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DR. MARCIAL ESCUDERO, POSTDOCTORAL MARIE CURIE IO-FELLOW IN JORDANO'S GROUP AT DOÑANA BIOLOGICAL STATION.

CURRENT PROJECT: HOLOCHROMEVOL.

EMAIL: AMESCLIR@GMAIL.COM

 

    My research interest is mainly focused in the evolution and diversification of flowering plants with special emphasis in genus Carex (Cyperaceae). Interestingly, with approximately 2,000 species worldwide, Carex is one of the largest angiosperm genera in the world. Our research aims to disentangle the causes behind this remarkable species richness. In order to unravel the evolutionary and diversification patterns of this genus, my colleagues and I perform studies of molecular phylogenetics and biogeographics, phylogeographics, cytogenetics, herbarium study, phylogenetic comparative analyses...  to study geographic (high long-distance dispersal ability), ecological (high habitat disparity) and chromosomal (rapid evolution of its holocentric chromosomes; 2n = 12 - 124) speciation in Carex.

I welcome collaborations with researchers at the undergraduate, graduate or post graduate level in ongoing projects or developing new projects. Please email me if you have questions.

Follow me in the networks:



http://scholar.google.es/citations?user=NIVWYBUAAAAJ&hl=es

https://twitter.com/MEscudero_Carex



LAST NEWS!!!!!

*DECEMBER-12-2014 

NEW ACCEPTED PUBLICATION ABOUT THE RELATIONSHIP BETWEEN CHROMOSOME NUMBER AND GENOME SIZE IN ORGANISMS WITH HOLOCENTRIC CHROMOSOMES.

ABSTRACT:

Premise of the study: In organisms with holocentric chromosomes like Carex species, chromosome number evolution has been hypothesized to be a result of fission, fusion and/or translocation events. Negative, positive or the absence of correlations have been found between chromosome number and genome size in Carex. Methods: Using the inferred diploid chromosome number and 80 genome size measurements from 26 individuals and 20 populations of Carex gr. laevigata, we have tested the null hypothesis of chromosome number evolution by duplication and deletion of whole chromosomes. Results: Our results show a significant positive correlation between genome size and chromosome number, but the slope of such correlation supports the hypothesis of proliferation and removal of repetitive DNA fragments to explain genome size variation rather than duplication and deletion of whole chromosomes. Conclusions: Our results refine the theory of the holokinetic drive: this mechanism is proposed to facilitate repetitive DNA removal (or any segmental deletion) when smaller homologous chromosomes are preferentially inherited or repetitive DNA proliferation (or any segmental duplication) when larger homologs are preferred. This study sheds light on how karyotype evolution plays an important role in the diversification of the species of the genus Carex.

MARCIAL ESCUDERO, ENRIQUE MAGUILLA, JOÃO LOUREIRO, MARIANA CASTRO, SILVIA CASTRO & MODESTO LUCEÑO. IN PRESS. GENOME SIZE STABILITY DESPITE HIGH CHROMOSOME NUMBER VARIATION IN CAREX GR. LAEVIGATA. AMERICAN JOURNAL OF BOTANY, 102, 233-238. LINK. PDF.

 

* NOVEMBER - 17 - 2014
LAST WEEK THE INTERNATIONAL CONFERENCE MODERN PHYLOGENETIC COMPARATIVE METHODS WAS CELEBRATED IN SEVILLA (NOVEMBER 11-15 2014).
The meeting was very successful and fulfilled the expectations.
Visit the WEBSITE. Photos are also available HERE.

* OCTOBER - 31 - 2014
NEW POSTDOCTORAL POSITION.
Today has been published the formal resolution for a two years postdoctoral position that I will enjoy at the University of Seville from April 1st 2015. During these two years I will be working on the evolution of hercogamy in flowering plants at Juan Arroyo's lab.
LINK TO RESOLUTION.

* OCTOBER- 3-2014.

50 YEARS DOÑANA BIOLOGICAL STATION.

This year Doñana Biological Station is 50 years old. You can enjoy this wonderful movie about the history of EBD: MOVIE LINK.


* JULY- 3-2014

NEW ACCEPTED PUBLICATION ABOUT PATTERNS OF CHROMOSOME EVOLUTION IN ANGIOSPERMS.

