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Fernandez-Mazuecos M.,Real Jardin Botanico RJB CSIC | Blanco-Pastor J.L.,Real Jardin Botanico RJB CSIC | Gomez J.M.,Estacion Experimental de ZonasAridas EEZA CSIC | Gomez J.M.,University of Granada | Vargas P.,Real Jardin Botanico RJB CSIC
Annals of Botany | Year: 2013

Background and Aims The role of flower specialization in plant speciation and evolution remains controversial. In this study the evolution of flower traits restricting access to pollinators was analysed in the bifid toadflaxes (Linaria sect. Versicolores), a monophyletic group of 30 species and subspecies with highly specialized corollas. Methods A time-calibrated phylogeny based on both nuclear and plastid DNA sequences was obtained using a coalescent- based method, and flower morphology was characterized by means of morphometric analyses. Directional trends in flower shape evolution and trait-dependent diversification rates were jointly analysed using recently developed methods, and morphological shiftswere reconstructed along the phylogeny. Pollinator surveyswere conducted for a representative sample of species. KeyResultsArestrictive character state (narrowcorolla tube)was reconstructed in themost recentcommonancestor of Linaria sect. Versicolores. After its early loss in the most species-rich clade, this character state has been convergently reacquired in multiple lineages of this clade in recent times, yet it seems to have exerted a negative influence on diversification rates. Comparative analyses and pollinator surveys suggest that the narrow- and broad-tubed flowers are evolutionary optima representing divergent strategies of pollen placement on nectar-feeding insects. Conclusions The results confirm that different forms of floral specialization can lead to dissimilar evolutionary success in terms of diversification. It is additionally suggested that opposing individual-level and species-level selection pressures may have driven the evolution of pollinator-restrictive traits in bifid toadflaxes. © The Author 2013.


Inda L.A.,University of Zaragoza | Sanmartin I.,Real Jardin Botanico RJB CSIC | Buerki S.,Jodrell Laboratory | Catalan P.,University of Zaragoza
Journal of Biogeography | Year: 2014

Aim: The biogeography of the grass genera Festuca (subgenus Schedonorus) and Lolium, which form one of the world main forage groups, is here reconstructed for the first time using nuclear and plastid DNA data. We aimed to test previous hypotheses on the origin of the group ancestor and on the Holocene versus pre-Holocene dispersals of the most recent fodder grasses. Location: The Mediterranean Basin and neighbouring regions: North Africa, Southwest Asia, East and West Africa, and Eurasia. Methods: Sampling included nearly all representatives from the native Old World distribution of this group. We used maximum parsimony, maximum likelihood and Bayesian inference methods to reconstruct phylogenetic relationships. Divergence times were estimated with a Bayesian relaxed clock and secondary calibrations derived from a fossil-dated phylogeny of grasses. Biogeographical scenarios were reconstructed with Bayesian-averaged dispersal-vicariance analysis (Bayes-DIVA) and dispersal-extinction-cladogenesis (DEC), using a stratified palaeogeographical model spanning the last 12 million years. Results: Meadow fescue (Festuca pratensis) originated in Eurosiberia, Southwest Asia, 2 million years ago (Ma), whereas ryegrasses (Lolium) first diversified in the eastern Mediterranean region around 4.1 Ma, splitting into two autogamous versus allogamous lineages, with Macaronesian Lolium embedded within the latter. An alternative scenario suggests, however, an early split of the Macaronesian ryegrasses. Our results support the hybrid origin of the tall fescue (Festuca arundinacea). Main conclusions: The ancestor of the fescues and ryegrasses originated in the western Mediterranean in the mid-Miocene. The sister relationship of the tropical African Festuca simensis to Lolium is a novel finding, suggesting a dispersal of the ancestor of the ryegrasses from Asia to East Africa in the early Pliocene. Our reconstruction rejects the hypothesis of a single Neolithic human-mediated dispersal of Lolium species from eastern to western Mediterranean areas, suggesting instead a pre-agricultural distribution of Lolium ancestors along the Mediterranean Basin since the Pliocene. © 2013 John Wiley & Sons Ltd.


Vitales D.,University of Barcelona | Garnatje T.,Institute Botanic Of Barcelona Ibb Csic Icub | Pellicer J.,Jodrell Laboratory | Valles J.,University of Barcelona | And 2 more authors.
BMC Evolutionary Biology | Year: 2014

