Chromosomal evolution, environmental heterogeneity, and migration drive spatial patterns of species richness in Calochortus (Liliaceae)

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(10)

Published: Feb. 23, 2024

We used nuclear genomic data and statistical models to evaluate the ecological evolutionary processes shaping spatial variation in species richness Calochortus (Liliaceae, 74 spp.). occupies diverse habitats western United States Mexico has a center of diversity California Floristic Province, marked by multiple orogenies, winter rainfall, highly divergent climates substrates (including serpentine). sequences 294 low-copy loci produce time-calibrated phylogeny, estimate historical biogeography, test hypotheses regarding drivers present-day patterns number. Speciation coexistence require reproductive isolation divergence, so we examined roles chromosome number, environmental heterogeneity, migration local richness. Six major clades—inhabiting different geographic/climatic areas, often base numbers (n = 6 10)—began diverging from each other ~10.3 Mya. As predicted, number increased significantly with heterogeneity elevation, soil characteristics, serpentine presence. Species is greatest Transverse/Peninsular Ranges where clades overlap, topographic complexity provides conditions over short distances, several physiographic provinces meet allowing immigration clades. Recently diverged sister-species pairs generally have peri-patric distributions, maximum geographic overlap between increases first million years since suggesting that chromosomal evolution, genetic divergence leading gametic or hybrid inviability/sterility, and/or small scales may permit co-occurrence.

Language: Английский

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Phylogenomics of the tetraploid Hawaiian lobeliads: Implications for their origin, dispersal history, and adaptive radiation

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(19)

Published: May 5, 2025

Hawaiian lobeliads exhibit extensive adaptive radiations and are considered the largest plant clade (143 species) endemic to any oceanic archipelago. Rapid insular prone reticulate evolution, yet detecting hybridization is often limited by inadequate sampling of taxa or independent loci. We analyzed 633 nuclear loci (including tetraploid duplications) whole plastomes for 89% extant species derive phylogenies lobeliads. Nuclear data provide strong support nine major clades in both likelihood ASTRAL analyses. All genera/sections monophyletic except Clermontia Cyanea . plastome conflict on short, deep branches; tree resolves a fleshy-fruited Clermontia/Cyanea-Brighamia/Delissea , sister Polynesian Sclerotheca with capsular-fruited clade. Incomplete lineage sorting rapid radiation starting 8.5–11.3 Ma sufficient explain uncertainty cytonuclear discordance along backbone. Sequence reticulation within especially identify 42 interisland dispersal events: accord strict progression rule, involving movement next younger island hotspot chain, consistent theory. Plastid overestimate such events 17%. have undergone parallel elevational distribution flower length all islands, multiple founders some differences. lobeliad diversification was driven an early intergeneric divergence habitat, followed ecological speciation Clermontia/Cyanea combined widespread single-island endemism, frequent dispersal, occasional hybridization.

Language: Английский

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Convergent Evolution, Adaptive Radiation, and Species Diversification in Flowering Plants

Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Language: Английский

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