Phylogeographic pattern of Rhizophora (Rhizophoraceae) reveals the importance of both vicariance and long-distance oceanic dispersal to modern mangrove distribution.

Background: Mangroves are key components of coastal ecosystems in tropical and subtropical regions worldwide. However, the patterns and mechanisms of modern distribution of mangroves are still not well understood. Historical vicariance and dispersal are two hypothetic biogeographic processes in shaping the patterns of present-day species distributions.

Expanded phylogenetic and dating analyses of the apples and their relatives (Pyreae, Rosaceae).

Despite previous efforts to elucidate relationships within the Pyreae (Rosaceae), relationships among the major sub-lineages, generic limits, and divergence times have remained uncertain. The present study greatly expands phylogenetic analyses of the Pyreae by using a combination of 11 chloroplast regions plus nuclear ribosomal ITS sequences from 486 individuals representing 331 species and 27 genera. Maximum likelihood and bayesian analyses generally support existing generic boundary, although Sorbus, as previously circumscribed, is clearly non-monophyletic.

Fine-scale comparisons of genetic variability in seed families of asexually and sexually reproducing Crataegus (hawthorn; Rosaceae).

The reproductive system is one of the key mechanisms that determine genetic diversity at different biological levels. However, few attempts have been made to assess the consequences of asexual reproduction by comparing genetic structure and fecundity of seed families in asexually and sexually reproducing individuals. We have examined two similar hawthorn species, Crataegus crus-galli and C.

Genomic markers reveal introgressive hybridization in the Indo-West Pacific mangroves: a case study.

Biodiversity of mangrove ecosystems is difficult to assess, at least partly due to lack of genetic verification of morphology-based documentation of species. Natural hybridization, on the one hand, plays an important role in evolution as a source of novel gene combinations and a mechanism of speciation. However, on the other hand, recurrent introgression allows gene flow between species and could reverse the process of genetic differentiation among populations required for speciation.

Reconstructing reticulation history in a phylogenetic framework and the potential of allopatric speciation driven by polyploidy in an agamic complex in Crataegus (Rosaceae).

Polyploidy plays a prominent role in the speciation process in plants. Many species are known to be part of agamic complexes comprising sexual diploids and more or less exclusively asexual polyploids. However, polyploid formation has been studied in very few cases, primarily because of the challenges in examining these cases phylogenetically.

Evidence for genetic association between East Asian and western North American Crataegus L. (Rosaceae) and rapid divergence of the eastern North American lineages based on multiple DNA sequences.

Phylogeographic relationships were constructed for 72 Old and New World Crataegus species using combinations of four chloroplast and up to five nuclear regions. Maximum parsimony, maximum likelihood, and Bayesian results yield consistent relationships among major lineages. The close associations of the East Asian and western North American species point toward ancient trans-Beringian migrations.

Population genetic structure of diploid sexual and polyploid apomictic hawthorns (Crataegus; Rosaceae) in the Pacific Northwest.

Polyploidy and gametophytic apomixis are two important and associated processes in plants. Many hawthorn species are polyploids and can reproduce both sexually and apomictically. However, the population genetic structure of these species is poorly understood.