The Himalayan mountain range is one of the most species-rich areas in the world, harboring about 8% of the world's bird species.In this study, we compare the relative importance of immigration versus in situ speciation to the build-up of the Himalayan avifauna, by evaluating the biogeographic history of the Phylloscopus/Seicercus warblers, a speciose clade that is well represented in Himalayan forests. We use a comprehensive, multigene phylogeny in conjunction with dispersal-vicariance analysis to discern patterns of speciation and dispersal within this clade. The results indicate that virtually no speciation has occurred within the Himalayas. Instead, several speciation events are attributed to dispersal into the Himalayas followed by vicariance between the Himalayas and China/Southeast Asia. Most, perhaps all, of these events appear to be pre-Pleistocene. The apparent lack of speciation within the Himalayas stands in contrast to the mountain-driven Pleistocene speciation suggested for the Andes and the East African mountains.
The protection, preservation and restoration of aquatic ecosystems and their functions are of global importance. For European states it became legally binding mainly through the EU-Water Framework Directive (WFD). In order to assess the ecological status of a given water body, aquatic biodiversity data are obtained and compared to a reference water body. The quantified mismatch obtained determines the extent of potential management actions. The current approach to biodiversity assessment is based on morpho-taxonomy. This approach has many drawbacks such as being time consuming, limited in temporal and spatial resolution, and error-prone due to the varying individual taxonomic expertise of the analysts. Novel genomic tools can overcome many of the aforementioned problems and could complement or even replace traditional bioassessment. Yet, a plethora of approaches are independently developed in different institutions, thereby hampering any concerted routine application. The goal of this Action is to nucleate a group of researchers across disciplines with the task to identify gold-standard genomic tools and novel ecogenomic indices for routine application in biodiversity assessments of European fresh-and marine water bodies. Furthermore, DNAqua-Net will provide a platform for training of the next generation of European researchers preparing them for the new technologies. Jointly with water managers, politicians, and other stakeholders, the group will develop a
BackgroundIt has been suggested that statistical parsimony network analysis could be used to get an indication of species represented in a set of nucleotide data, and the approach has been used to discuss species boundaries in some taxa.Methodology/Principal FindingsBased on 635 base pairs of the mitochondrial protein-coding gene cytochrome c oxidase I (COI), we analyzed 152 nemertean specimens using statistical parsimony network analysis with the connection probability set to 95%. The analysis revealed 15 distinct networks together with seven singletons. Statistical parsimony yielded three networks supporting the species status of Cephalothrix rufifrons, C. major and C. spiralis as they currently have been delineated by morphological characters and geographical location. Many other networks contained haplotypes from nearby geographical locations. Cladistic structure by maximum likelihood analysis overall supported the network analysis, but indicated a false positive result where subnetworks should have been connected into one network/species. This probably is caused by undersampling of the intraspecific haplotype diversity.Conclusions/SignificanceStatistical parsimony network analysis provides a rapid and useful tool for detecting possible undescribed/cryptic species among cephalotrichid nemerteans based on COI gene. It should be combined with phylogenetic analysis to get indications of false positive results, i.e., subnetworks that would have been connected with more extensive haplotype sampling.
Annelids of the genus Ophryotrocha are small opportunistic worms commonly found in polluted and nutrient-rich habitats such as harbors. Within this small group of about 40 described taxa a large variety of reproductive strategies are found, ranging from gonochoristic broadcast spawners to sequential hermaphroditic brooders. Many of the species have a short generation time and are easily maintained as laboratory cultures. Thus they have become a popular system for exploring a variety of biological questions including developmental genetics, ethology, and sexual selection. Despite considerable behavioral, reproductive, and karyological studies, a phylogenetic framework is lacking because most taxa are morphologically similar. In this study we use 16S mitochondrial gene sequence data to infer the phylogeny of Ophryotrocha strains commonly used in the laboratory. The resulting mtDNA topologies are generally well resolved and support a genetic split between hermaphroditic and gonochoristic species. Although the ancestral state could not be unambiguously identified, a change in reproductive strategy (i.e., hermaphroditism and gonochorism) occurred once within Ophryotrocha. Additionally, we show that sequential hermaphroditism evolved from a simultaneous hermaphroditic ancestor, and that characters previously used in phylogenetic reconstruction (i.e., jaw morphology and shape of egg mass) are homoplasic within the group.
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