Repeated shifts out of tropical climates preceded by whole genome duplication.

While flowering plants have diversified in virtually every terrestrial clime, climate constrains the distribution of individual lineages. Overcoming climatic constraints may be associated with diverse evolutionary phenomena including whole genome duplication (WGD), gene-tree conflict, and life-history changes. Climatic shifts may also have facilitated increases in flowering plant diversification rates.

The phylogeny and global biogeography of Primulaceae based on high-throughput DNA sequence data.

The angiosperm family Primulaceae is morphologically diverse and distributed nearly worldwide. However, phylogenetic uncertainty has obstructed the identification of major morphological and biogeographic transitions within the clade. We used target capture sequencing with the Angiosperms353 probes, taxon-sampling encompassing nearly all genera of the family, tree-based sequence curation, and multiple phylogenetic approaches to investigate the major clades of Primulaceae and their relationship to other Ericales.

Admixture may be extensive among hyperdominant Amazon rainforest tree species.

Admixture is a mechanism by which species of long-lived plants may acquire novel alleles. However, the potential role of admixture in the origin and maintenance of tropical plant diversity is unclear. We ask whether admixture occurs in an ecologically important clade of Eschweilera (Parvifolia clade, Lecythidaceae), which includes some of the most widespread and abundant tree species in Amazonian forests.

By Animal, Water, or Wind: Can Dispersal Mode Predict Genetic Connectivity in Riverine Plant Species?

Seed dispersal is crucial to gene flow among plant populations. Although the effects of geographic distance and barriers to gene flow are well studied in many systems, it is unclear how seed dispersal mediates gene flow in conjunction with interacting effects of geographic distance and barriers. To test whether distinct seed dispersal modes (i.

A Biogeographic Barrier Test Reveals a Strong Genetic Structure for a Canopy-Emergent Amazon Tree Species.

Wallace's (1854) Riverine Barrier hypothesis is one of the earliest explanations for Amazon biotic diversification. Despite the importance of this hypothesis for explaining speciation in some animal groups, it has not been studied extensively for plant species. In this study we use a prominent Amazon tree, Buchenavia oxycarpa (Mart.

Genomic evidence of survival near ice sheet margins for some, but not all, North American trees.

Temperate species experienced dramatic range reductions during the Last Glacial Maximum, yet refugial populations from which modern populations are descended have never been precisely located. Climate-based models identify only broad areas of potential habitat, traditional phylogeographic studies provide poor spatial resolution, and pollen records for temperate forest communities are difficult to interpret and do not provide species-level taxonomic resolution. Here we harness signals of range expansion from large genomic datasets, using a simulation-based framework to infer the precise latitude and longitude of glacial refugia in two widespread, codistributed hickories ( spp.

Target sequence capture in the Brazil nut family (Lecythidaceae): Marker selection and in silico capture from genome skimming data.

Reconstructing species trees from multi-loci datasets is becoming a standard practice in phylogenetics. Nevertheless, access to high-throughput sequencing may be costly, especially with studies of many samples. The potential high cost makes a priori assessments desirable in order to make informed decisions about sequencing.

Scale and strength oak-mesophyte interactions in a transitional oak-hickory forest.

Forests in eastern North America are undergoing rapid compositional changes as they experience novel climate, disturbance, and pest conditions. One striking pattern is the replacement of canopy oaks spp.) by mesic, fire-sensitive, shade-tolerant species like red maple .

Tangled banks: A landscape genomic evaluation of Wallace's Riverine barrier hypothesis for three Amazon plant species.

Wallace's Riverine Barrier hypothesis is one of the earliest biogeographic explanations for Amazon speciation, but it has rarely been tested in plants. In this study, we used three woody Amazonian plant species to evaluate Wallace's Hypothesis using tools of landscape genomics. We generated unlinked single-nucleotide polymorphism (SNP) data from the nuclear genomes of 234 individuals (78 for each plant species) across 13 sampling sites along the Rio Branco, Brazil, for Amphirrhox longifolia (8,075 SNPs), Psychotria lupulina (9,501 SNPs) and Passiflora spinosa (14,536 SNPs).

Complete plastome sequences from and 23 related species yield informative markers for Lecythidaceae.

Premise Of The Study: The tropical tree family Lecythidaceae has enormous ecological and economic importance in the Amazon basin. Lecythidaceae species can be difficult to identify without molecular data, however, and phylogenetic relationships within and among the most diverse genera are poorly resolved.

Methods: To develop informative genetic markers for Lecythidaceae, we used genome skimming to de novo assemble the full plastome of the Brazil nut tree () and 23 other Lecythidaceae species.

Comment on "Persistent effects of pre-Columbian plant domestication on Amazonian forest composition".

Levis (Research Articles, 3 March 2017, p. 925) concluded that pre-Columbian tree domestication has shaped present-day Amazonian forest composition. The study, however, downplays five centuries of human influence following European arrival to the Americas.

Altitudinal gradients, biogeographic history and microhabitat adaptation affect fine-scale spatial genetic structure in African and Neotropical populations of an ancient tropical tree species.

The analysis of fine-scale spatial genetic structure (FSGS) within populations can provide insights into eco-evolutionary processes. Restricted dispersal and locally occurring genetic drift are the primary causes for FSGS at equilibrium, as described in the isolation by distance (IBD) model. Beyond IBD expectations, spatial, environmental or historical factors can affect FSGS.

Wide but not impermeable: Testing the riverine barrier hypothesis for an Amazonian plant species.

