these complex, coupled systems. Human–environment interactions operate over multiple spatial and temporal scales, requiring large data volumes of multi‐resolution information fo...

Model‐based approaches are increasingly popular in ecological studies. A good example of this trend is the use of joint species distribution models to ask questions about ecological communities. However, most current applications of model‐based methods do not include phylogenies despite the well‐known importance of phylogenetic relationships in sha...

Urban development and species invasion are two major global threats to biodiversity. These threats often co‐occur, as developed areas are more prone to species invasion. However, few empirical studies have tested if both factors affect biodiversity in similar ways. Here we study the individual and combined effects of urban development and plant inv...

Model-based approaches are increasingly popular in ecological studies. A good example of this trend is the use of joint species distribution models to ask questions about ecological communities. However, most current applications of model-based methods do not include phylogenies despite the well-known importance of phylogenetic relationships in sha...

Vegetated green infrastructure (GI) is used as a sustainable complement to traditional stormwater infrastructure in many cities and is reported to provide additional benefits such as heat island mediation, crime reduction, increased property values, improved air quality, improved human well-being, improved aesthetics, biodiversity conservation, and...

Trees provide critical contributions to human well-being. They sequester and store greenhouse gasses, filter air pollutants, and provide wood, food, and other products, among other benefits. However, global change threatens these benefits. To quantify the monetary value of US trees and the threats they face, we combine macroevolutionary and economi...

Globally, geckos (Gekkonidae) are one of the most successful reptile families for exotic species. With the exception of the widespread invader, Hemidactylus mabouia, however, introductions of exotic gecko species are a more recent occurrence in the Caribbean islands despite extensive introductions of exotic geckos in the surrounding Caribbean regio...

Preserving the evolutionary history and ecological functions that different species embody, in addition to species themselves, is a growing concern for conservation. Recent studies warn that conservation priority regions identified using species diversity differ from those based on phylogenetic or functional diversity. However, spatial mismatches i...

Background Ecological research often involves sampling and manipulating non-model organisms that reside in heterogeneous environments. As such, ecologists often adapt techniques and ideas from industry and other scientific fields to design and build equipment, tools, and experimental contraptions custom-made for the ecological systems under study....

Human land use causes major changes in species abundance and composition, yet native and exotic species can exhibit different responses to land use change. Native populations generally decline in human‐impacted habitats while exotic species often benefit. In this study, we assessed the effects of human land use on exotic and native reptile diversit...

Background Ecological research often involves sampling and manipulating non-model organisms that reside in heterogeneous environments. As such, ecologists often adapt techniques and ideas from industry and other scientific fields to design and build equipment, tools, and experimental contraptions custom-made for the ecological systems under study....

Global variation in species richness is widely recognized, but the explanation for what drives it continues to be debated. Previous efforts have focused on a subset of potential drivers, including evolutionary rate, evolutionary time (maximum clade age of species restricted to a region), dispersal (migration from one region to another), ecological...

The geography of islands limits the natural colonization of organisms. As a result, island biodiversity is characterized by high levels of endemism. Most native species on large and geographically isolated islands are found nowhere else in the world. The intrigue of unique island species spurred the development of island biogeography theory, which...

Aim Examining the biogeography of body size is crucial for understanding how animal communities are assembled and maintained. In tetrapods, body size varies predictably with temperature, moisture, productivity seasonality and topographical complexity. Although millennial‐scale human pressures are known to have led to the extinction of primarily lar...

Increasing trade between countries and gains in income have given consumers around the world access to a richer and more diverse set of commercial plant products (i.e., foods and fibers produced by farmers). According to the economic theory of comparative advantage, countries open to trade will be able to consume more – in terms of volume and diver...

Percentage changes in trade openness and real GDP per capita by country between 1992–1994 and 2008–2010. The initial data point for each country (N = 141) is given by their 1992–1994 trade openness and real GDP per capita annual averages. The terminal data point for each country is given by their 2008–2010 trade openness and real GDP per capita ann...

Additional Materials and Methods. (DOCX)

Estimates of models (2) and (3). (DOCX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

The p and c vectors used in the text. (XLSX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

Country-level consumption PSV, SR, and E data generated with one of the 10 alternative c vectors. (XLSX)

Country-level consumption PSV, SR, and E data generated with one of the 10 alternative c vectors. (XLSX)

Country-level consumption PSV, SR, and E data generated with one of the 10 alternative c vectors. (XLSX)

Country-level consumption PSV, SR, and E data generated with one of the 10 alternative c vectors. (XLSX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

One of the 10 alternative c vectors (consumption PSV, SR, and E derived from these data are graphed in S3 Fig). (XLSX)

Country-level consumption PSV, SR, and E data generated with one of the 10 alternative c vectors. (XLSX)

Dataset used to estimate model (2) (all plants). (XLSX)

Dataset used to estimate model (3) (all plants). (XLSX)

Estimates of model (2) with contemporaneous and once and twice lagged changes in independent variables. We present six estimates of model (2) with dependent variables (defined across all plants) in the first column and contemporaneous change and once and twice lagged (L.1 and L.2, respectively) independent variables in the remaining columns where g...

Estimates of model (3) with contemporaneous and once and twice lagged changes in independent variables. We present six estimates of model (3) with dependent variables (defined across all plants) in the first column and contemporaneous change and once and twice lagged (L.1 and L.2) independent variables in the remaining columns where g indicates ann...

Model (2)’s contemporaneous marginal effects at various latitudes for all plants. The graphed contemporaneous income per capita marginal effects are equal to estimated γ1+γ2|L| and contemporaneous trade openness marginal effects are equal to estimated γ3+γ4|L| for |L| = 5, 25, 45, and 65 degrees of latitude. All marginal effects are multiplied by 1...

Sensitivity analysis of weighted mean trends in zonal consumption diversity and richness. When we calculated cjkt for each j, k, and t combination, as measured by Mg, we had to translate all processed food import and export Mg values into their constituent crop Mg using FAOStat conversion rates. For the results presented in the main text we assume...

Country-level PSV, SR, and E data used in the text (food plants only). (XLSX)

Country-level consumption PSV, SR, and E data generated with one of the 10 alternative c vectors. (XLSX)

Country-level consumption PSV, SR, and E data generated with one of the 10 alternative c vectors. (XLSX)