Standardized NEON organismal data for biodiversity research

Abiotic variables drive different aspects of fish community trait variation and species richness across the continental United States

Intraspecific trait variation (ITV) is an increasingly important aspect of biodiversity and can provide a more complete perspective on how abiotic and biotic processes affect individuals, species' niches and ultimately community-level structure than traditional uses of trait means. Body size serves as a proxy for a suite of traits that govern species' niches. Distributions of co-occurring species body sizes can inform niche overlap, relate to species richness and uncover mechanistic drivers of diversity. We leveraged individual-level body size (length) in freshwater fishes and environmental data from the National Ecological Observatory Network (NEON) for 17 lakes and streams in the contiguous United States to explore how abiotic and biotic factors influence fish species richness and trait distributions of body size. We calculated key abiotic (climate, productivity, land use) and biotic (phylogenetic diversity, trait diversity, community-level overlap of trait probability densities) variables for each site to test hypotheses about drivers of ITV in body size and fish diversity. Abiotic variables were consistently important in explaining variation in fish body size and species richness across sites. In particular, productivity (as chlorophyll) was a key variable in explaining variation in body size trait richness, evenness and divergence, as well as species richness. This study yields new insights into continental-scale patterns of freshwater fishes, possible only by leveraging the paired high frequency, in situ abiotic data and individual-level traits collected by NEON.

Functional reorganization of North American wintering avifauna

Wintering birds serve as vital climate sentinels, yet they are often overlooked in studies of avian diversity change. Here, we provide a continental-scale characterization of change in multifaceted wintering avifauna and examine the effects of climate change on these dynamics. We reveal a strong functional reorganization of wintering bird communities marked by a north-south gradient in functional diversity change, along with a superimposed mild east-west gradient in trait composition change. Assemblages in the northern United States saw contractions of the functional space and increases in functional evenness and originality, while the southern United States saw smaller contractions of the functional space and stasis in evenness and originality. Shifts in functional diversity were underlined by significant reshuffling in trait composition, particularly pronounced in the western and northern United States. Finally, we find strong contributions of climate change to this functional reorganization, underscoring the importance of wintering birds in tracking climate change impacts on biodiversity.

A slow-fast trait continuum at the whole community level in relation to land-use intensification

Organismal functional strategies form a continuum from slow- to fast-growing organisms, in response to common drivers such as resource availability and disturbance. However, whether there is synchronisation of these strategies at the entire community level is unclear. Here, we combine trait data for >2800 above- and belowground taxa from 14 trophic guilds spanning a disturbance and resource availability gradient in German grasslands. The results indicate that most guilds consistently respond to these drivers through both direct and trophically mediated effects, resulting in a 'slow-fast' axis at the level of the entire community. Using 15 indicators of carbon and nutrient fluxes, biomass production and decomposition, we also show that fast trait communities are associated with faster rates of ecosystem functioning. These findings demonstrate that 'slow' and 'fast' strategies can be manifested at the level of whole communities, opening new avenues of ecosystem-level functional classification.

Understanding Organisms Using Ecological Observatory Networks

Human activities are rapidly changing ecosystems around the world. These changes have widespread implications for the preservation of biodiversity, agricultural productivity, prevalence of zoonotic diseases, and sociopolitical conflict. To understand and improve the predictive capacity for these and other biological phenomena, some scientists are now relying on observatory networks, which are often composed of systems of sensors, teams of field researchers, and databases of abiotic and biotic measurements across multiple temporal and spatial scales. One well-known example is NEON, the US-based National Ecological Observatory Network. Although NEON and similar networks have informed studies of population, community, and ecosystem ecology for years, they have been minimally used by organismal biologists. NEON provides organismal biologists, in particular those interested in NEON's focal taxa, with an unprecedented opportunity to study phenomena such as range expansions, disease epidemics, invasive species colonization, macrophysiology, and other biological processes that fundamentally involve organismal variation. Here, we use NEON as an exemplar of the promise of observatory networks for understanding the causes and consequences of morphological, behavioral, molecular, and physiological variation among individual organisms.