Multiple introductions and gene flow in subtropical South American populations of the fireweed, Senecio madagascariensis(Asteraceae).

Non-indigenous plants exhibit different attributes that make them aggressive competitors with indigenous plants and serious threats to biodiversity.Senecio madagascariensis (fireweed, Asteraceae), a native from southern Africa, is a strong competitor in agricultural activities and has toxic alkaloids that may result in high cattle mortality. In Brazil, this weed was collected for the first time in 1995 and has since spread quickly throughout the Pampas region.

Multilocus phylogeny reconstruction: new insights into the evolutionary history of the genus Petunia.

The phylogeny of Petunia species has been difficult to resolve, primarily due to the recent diversification of the genus. Several studies have included molecular data in phylogenetic reconstructions of this genus, but all of them have failed to include all taxa and/or analyzed few genetic markers. In the present study, we employed the most inclusive genetic and taxonomic datasets for the genus, aiming to reconstruct the evolutionary history of Petunia based on molecular phylogeny, biogeographic distribution, and character evolution.

Nuclear and plastid markers reveal the persistence of genetic identity: a new perspective on the evolutionary history of Petunia exserta.

Recently divergent species that can hybridize are ideal models for investigating the genetic exchanges that can occur while preserving the species boundaries. Petunia exserta is an endemic species from a very limited and specific area that grows exclusively in rocky shelters. These shaded spots are an inhospitable habitat for all other Petunia species, including the closely related and widely distributed species P.

A bayesian approach to genome/linguistic relationships in native South Americans.

The relationship between the evolution of genes and languages has been studied for over three decades. These studies rely on the assumption that languages, as many other cultural traits, evolve in a gene-like manner, accumulating heritable diversity through time and being subjected to evolutionary mechanisms of change. In the present work we used genetic data to evaluate South American linguistic classifications.

High rate of viral evolution in the capsid protein of porcine parvovirus.

In recent years, it has been shown that some parvoviruses exhibit high substitution rates, close to those of RNA viruses. In order to monitor and determine new mutations in porcine parvovirus (PPV), recent PPV field isolates from Austria, Brazil, Germany and Switzerland were sequenced and analysed. These samples, together with sequences retrieved from GenBank, were included in three datasets, consisting of the complete NS1 and VP1 genes and a partial VP1 gene.

Molecular phylogeny of Trichomonadidae family inferred from ITS-1, 5.8S rRNA and ITS-2 sequences.

The Trichomonads have been the subject of several molecular studies that reported some discrepancies both at the lower and higher taxonomic levels. The purpose of this study was to make an extensive phylogenetic analysis of the Trichomonadidae using ITS-1/5.8S/ITS-2 sequences, to better understand its phylogeny and the usefulness of this marker.