Background: Considered a biodiversity hotspot, the Canary Islands have been the key subjects of numerous evolutionary studies concerning a large variety of organisms. The genus Cheirolophus (Asteraceae) represents one of the largest plant radiations in the Canarian archipelago. In contrast, only a few species occur in the Mediterranean region, the putative ancestral area of the genus. Here, our main aim was to reconstruct the phylogenetic and biogeographic history of Cheirolophus with special focus on explaining the origin of the large Canarian radiation. Results: We found significant incongruence in phylogenetic relationships between nuclear and plastid markers. Each dataset provided resolution at different levels in Cheirolophus: the nuclear markers resolved the backbone of the phylogeny while the plastid data provided better resolution within the Canarian clade. The origin of Cheirolophus was dated in the Mid-Late Miocene, followed by rapid diversification into the three main Mediterranean lineages and the Macaronesian clade. A decrease in diversification rates was inferred at the end of the Miocene, with a new increase in the Late Pliocene concurrent with the onset of the Mediterranean climate. Diversification within the Macaronesian clade started in the Early-Mid Pleistocene, with unusually high speciation rates giving rise to the extant insular diversity. Conclusions: Climate-driven diversification likely explains the early evolutionary history of Cheirolophus in the Mediterranean region. It appears that the exceptionally high diversification rate in the Canarian clade was mainly driven by allopatric speciation (including intra- and interisland diversification). Several intrinsic (e.g. breeding system, polyploid origin, seed dispersal syndrome) and extrinsic (e.g. fragmented landscape, isolated habitats, climatic and geological changes) factors probably contributed to the progressive differentiation of populations resulting in numerous microendemisms. Finally, hybridization events and emerging ecological adaptation may have also reinforced the diversification process. © 2014 Vitales et al.; licensee BioMed Central Ltd.


Mateo R.G.,Real Jardin Botanico RJB CSIC | de la Estrella M.,University of Cordoba, Spain | Felicisimo A.M.,University of Extremadura | Munoz J.,Real Jardin Botanico RJB CSIC | And 2 more authors.
Biological Conservation | Year: 2013

Knowledge about spatial biodiversity patterns is a basic criterion for reserve network design. Although herbarium collections hold large quantities of information, the data are often scattered and cannot supply complete spatial coverage. Alternatively, herbarium data can be used to fit species distribution models and their predictions can be used to provide complete spatial coverage and derive species richness maps. Here, we build on previous effort to propose an improved compositionalist framework for using species distribution models to better inform conservation management. We illustrate the approach with models fitted with six different methods and combined using an ensemble approach for 408 plant species in a tropical and megadiverse country (Ecuador). As a complementary view to the traditional richness hotspots methodology, consisting of a simple stacking of species distribution maps, the compositionalist modelling approach used here combines separate predictions for different pools of species to identify areas of alternative suitability for conservation. Our results show that the compositionalist approach better captures the established protected areas than the traditional richness hotspots strategies and allows the identification of areas in Ecuador that would optimally complement the current protection network. Further studies should aim at refining the approach with more groups and additional species information. © 2013 Elsevier Ltd.


Fernandez-Mazuecos M.,Real Jardin Botanico RJB CSIC | Jimenez-Mejias P.,Real Jardin Botanico RJB CSIC | Jimenez-Mejias P.,Washington State University | Rotllan-Puig X.,CSIC - Mediterranean Institute for Advanced Studies | Vargas P.,Real Jardin Botanico RJB CSIC
Perspectives in Plant Ecology, Evolution and Systematics | Year: 2014

Narrow endemics constitute the cornerstone of Mediterranean plant diversity. Naufraga balearica (Apiaceae) is a critically endangered, extremely narrow endemic plant from the western Mediterranean island of Majorca. Because the species belongs to a monotypic genus, N. balearica was hypothesized to be a palaeoendemism. Here we conducted phylogenetic dating, population genetic and climatic niche analyses in order to understand the evolutionary history and conservation perspectives of this flagship species. Phylogenetic dating analysis of nuclear and plastid DNA sequences revealed a late Miocene to early Pliocene divergence between Naufraga and its sister genus Apium, supporting the palaeoendemic status of the former. Amplified fragment length polymorphism (AFLP) markers and plastid DNA sequences of the five Naufraga populations revealed moderate genetic diversity. This diversity is in line with that of other palaeoendemisms from western Mediterranean islands, as revealed by a comparison with 22 other narrow endemic species from this region. Despite the fact that all Naufraga populations are located at a maximum distance of 10. km in a straight line, a strikingly strong population differentiation was found for AFLP markers, which is explained by long-term isolation likely related to short-range pollination and dispersal strategies of the species. While the species is not genetically impoverished, species distribution modelling and microclimatic monitoring revealed that narrow ecological requirements underlie the current extreme rarity of Naufraga and may jeopardize its long-term survival. Our results indicate that a multidisciplinary approach provides powerful tools to develop conservation strategies for evolutionarily singular lineages. © 2014 Geobotanisches Institut ETH, Stiftung Ruebel.


Blanco-Pastor J.L.,Real Jardin Botanico RJB CSIC | Vargas P.,Real Jardin Botanico RJB CSIC | Pfeil B.E.,Gothenburg University
PLoS ONE | Year: 2012

We examined the phylogenetic history of Linaria with special emphasis on the Mediterranean sect. Supinae (44 species). We revealed extensive highly supported incongruence among two nuclear (ITS, AGT1) and two plastid regions (rpl32-trnLUAG, trnS-trnG). Coalescent simulations, a hybrid detection test and species tree inference in *BEAST revealed that incomplete lineage sorting and hybridization may both be responsible for the incongruent pattern observed. Additionally, we present a multilabelled *BEAST species tree as an alternative approach that allows the possibility of observing multiple placements in the species tree for the same taxa. That permitted the incorporation of processes such as hybridization within the tree while not violating the assumptions of the *BEAST model. This methodology is presented as a functional tool to disclose the evolutionary history of species complexes that have experienced both hybridization and incomplete lineage sorting. The drastic climatic events that have occurred in the Mediterranean since the late Miocene, including the Quaternary-type climatic oscillations, may have made both processes highly recurrent in the Mediterranean flora. © 2012 Blanco-Pastor et al.


