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Abstract 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.
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Predicting plant species climate niches on the basis of mechanistic traits
Abstract Improved estimation of climate niches is critical, given climate change. Plant adaptation to climate depends on their physiological traits and their distributions, yet traits are rarely used to inform the estimation of species climate niches, and the power of a trait‐based approach has been controversial, given the many ecological factors and methodological issues that may result in decoupling of species' traits from their native climate.For 107 species across six ecosystems of California, we tested the hypothesis that mechanistic leaf and wood traits can robustly predict the mean of diverse species' climate distributions, when combining methodological improvements from previous studies, including standard trait measurements and sampling plants growing together at few sites. Further, we introduce an approach to quantify species' trait‐climate mismatch.We demonstrate a strong power to predict species mean climate from traits. As hypothesized, the prediction of species mean climate is stronger (and mismatch lower) when traits are sampled for individuals closer to species' mean climates.Improved resolution of species' climate niches based on mechanistic traits can importantly inform conservation of vulnerable species under the threat of climatic shifts in upcoming decades. Read the freePlain Language Summaryfor this article on the Journal blog.
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- PAR ID:
- 10465298
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Functional Ecology
- Volume:
- 37
- Issue:
- 11
- ISSN:
- 0269-8463
- Format(s):
- Medium: X Size: p. 2786-2808
- Size(s):
- p. 2786-2808
- Sponsoring Org:
- National Science Foundation
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