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Abstract Copy number variation (CNV) is a major part of the genetic diversity segregating within populations, but remains poorly understood relative to single nucleotide variation. Here, we report on atRNAligase gene (Migut.N02091;RLG1a) exhibiting unprecedented, and fitness‐relevant,CNVwithin an annual population of the yellow monkeyflowerMimulus guttatus.RLG1a variation was associated with multiple traits in pooled population sequencing (PoolSeq) scans of phenotypic and phenological cohorts. Resequencing of inbred lines revealed intermediate‐frequency three‐copy variants ofRLG1a (trip+;5/35 = 14%), andtrip+lines exhibited elevatedRLG1a expression under multiple conditions.trip+carriers, in addition to being over‐represented in late‐flowering and large‐flowered PoolSeq populations, flowered later under stressful conditions in a greenhouse experiment (p < 0.05). In wild population samples, we discovered an additional rareRLG1a variant (high+) that carries 250–300 copies ofRLG1a totalling ~5.7 Mb (20–40% of a chromosome). In the progeny of ahigh+carrier, Mendelian segregation of diagnostic alleles andqPCR‐based copy counts indicate thathigh+is a single tandem array unlinked to the single‐copyRLG1a locus. In the wild,high+carriers had highest fitness in two particularly dry and/or hot years (2015 and 2017; bothp < 0.01), while single‐copy individuals were twice as fecund as eitherCNVtype in a lush year (2016:p < 0.005). Our results demonstrate fluctuating selection onCNVs affecting phenological traits in a wild population, suggest that planttRNAligases mediate stress‐responsive life‐history traits, and introduce a novel system for investigating the molecular mechanisms of gene amplification.
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A roadmap for exploring the thematic content of ecology journals
Abstract Ecologists—especially those new to the field—are tasked with finding relevant literature matching their research interests and deciding upon a suitable venue for the publication of their work. To provide a roadmap for early career researchers to identify journals aligned with their interests, we analyzed major research themes found across the top 30 ecology journals and three high‐impact multi‐disciplinary journals (Nature, PNAS,andScience), utilizing an automated content analysis (ACA) of 84,841 article abstracts, titles, and author keywords published over the last four decades. Journals clustered into 10 distinct groups based on 46 research themes identified byACA. We examined the frequency of ecological themes in each of these journal groups to identify the journals most associated with each theme. We found three themes (anthropogenic impacts, disease,andtraits) that occurred at a high frequency in the high‐impact multi‐disciplinary journal group containingNature, PNAS,andScience. Themes that increased in frequency over the last four decades, such asclimate change, traits, anthropogenic, andcellular biology, were found more often in journals with higher impact factors, indicating that emerging research themes in ecology will likely become of interest to a broader readership over time. Our study provides a thematic review as a potential roadmap for junior ecologists to browse and publish journal articles.
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- Award ID(s):
- 1638702
- PAR ID:
- 10460171
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 10
- Issue:
- 8
- ISSN:
- 2150-8925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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