The Caribbean archipelago is a region with an extremely complex geological history and an outstanding plant diversity with high levels of endemism. The aim of this study was to better understand the historical assembly and evolution of endemic seed plant genera in the Caribbean, by first determining divergence times of endemic genera to test whether the hypothesized Greater Antilles and Aves Ridge (GAARlandia) land bridge played a role in the archipelago colonization and second by testing South America as the main colonization source as expected by the position of landmasses and recent evidence of an asymmetrical biotic interchange. We reconstructed a dated molecular phylogenetic tree for 625 seed plants including 32 Caribbean endemic genera using Bayesian inference and ten calibrations. To estimate the geographic range of the ancestors of endemic genera, we performed a model selection between a null and two complex biogeographic models that included timeframes based on geological information, dispersal probabilities, and directionality among regions. Crown ages for endemic genera ranged from Early Eocene (53.1 Ma) to Late Pliocene (3.4 Ma). Confidence intervals for divergence times (crown and/or stem ages) of 22 endemic genera occurred within the GAARlandia time frame. Contrary to expectations, the Antilles appears as the main ancestral area for endemic seed plant genera and only five genera had a South American origin. In contrast to patterns shown for vertebrates and other organisms and based on our sampling, we conclude that GAARlandia did not act as a colonization route for plants between South America and the Antilles. Further studies on Caribbean plant dispersal at the species and population levels will be required to reveal finer‐scale biogeographic patterns and mechanisms.

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Background The extent and impact of evolutionary change occurring in natural populations in response to rapid anthropogenic impact is still poorly understood on the genome-wide level. Here, we explore the genetic structure, demographic history, population differentiation, and domestic introgression based on whole genome data of the endangered European wildcat in Germany, to assess potential genomic consequences of the species’ recent spread across human-dominated cultural landscapes. Results Reconstruction of demographic history and introgression rates based on 47 wildcat and 37 domestic cat genomes suggested late introgression between wild and domestic cat, coinciding with the introduction of domestic cat during the Roman period, but overall relatively low rates of hybridization and introgression from domestic cats. Main population divergence found between an eastern and central German wildcat clade was found to be of rather recent origin (200 y), and thus the likely consequence of anthropogenic persecution and resulting isolation in population refugia. We found similar effective population sizes and no substantial inbreeding across populations. Interestingly, highly differentiated genes between wild cat populations involved in the tryptophan-kynurenine-serotonin pathway were revealed, which plays a role in behavioral processes such as stress susceptibility and tolerance, suggesting that differential selection acted in the populations. Conclusions We found strong evidence for substantial recent anthropogenic impact on the genetic structure of European wildcats, including recent persecution-driven population divergence, as well as potential adaptation to human-dominate environments. In contrast, the relatively low levels of domestic introgression and inbreeding found in this study indicate a substantial level of “resistance” of this elusive species towards major anthropogenic impacts, such as the omnipresence of domestic cats as well as substantial habitat fragmentation. While those findings have strong implications for ongoing conservation strategies, we demand closer inspection of selective pressures acting on this and other wildlife species in anthropogenic environments.

Aim: The Progression Rule, that older lineages inhabit older islands and colonize newer ones as they emerge, has seldom been tested in the Caribbean due to its geological complexity. Here, we use the conifer genus Podocarpus to explore this hypothesis. We infer the evolutionary history, biogeography, and diversification rates of this genus under a hypothesis testing framework. Location: The Caribbean archipelago (Antilles). Taxon: Podocarpus (Podocarpaceae). Methods: We present the most comprehensive sampling for Caribbean Podocarpus to date in a Bayesian dated phylogenetic tree using a genotyping by sequencing DNA matrix of 67,589 bp. We inferred ancestral ranges and inter-island divergence patterns using several models available. We explored diversification rates associated with island colonization, and checked for diversification rate shifts in the phylogeny. Results: Caribbean Podocarpus is the result of colonization from the Andes during the Eocene to Oligocene (c. 45-31 Ma). Lesser Antillean species originated during the Oligocene from the Andes or the Greater Antilles, depending on the model of choice. Vicariance can explain the divergence of Cuban and Hispaniolan species, with subsequent dispersals into Jamaica. Despite the availability of new habitat opportunities, which might promote cladogenesis, insular Podocarpus did not show higher diversification rates than continental taxa. Main conclusions: The conditions for progression rule were not met because colonization of younger islands (Lesser Antilles) occurred from the continent, or because suitable habitat in the partially emerged younger islands was likely present at the time older islands (Greater Antilles) were colonized. An improved palaeogeographical knowledge of the Caribbean will allow testing this hypothesis in multiple lineages. Our finding that diversification rates did not increase with island colonization might be common in other Caribbean lineages. Genotyping by sequencing proved promising to reveal complex historical assembly processes of vicariance and dispersal at a fine phylogenetic scale.

This is an open access article under the terms of the Creat ive Commo ns Attri bution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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