Wallace's riverine barrier hypothesis postulates that large rivers, such as the Amazon and its tributaries, reduce or prevent gene flow between populations on opposite banks, leading to allopatry and areas of species endemism occupying interfluvial regions. Several studies have shown that two major tributaries, Rio Branco and Rio Negro, are important barriers to gene flow for birds, amphibians and primates. No botanical studies have considered the potential role of the Rio Branco as a barrier, while a single botanical study has evaluated the Rio Negro as a barrier.

Minimum sample sizes for population genomics: an empirical study from an Amazonian plant species.

High-throughput DNA sequencing facilitates the analysis of large portions of the genome in nonmodel organisms, ensuring high accuracy of population genetic parameters. However, empirical studies evaluating the appropriate sample size for these kinds of studies are still scarce. In this study, we use double-digest restriction-associated DNA sequencing (ddRADseq) to recover thousands of single nucleotide polymorphisms (SNPs) for two physically isolated populations of Amphirrhox longifolia (Violaceae), a nonmodel plant species for which no reference genome is available.

Impacts of biogeographic history and marginal population genetics on species range limits: a case study of Liriodendron chinense.

Species ranges are influenced by past climate oscillations, geographical constraints, and adaptive potential to colonize novel habitats at range limits. This study used Liriodendron chinense, an important temperate Asian tree species, as a model system to evaluate the roles of biogeographic history and marginal population genetics in determining range limits. We examined the demographic history and genetic diversity of 29 L.

Spatial Scales of Genetic Structure in Free-Standing and Strangler Figs (Ficus, Moraceae) Inhabiting Neotropical Forests.

Wind-borne pollinating wasps (Agaonidae) can transport fig (Ficus sp., Moraceae) pollen over enormous distances (> 100 km). Because of their extensive breeding areas, Neotropical figs are expected to exhibit weak patterns of genetic structure at local and regional scales.

Polymorphic microsatellite markers for a wind-dispersed tropical tree species, Triplaris cumingiana (Polygonaceae).

Premise Of The Study: Novel microsatellite markers were characterized in the wind-dispersed and dioecious neotropical tree Triplaris cumingiana (Polygonaceae) for use in understanding the ecological processes and genetic impacts of pollen- and seed-mediated gene flow in tropical forests. •

Methods And Results: Sixty-two microsatellite primer pairs were screened, from which 12 markers showing five or more alleles per locus (range 5-17) were tested on 47 individuals. Observed and expected heterozygosities averaged 0.

Exon-primed intron-crossing (EPIC) markers for evolutionary studies of Ficus and other taxa in the fig family (Moraceae).

Premise Of The Study: The genus Ficus (fig trees) comprises ca. 750 species of trees, vines, and stranglers found in tropical forests throughout the world. Fig trees are keystone species in many tropical forests, and their relationship with host-specific wasp pollinators has received much attention, although many questions remain unresolved regarding the levels of host specificity, cospeciation, and the role of hybridization in fig and wasp speciation.

The effects of read length, quality and quantity on microsatellite discovery and primer development: from Illumina to PacBio.

The advent of next-generation sequencing (NGS) technologies has transformed the way microsatellites are isolated for ecological and evolutionary investigations. Recent attempts to employ NGS for microsatellite discovery have used the 454, Illumina, and Ion Torrent platforms, but other methods including single-molecule real-time DNA sequencing (Pacific Biosciences or PacBio) remain viable alternatives. We outline a workflow from sequence quality control to microsatellite marker validation in three plant species using PacBio circular consensus sequencing (CCS).

Fine-scale niche structure of Neotropical forests reflects a legacy of the Great American Biotic Interchange.

The tendency of species to retain their ancestral niches may link processes that determine community assembly with biogeographic histories that span geological time scales. Biogeographic history is likely to have had a particularly strong impact on Neotropical forests because of the influence of the Great American Biotic Interchange, which followed emergence of a land connection between North and South America ~3 Ma. Here we examine the community structure, ancestral niches and ancestral distributions of the related, hyperdiverse woody plant genera Psychotria and Palicourea (Rubiaceae) in Panama.

Polymorphic microsatellite loci for Virola sebifera (Myristicaceae) derived from shotgun 454 pyrosequencing.

Premise Of The Study: Polymorphic microsatellite loci were characterized in the dioecious neotropical rainforest tree Virola sebifera. The markers will be used to study ecological and genetic impacts of hunting and landscape change in this vertebrate-dispersed, insect-pollinated tree species.

Methods And Results: Simple sequence repeat (SSR) markers were screened from genomic libraries of South American V.

Neogene origins and implied warmth tolerance of Amazon tree species.

Tropical rain forest has been a persistent feature in South America for at least 55 million years. The future of the contemporary Amazon forest is uncertain, however, as the region is entering conditions with no past analogue, combining rapidly increasing air temperatures, high atmospheric carbon dioxide concentrations, possible extreme droughts, and extensive removal and modification by humans. Given the long-term Cenozoic cooling trend, it is unknown whether Amazon forests can tolerate air temperature increases, with suggestions that lowland forests lack warm-adapted taxa, leading to inevitable species losses.

Anonymous and EST-based microsatellite DNA markers that transfer broadly across the fig tree genus (Ficus, Moraceae).

Premise Of The Study: We developed a set of microsatellite markers for broad utility across the species-rich pantropical tree genus Ficus (fig trees). The markers were developed to study population structure, hybridization, and gene flow in neotropical species.

Methods And Results: We developed seven novel primer sets from expressed sequence tag (EST) libraries of F.