A1 Journal article (refereed)
Alternative measures of trait–niche relationships : A test on dispersal traits in saproxylic beetles (2023)

Burner, R. C., Stephan, J. G., Drag, L., Potterf, M., Birkemoe, T., Siitonen, J., Müller, J., Ovaskainen, O., Sverdrup‐Thygeson, A., & Snäll, T. (2023). Alternative measures of trait–niche relationships : A test on dispersal traits in saproxylic beetles. Ecology and Evolution, 13(10), Article e10588. https://doi.org/10.1002/ece3.10588

JYU authors or editors

Publication details

All authors or editors: Burner, Ryan C.; Stephan, Jörg G.; Drag, Lukas; Potterf, Mária; Birkemoe, Tone; Siitonen, Juha; Müller, Jörg; Ovaskainen, Otso; Sverdrup‐Thygeson, Anne; Snäll, Tord

Journal or series: Ecology and Evolution

eISSN: 2045-7758

Publication year: 2023

Publication date: 19/10/2023

Volume: 13

Issue number: 10

Article number: e10588

Publisher: Wiley

Publication country: United Kingdom

Publication language: English

DOI: https://doi.org/10.1002/ece3.10588

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/91235

Abstract

Functional trait approaches are common in ecology, but a lack of clear hypotheses on how traits relate to environmental gradients (i.e., trait–niche relationships) often makes uncovering mechanisms difficult. Furthermore, measures of community functional structure differ in their implications, yet inferences are seldom compared among metrics. Community-weighted mean trait values (CWMs), a common measure, are largely driven by the most common species and thus do not reflect community-wide trait–niche relationships per se. Alternatively, trait–niche relationships can be estimated across a larger group of species using hierarchical joint species distribution models (JSDMs), quantified by a parameter Γ. We investigated how inferences about trait–niche relationships are affected by the choice of metric. Using deadwood-dependent (saproxylic) beetles in fragmented Finnish forests, we followed a protocol for investigating trait–niche relationships by (1) identifying environmental filters (climate, forest age, and deadwood volume), (2) relating these to an ecological function (dispersal ability), and (3) identifying traits related to this function (wing morphology). We tested 18 hypothesized dispersal relationships using both CWM and Γ estimates across these environmental gradients. CWMs were more likely than Γ to show support for trait–niche relationships. Up to 13% of species' realized niches were explained by dispersal traits, but the directions of effects were consistent with fewer than 11%–39% of our 18 trait–niche hypotheses (depending on the metric used). This highlights the difficulty in connecting morphological traits and ecological functions in insects, despite the clear conceptual link between landscape connectivity and flight-related traits. Caution is thus warranted in hypothesis development, particularly where apparent trait–function links are less clear. Inferences differ when CWMs versus Γ estimates are used, necessitating the choice of a metric that reflects study questions. CWMs help explain the effects of environmental gradients on community trait composition, whereas the effects of traits on species' niches are better estimated using hierarchical JSDMs.

Keywords: beetles; phylogeny; morphology (biology); ecological niche; biotic communities; ecosystems (ecology)

Free keywords: Bayesian joint species distribution model; community-weighted mean trait values; deadwood; dispersal capacity; morphological traits; phylogeny; response trait; wing length

Contributing organizations

Ministry reporting: Yes

VIRTA submission year: 2023

JUFO rating: 1