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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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homologizer: Phylogenetic phasing of gene copies into polyploid subgenomes
Abstract Organisms such as allopolyploids and F1 hybrids contain multiple distinct subgenomes, each potentially with its own evolutionary history. These organisms present a challenge for multilocus phylogenetic inference and other analyses since it is not apparent which gene copies from different loci are from the same subgenome and thus share an evolutionary history.Here we introduce homologizer, a flexible Bayesian approach that uses a phylogenetic framework to infer the phasing of gene copies across loci into their respective subgenomes.Through the use of simulation tests, we demonstrate that homologizer is robust to a wide range of factors, such as incomplete lineage sorting and the phylogenetic informativeness of loci. Furthermore, we establish the utility of homologizer on real data, by analysing a multilocus dataset consisting of nine diploids and 19 tetraploids from the fern family Cystopteridaceae.Finally, we describe how homologizer may potentially be used beyond its core phasing functionality to identify non‐homologous sequences, such as hidden paralogs or contaminants.
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- PAR ID:
- 10401462
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Methods in Ecology and Evolution
- Volume:
- 14
- Issue:
- 5
- ISSN:
- 2041-210X
- Page Range / eLocation ID:
- p. 1230-1244
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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