Corrigendum: Museomics Unveil the Phylogeny and Biogeography of the Neglected Juan Fernandez Archipelago Megalachne and Podophorus Endemic Grasses and Their Connection With Relict Pampean-Ventanian Fescues.
Ontology highlight
ABSTRACT:
SUBMITTER: Moreno-Aguilar MF
PROVIDER: S-EPMC8719599 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Oceanic islands constitute natural laboratories to study plant speciation and biogeographic patterns of island endemics. Juan Fernandez is a southern Pacific archipelago consisting of three small oceanic islands located 600-700 km west of the Chilean coastline. Exposed to current cold seasonal oceanic climate, these 5.8-1 Ma old islands harbor a remarkable endemic flora. All known Fernandezian endemic grass species belong to two genera, Megalachne and Podophorus, of uncertain taxonomic adscription. Classical and modern classifications have placed them either in Bromeae (Bromus), Duthieinae, Aveneae/Poeae, or Loliinae (fine-leaved Festuca); however, none of them have clarified their evolutionary relationships with respect to their closest Festuca relatives. Megalachne includes four species, which are endemic to Masatierra (Robinson Crusoe island) (M. berteroniana and M. robinsoniana) and to Masafuera (Alejandro Selkirk island) (M. masafuerana and M. dantonii). The monotypic Podophorus bromoides is a rare endemic species to Masatierra which is only known from its type locality and is currently considered extinct. We have used museomic approaches to uncover the challenging evolutionary history of these endemic grasses and to infer the divergence and dispersal patterns from their ancestors. Genome skimming data were produced from herbarium samples of M. berteroniana and M. masafuerana, and the 164 years old type specimen of P. bromoides, as well as for a collection of 33 species representing the main broad- and fine-leaved Loliinae lineages. Paired-end reads were successfully mapped to plastomes and nuclear ribosomal cistrons of reference Festuca species and used to reconstruct phylogenetic trees. Filtered ITS and trnTLF sequences from these genomes were further combined with our large Loliinae data sets for accurate biogeographic reconstruction. Nuclear and plastome data recovered a strongly supported fine-leaved Fernandezian clade where Podophorus was resolved as sister to Megalachne. Bayesian divergence dating and dispersal-extinction-cladogenesis range evolution analyses estimated the split of the Fernandezian clade from its ancestral southern American Pampas-Ventanian Loliinae lineage in the Miocene-Pliocene transition, following a long distance dispersal from the continent to the uplifted volcanic palaeo-island of Santa Clara-Masatierra. Consecutive Pliocene-Pleistocene splits and a Masatierra-to-Masafuera dispersal paved the way for in situ speciation of Podophorus and Megalachne taxa.
| S-EPMC7333454 | biostudies-literature
Project description:A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity. We investigate speciation in Drimys confertifolia, endemic to the two major islands of the Juan Fernández Archipelago, Chile, to determine genetic consequences of anagenesis, to examine relationships among populations of D. confertifolia and the continental species D. winteri and D. andina, and to test probable migration routes between the major islands. Population genetic analyses were conducted using AFLPs and nuclear microsatellites of 421 individuals from 42 populations from the Juan Fernández islands and the continent. Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor. The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape. Analysis of the probability of migration within the archipelago confirms colonization from the older island, Robinson Crusoe, to the younger island Alejandro Selkirk.
| S-EPMC4300435 | biostudies-literature
Project description:Knowledge about the spatial patterns and movements of crustaceans has gained importance since the creation of marine protected areas and the development of spatial management for benthic ecosystems. The Juan Fernández spiny lobster (Jasus frontalis) is an endemic marine species and most valuable resource that exhibits migratory dynamics in a highly spatially regulated fishery. To study movement patterns around Alexander Selkirk Island, a mark-recapture program was implemented in 2008, when approximately 7000 non-commercial (undersized) lobsters were tagged and followed for nearly 14 months. Using quantitative georeferenced data, this study revealed spatial structuring of Juan Fernández spiny lobster and tested hypotheses about alongshore and inshore-offshore movements. Eight clusters were identified around Alexander Selkirk Island, with moderate time-varying connectivity between them. Seasonal inshore-offshore movements were detected all around the island, but more conspicuously to the north. Average travelling distance was 1.2 km (1.7 sd). Our results confirmed that towards the end of austral spring males and females embark in a seasonal offshore migration to deeper waters, returning to shallower waters only during winter. These findings quantitatively consolidate the conceptual migratory model that local fishermen had already inferred for this resource from about a century of sustainable fishing.
