1) Multigenic and phylogenomic approaches to the origin and diversification of the bilaterian superclade Lophotrochozoa

Constructing robust phylogenies is central to understand the origin and radiation of any animal clade. We focus in the superclade Lophotrochozoa, an asemblage of 15 bilaterian phyla ranging from the well-known annelids, molluscs and platyhelminthes to a bunch of minor lesser-known phyla. After a decade of intensive gene sequencing (namely the 18S ribosomal gene), the origin, radiation and relationships of lophotrochozoan phyla are still very poorly known. Prominent among them is the unsettled position of the Platyhelminthes (flatworms), Gastrotricha, Gnathostomulida and Xenoturbella.

We follow a dual approach: 1) to sequence genes known to be good phylogenetic markers (e.g. 18S and 28S rDNA, myosin II, ATPase, tropomyosin, etc,...) using a taxon wide sampling, and 2) a phylogenomic approach based on EST collections from the basalmost taxa of each phylum. Various tree reconstruction methods are used. Using both approaches some robust groups of phyla are already emerging and morphological synapomorphies being tested.


Staff
Prof. Jaume Baguñà
Dr. Marta Riutort


Ph.D.students
Jordi Paps


Collaborators
Dr. Carles Ribera (Dpt. Biologia Animal, Universitat de Barcelona)
Dr. Gonzalo Giribet (Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MS, USA)
Dr. Ulf Jondelius (Dept. of Systematic Zoology, Univ. of Uppsala, Uppsala, Suècia)
Dr. Mark. Q. Martindale (Kewalo Marine Lab, Univ. of Hawaii, Honolulu, HI, USA)
Dr. Hervé Philippe (Dpt. de Biochimie, Univ. Montréal, Montréal, Quebec, Canada)




2) Molecular taxonomy and phylogeography of freshwater and land planarians

Freshwater and land planarians (Platyhelminthes, Tricladida) have characteristics (as low dispersive capacity, high sensibility to environment changes,…) that make of them good models to be used in biogeographical analyses and as biodiversity indicators. Using molecular data based technologies we are testing whether the asexual (fissiparous) forms of the freshwater genera Dugesia and Schmidtea in the Mediterranean, geographically more widespread than their sexual counterparts, have an ancient or a recent origin. First, we are establishing the phylogenetic relationships among the different species and populations of both genera, we will correlate them to their geographic distribution and try to find out the events that explain it; second, we compare its intrapopulational genetic variability. From it, we hope to unravel when and how asexual forms originated and why they are more widespread.

In the other hand, we have started an analysis of the presence of land planarians in the Ibeian Peninsula. A very preliminary study indicates that at least eleven species could be present. Now, a wide sampling is being made through all the Peninsula, from the data collected we expect to be able to determine how many species are present, basing both in morphological and molecular data, and their distribution. Basing on the genetic data some poblational parameters will be studied in order to understand the factors affecting this distribution and generating the high diversity found.


Staff
Dr. Marta Riutort
Prof. Jaume Baguñà
Dr. Eduardo Mateos (Dpt. Biologia Animal, Universitat de Barcelona)


PhD students
Eva Lázaro
Marta Álvarez



Collaborators
Dr. Ronald Sluys (Zoological Museum, Amsterdam University, The Nederlands)
Dr. Maria Pala, Dr. Salvatore Cassu (Università di Sassari, Sardinia, Italy)
Dr. Halim Harrath (University Tunis-el Manar, Tunisia)
Dr. Leon Blaustein (University of Haifa, Israel)





3) Molecular phylogeography of land planarians in the Brasilian Atlantic Forest. Implications for Biodiversity conservation

Land planarians have been selected to analyze the poblational fragmentation in the invertebrate communities in the Atlantic Forest, highly destroyed by human activites (less than 4% remains). In three species of this group DNA variability will be compared within the species and the populations (phylogeographic analyses and based on coalescent methods), and among species (phylogenetic analysis). This information will allow to determine, among other things, if populations are genetically structured and correlate this pattern with the presence of ecological, geographical barriers or with human activities.

Staff
Dr. Marta Riutort
Dr. Julio Rozas


PhD students
Marta Álvarez


Collaborators
Dr. Fernando Carbayo (Universidade de São Paulo, Brazil)
Dr. Fernando de-Luna-Marques (Universidade de São Paulo, Brazil)
Dr. Diogo Meyer (Universidade de São Paulo, Brazil)