Phylogenomics reveals the slow- burning fuse of diatom evolution

• 成果类型: Article
• 署名作者: Alverson, Andrew J.; Roberts, Wade R.; Ruck, Elizabeth C.; Nakov, Teofil; Ashworth, Matthew P.; Brylka, Karolina; Downey, Kala M.; Kociolek, J. Patrick; Parks, Matthew; Pinseel, Eveline; Theriot, Edward C.; Tye, Simon P.; Witkowski, Andrzej; Beaulieu, Jeremy M.; Wickett, Norman J.
• 署名单位: University of Arkansas System; University of Arkansas Fayetteville; Universidad Costa Rica; University of Texas System; University of Texas Austin; Lund University; University of Colorado System; University of Colorado Boulder; University of Central Oklahoma; Ghent University; University of Texas System; University of Texas Austin; University of Szczecin; University of Vienna
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-15263
• DOI: 10.1073/pnas.2500153122
• 发表日期: 2025-06-03
• 关键词: inordinate fondness; diversity; number; bacillariophyta; insights; genes; shape; ACID

摘要

Evolution is often uneven in its pace and outcomes, with long periods of stasis interrupted by abrupt increases in morphological and ecological disparity. With thousands of gene histories, phylogenomics can uncover the genomic signatures of these broad macroevolutionary trends. Diatoms are a species- rich lineage of microeukaryotes that contribute greatly to the global cycling of carbon, oxygen, and silica, which they use to build elaborately structured cell walls. We combined fossil information with newly sequenced transcriptomes from 181 diverse diatom species to reconstruct the pattern, timing, and genomic context of major evolutionary transitions. Diatoms originated 270 Mya, and after >100 My of relative stasis in morphology and ecology, a radiation near the characteristic of modern diatoms. This transition was marked by a genome duplication and high levels of gene tree discordance. However, short generation times increase the probability of coalescence between speciation events, minimizing the impacts of incomplete lineage sorting and implicating sequence saturation and gene tree error as the associated with the evolution of novel traits and ecological transitions. The first 100 My of diatom evolution was a slow- burning fuse that led to a burst of innovations in ecology, morphology, and life history that are hallmarks of contemporary diatom assemblages.