ABSTRACT:
Determining phylogenetic relationships among very closely related species has remained a challenge for evolutionary biologists due to interlocus phylogenetic discordance and the difficulty of obtaining variable markers. Here, we used a Genotyping-by-Sequencing (GBS) approach to sample a reduced representation genomic data set and infer the phylogeny of seven closely related species in the genus
Carex (Cyperaceae). Past attempts to reconstruct phylogenetic relationships among these species produced conflicting and poorly-supported results. We inferred a robust phylogeny based on >3,000 GBS loci and >1,300 SNPs (with a minimum sequence depth within individuals of 10) using maximum likelihood and Bayesian inference. We also tested for historical introgression using the D-statistic test. We compared these analyses with partitioned RAD analysis, which is designed to identify suboptimal trees reflecting secondary phylogenetic signal that may be obscured by the dominant signal in the data. Phylogenetic analyses yielded fully resolved trees with high support. We found two main clades, one grouping Carex scoparia populations and C. waponahkikensis, and a second clade grouping C. longii, C. vexans, C. suberecta and C. albolutescens. We detected marginal significant signals of introgression between C. scoparia and C. suberecta or C. albolutescens, and we rejected a hybrid origin hypothesis for C. waponahkikensis. Our results demonstrate the power of NGS data sets for resolving some of the most difficult phylogenetic challenges where traditional phylogenetic markers have failed.

MARCIAL ESCUDERO, DEREN A.R. EATON, MARLENE HAHN & ANDREW HIPP. 2014. GENOTYPING-BY-SEQUENCING AS A TOOL TO INFER PHYLOGENY AND ANCESTRAL HYBRIDIZATION: A CASE STUDY IN CAREX (CYPERACEAE). MOLECULAR PHYLOGENETICS AND EVOLUTION, 79, 359-367. LINK. PDF.





SELECTED PUBLICATIONS:


1. MARCIAL ESCUDERO, ENRIQUE MAGUILLA & MODESTO LUCEÑO. 2013. SELECTION BY CLIMATIC REGIME AND NEUTRAL EVOLUTIONARY PROCESSES IN HOLOCENTRIC CHROMOSOMES (CAREX GR. LAEVIGATA: CYPERACEAE): A MICROEVOLUTIONARY APPROACH. PERSPECTIVES IN PLANT ECOLOGY, EVOLUTION AND SYSTEMATICS, 15, 118-129. LINKPDF.



2. MARCIAL ESCUDERO, ANDREW HIPP, THOMAS HANSEN, KJETIL VOJE & MODESTO LUCEÑO. 2012. SELECTION AND INERTIA IN THE EVOLUTION OF HOLOCENTRIC CHROMOSOMES IN SEDGES (CAREX, CYPERACEAE). NEW PHYTOLOGIST, 195, 237-247. LINKPDF.

     



3. MARCIAL ESCUDERO, ANDREW HIPP, MARCIA WATERWAY & LUIS VALENTE. 2012. DIVERSIFICATION RATES AND CHROMOSOME EVOLUTION IN THE MOST DIVERSE ANGIOSPERM GENUS OF THE TEMPERATE ZONE (CAREX, CYPERACEAE). MOLECULAR PHYLOGENETICS AND EVOLUTION, 63, 650-655. LINK. PDF.




4. MARCIAL ESCUDERO, PABLO VARGAS, PAUL ARENS, JOOP OUBORG & MODESTO LUCEÑO. 2010. THE EAST-WEST-NORTH COLONIZATION HISTORY OF THE MEDITERRANEAN AND EUROPE BY THE COASTAL PLANT CAREX EXTENSA (CYPERACEAE). MOLECULAR ECOLOGY, 19, 352-370. LINKPDF.



5. MARCIAL ESCUDERO, PABLO VARGAS, VIRGINIA VALCÁRCEL & MODESTO LUCEÑO. 2008. STRAIT OF GIBRALTAR: AN EFFECTIVE GENE-FLOW BARRIER FOR WIND-POLLINATED CAREX HELODES (CYPERACEAE) AS REVEALED BY DNA SEQUENCES, AFLP, AND CYTOGENETIC VARIATION. AMERICAN JOURNAL OF BOTANY, 95, 745-755. LINKPDF.




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