Phylogenomic structure and speciation in an emerging model: the Sphagnum magellanicum complex (Bryophyta)
Phylogenomic structure and speciation in an emerging model: the Sphagnum magellanicum complex (Bryophyta)
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DOI：
10.1111/nph.18429
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发表时间：
2022-08-30
期刊：
影响因子：
9.4
通讯作者：
Hicks, Karen A.
中科院分区：
文献类型：
--
作者：
Shaw, A. Jonathan;Piatkowski, Bryan;Hicks, Karen A.
Magellanicum是两个泥炭藓物种之一，其参考质量基因组存在，以促进生态基因组学研究。基于来自48个样品的重测序数据和基于187个样品的RADseq分析进行系统发育和比较基因组分析。我们在此报道，有四个分支/种内的S。magellanicum复合体的参考基因组，并且参考基因组属于Sphagnumdivinum。这些物种表现出数万（RADseq）到数百万（重测序）的固定核苷酸差异。然而，有两个物种被非正式地称为S。diabolicum和S. magni，因为它们还没有被正式描述，仅通过100（RADseq）到1000（重测序）的差异来区分。使用D-统计量和f（4）比率证明了复合体中物种间的渐渗。一个生态学上重要的功能性状，组织分解性，是泥炭（碳）积累的基础，在S。magellanicum复合体，尽管先前的研究表明许多密切相关的泥炭藓物种在分解/碳封存方面存在差异。系统发育分辨率和更准确的物种划分在S。magellanicum复合体的发现大大增加了该类群在更广泛地研究气候适应和生态进化的早期进化阶段中的价值。
Sphagnum magellanicum is one of two Sphagnum species for which a reference-quality genome exists to facilitate research in ecological genomics. Phylogenetic and comparative genomic analyses were conducted based on resequencing data from 48 samples and RADseq analyses based on 187 samples. We report herein that there are four clades/species within the S. magellanicum complex in eastern North America and that the reference genome belongs to Sphagnum divinum. The species exhibit tens of thousands (RADseq) to millions (resequencing) of fixed nucleotide differences. Two species, however, referred to informally as S. diabolicum and S. magni because they have not been formally described, are differentiated by only 100 (RADseq) to 1000 (resequencing) of differences. Introgression among species in the complex is demonstrated using D-statistics and f(4) ratios. One ecologically important functional trait, tissue decomposability, which underlies peat (carbon) accumulation, does not differ between segregates in the S. magellanicum complex, although previous research showed that many closely related Sphagnum species have evolved differences in decomposability/carbon sequestration. Phylogenetic resolution and more accurate species delimitation in the S. magellanicum complex substantially increase the value of this group for studying the early evolutionary stages of climate adaptation and ecological evolution more broadly.