| S-EPMC6059422 | biostudies-literature
Project description:Ten microsatellite markers were developed for Robinsonia (Asteraceae), a genus endemic to the Juan Fernández Archipelago, Chile. Polymorphisms of these markers were tested using one population each of R. evenia, R. gayana, and R. gracilis. The number of alleles for these markers ranged from 2 to 17 per locus, and expected heterozygosity ranged from 0 to 0.847 by population. A significant deviation from Hardy-Weinberg equilibrium was observed in zero to two markers in each population, and no significant linkage disequilibrium between markers was detected. The markers reported here would be useful for evolutionary studies and conservation strategies in Robinsonia.
| S-EPMC3579811 | biostudies-literature
Project description:The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.
| S-EPMC4703205 | biostudies-literature
Project description:Patterns in the Juan Fernandez fur seal (Arctophoca philippii philippii) faecal microbiome
| PRJEB43162 | ENA
Project description:The Juan Fernández Ridge (JFRE) is a vulnerable marine ecosystem (VME) located off the coast of central Chile formed by the Juan Fernández Archipelago and a group of seamounts. This ecosystem has unique biological and oceanographic features, characterized by: small geographical units, high degree of endemism with a high degree of connectivity within the system. Two fleets have historically operated in this system: a long term coastal artisanal fishery associated with the Islands, focused mainly on lobster, and a mainland based industrial demersal finfish fishery operating on the seamounts which is currently considered overexploited. The management of these fisheries has been based on a classical single-species approach to determine output controls (industrial fleet) and a mixed management system with formal and informal components (artisanal fleet). There has been growing interest in increasing the exploitation of fisheries, and modernization of the fishing fleet already operating in the JFRE. Under this scenario of increased levels of fishing exploitation and the high level of interrelation of species it might be necessary to understand the impact of these fisheries from a holistic perspective based on a ecosystem-based modeling approach. To address these challenges we developed an Atlantis end-to-end model was configured for this ecosystem. The implemented model has a high degree of skill in representing the observed trends and fluctuations of the JFRE. The model shows that the industrial fishing has a localized impact and the artisanal fisheries have a relatively low impact on the ecosystem, mainly via the lobster fishery. The model indicates that the depletion of large sized lobster has leads to an increase in the population of sea urchins. Although this increase is not sufficient, as yet, to cause substantial flow-on effects to other groups, caution is advised in case extra pressure leads the ecosystem towards a regime shift.
| S-EPMC6386342 | biostudies-literature
Project description:Dendroseris D. Don comprises 11 species endemic to the Juan Fernández islands in Chile. They demonstrate spectacular and unusual growth forms of rosette trees with extremely variable morphology and occupy wide ecological ranges on the islands. These unique plants are now highly threatened with extinction with very small population sizes, typically consisting of 10 or fewer individuals in wild. Despite morphological and ecological divergence among species of Dendroseris, their monophyly has been supported in previous studies, but with little resolution among subgeneric groups. We assembled seven complete plastome sequences from seven species of Dendroseris, including representatives from three subgenera, and carried out comparative phylogenomic analyses. The plastomes are highly conserved in gene content and order, with size ranging from 152,199 to 152,619 bp and containing 130 genes (87 coding genes, 6 rRNA genes, and 37 tRNA genes). Plastid phylogenomic analyses based on both the complete plastome sequences and 81 concatenated coding genes only show Dendroseris nested within Sonchus sensu lato, and also that inter-subgeneric relationships are fully resolved. Subg. Phoenicoseris is resolved as sister to the remaining species of the genus and a sister relationship between the two subgenera Dendroseris and Rea. Ten mutation hotspots from LSC and SSC regions and variable SSRs are identified as potential chloroplast markers for future phylogenetic and phylogeographic studies of Sonchus and related groups.
| S-EPMC7674203 | biostudies-literature
Project description:Erigeron represents the third largest genus on the Juan Fernández Islands, with six endemic species, five of which occur exclusively on the younger Alejandro Selkirk Island with one species on both islands. While its continental sister species is unknown, Erigeron on the Juan Fernández Islands appears to be monophyletic and most likely evolved from South American progenitor species. We characterized the complete chloroplast genomes of five Erigeron species, including accessions of E. fernandezia and one each from Alejandro Selkirk and Robinson Crusoe Islands, with the purposes of elucidating molecular evolution and phylogenetic relationships. We found highly conserved chloroplast genomes in size, gene order and contents, and further identified several mutation hotspot regions. In addition, we found two positively selected chloroplast genes (ccsA and ndhF) among species in the islands. The complete plastome sequences confirmed the monophyly of Erigeron in the islands and corroborated previous phylogenetic relationships among species. New findings in the current study include (1) two major lineages, E. turricola-E. luteoviridis and E. fernandezia-E. ingae-E. rupicola, (2) the non-monophyly of E. fernandezia occurring on the two islands, and (3) the non-monophyly of the alpine species E. ingae complex.
| S-EPMC10935083 | biostudies-literature
Project description:This corrects the article DOI: 10.1038/sdata.2017.37.
| S-EPMC5496469 | biostudies-other