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Title: Functional trait evolution in Sphagnum peat mosses and its relationship to niche construction
Summary

Species in the genusSphagnumcreate, maintain, and dominate boreal peatlands through ‘extended phenotypes’ that allow these organisms to engineer peatland ecosystems and thereby impact global biogeochemical cycles. One such phenotype is the production of peat, or incompletely decomposed biomass, that accumulates when rates of growth exceed decomposition. Interspecific variation in peat production is thought to be responsible for the establishment and maintenance of ecological gradients such as the microtopographic hummock‐hollow gradient, along which sympatric species sort within communities.

This study investigated the mode and tempo of functional trait evolution across 15 species ofSphagnumusing data from the most extensive studies ofSphagnumfunctional traits to date and phylogenetic comparative methods.

We found evidence for phylogenetic conservatism of the niche descriptor height‐above‐water‐table and of traits related to growth, decay and litter quality. However, we failed to detect the influence of phylogeny on interspecific variation in other traits such as shoot density and suggest that environmental context can obscure phylogenetic signal. Trait correlations indicate possible adaptive syndromes that may relate to niche and its construction.

This study is the first to formally test the extent to which functional trait variation amongSphagnumspecies is a result of shared evolutionary history.

 
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Award ID(s):
1737899
NSF-PAR ID:
10461462
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
223
Issue:
2
ISSN:
0028-646X
Page Range / eLocation ID:
p. 939-949
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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