論文 - 詳細
| RRC ID | 70077 |
|---|---|
| 著者 | Moraes AP, Engel TBJ, Forni-Martins ER, de Barros F, Felix LP, Cabral JS. |
| タイトル | Are chromosome number and genome size associated with habit and environmental niche variables? Insights from the Neotropical orchids. |
| ジャーナル | Ann Bot |
| Abstract |
BACKGROUND AND AIMS:The entangled relationship between chromosome number and genome size with species distribution has been the subject of study for almost a century but remains an open question due to previous ecological and phylogenetic knowledge constraints. To better address this subject, we used the clade Maxillariinae, a widely distributed and karyotypically known orchid group, as a model system to infer such relationships in a robust methodological framework. METHODS:Based on literature and new data, we gathered the chromosome number and genome size for 93 and 64 species, respectively. We built a phylogenetic hypothesis and assessed the best macroevolutionary model for both genomic traits. Additionally, we gathered ecological data (preferences for bioclimatic variables, elevation, and habit) used as explanatory variables in multivariate phylogenetic models explaining genomic traits. Finally, the impact of polyploidy was estimated by running the analyses with and without polyploids in the sample. KEY RESULTS:The association between genomic and ecological data varied depending on whether polyploids were considered or not. Without polyploids, chromosome number failed to present consistent associations with ecological variables. With polyploids, there was a tendency to waive epiphytism and colonise new habitats outside humid forests. The genome size showed association with ecological variables: without polyploids, genome upsize was associated with flexible habits, with higher elevation and with drier summers; with polyploids, genome size increase was associated with colonising drier environments. CONCLUSIONS:The chromosome number and genome size variations, essential but neglected traits in the ecological niche, are shaped in the Maxillariinae by both neutral and adaptive evolution. Both genomic traits are partially correlated to bioclimatic variables and elevation, even when controlling for phylogenetic constraints. While polyploidy was associated with shifts in the environmental niche, the genome size emerges as a central trait to orchid evolution by the association between small genome size with epiphytism, a key innovation to Neotropical orchid diversification. |
| 巻・号 | 130(1) |
| ページ | 11-25 |
| 公開日 | 2022-2-10 |
| DOI | 10.1093/aob/mcac021 |
| PII | 6526429 |
| PMID | 35143612 |
| PMC | PMC9295925 |
| MeSH | Chromosomes Genome Size Habits Orchidaceae* / genetics Phylogeny Polyploidy* |
| IF | 4.005 |
| リソース情報 | |
| GBIF | Ibaraki Nature Museum, Vascular Plants collection |