The role of Quaternary climatic shifts in shaping the distribution of Linaria elegans, an Iberian annual plant, was investigated using species distribution modelling and molecular phylogeographical analyses. Three hypotheses are proposed to explain the Quaternary history of its mountain ring range. The distribution of L. elegans was modelled using the maximum entropy method and projected to the last interglacial and to the last glacial maximum (LGM) using two different paleoclimatic models: the Community Climate System Model (CCSM) and the Model for Interdisciplinary Research on Climate (MIROC). Two nuclear and three plastid DNA regions were sequenced for 24 populations (119 individuals sampled). Bayesian phylogenetic, phylogeographical, dating and coalescent-based population genetic analyses were conducted. Molecular analyses indicated the existence of northern and southern glacial refugia and supported two routes of post-glacial recolonization. These results were consistent with the LGM distribution as inferred under the CCSM paleoclimatic model (but not under the MIROC model). Isolation between two major refugia was dated back to the Riss or Mindel glaciations, > 100 kyr before present (bp). The Atlantic distribution of inferred refugia suggests that the oceanic (buffered)-continental (harsh) gradient may have played a key and previously unrecognized role in determining Quaternary distribution shifts of Mediterranean plants. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.


Mendoza-Cifuentes H.,National University of Colombia | Fernandez-Alonso J.L.,Real Jardin Botanico RJB CSIC
Anales del Jardin Botanico de Madrid | Year: 2012

A historical review, the circumscription problems and nomenclatural changes based upon a phylogenetic morphological analysis of the genus Centronia are presented. In this framework, four Andean species of Centronia are transfered to thegenus Meriania (M. brachycera, M. haemantha, M. mutabilis and M. mutisii) and five new speciesrelated to this group (M. aguaditensis, M. arizae, M. silverstonei, M. sararensis and M. yalconensis) and three new subspecies of M. haemantha (subsp. chaponensis, subsp. orientalis and subsp. virolinensis) are described. The selection of lectotypes of M. haemantha and M. mutisii is made and four names Centronia eximia, C. pulchra, C. dichromantha and C. insignis, are considered synonyms. We argue that this group of nine species is a natural group witthin the genus Meriania, and present taxonomic revision.


Mairal M.,Real Jardin Botanico RJB CSIC | Pokorny L.,Real Jardin Botanico RJB CSIC | Aldasoro J.J.,Institute Botanic Of Barcelona Ibb Csic | Alarcon M.,Institute Botanic Of Barcelona Ibb Csic | Sanmartin I.,Real Jardin Botanico RJB CSIC
Molecular Ecology | Year: 2015

Transoceanic distributions have attracted the interest of scientists for centuries. Less attention has been paid to the evolutionary origins of 'continent-wide' disjunctions, in which related taxa are distributed across isolated regions within the same continent. A prime example is the 'Rand Flora' pattern, which shows sister taxa disjunctly distributed in the continental margins of Africa. Here, we explore the evolutionary origins of this pattern using the genus Canarina, with three species: C. canariensis, associated with the Canarian laurisilva, and C. eminii and C. abyssinica, endemic to the Afromontane region in East Africa, as case study. We infer phylogenetic relationships, divergence times and the history of migration events within Canarina using Bayesian inference on a large sample of chloroplast and nuclear sequences. Ecological niche modelling was employed to infer the climatic niche of Canarina through time. Dating was performed with a novel nested approach to solve the problem of using deep time calibration points within a molecular dataset comprising both above-species and population-level sampling. Results show C. abyssinica as sister to a clade formed by disjunct C. eminii and C. canariensis. Miocene divergences were inferred among species, whereas infraspecific divergences fell within the Pleistocene-Holocene periods. Although C. eminii and C. canariensis showed a strong genetic geographic structure, among-population divergences were older in the former than in the latter. Our results suggest that Canarina originated in East Africa and later migrated across North Africa, with vicariance and aridification-driven extinction explaining the 7000 km/7 million year divergence between the Canarian and East African endemics. © 2015 John Wiley & Sons Ltd.


Blanco-Pastor J.L.,Real Jardin Botanico RJB CSIC | Fernandez-Mazuecos M.,Real Jardin Botanico RJB CSIC | Vargas P.,Real Jardin Botanico RJB CSIC
Molecular Ecology | Year: 2013

Anthropogenic global climate change is expected to cause severe range contractions among alpine plants. Alpine areas in the Mediterranean region are of special concern because of the high abundance of endemic species with narrow ranges. This study combined species distribution models, population structure analyses and Bayesian skyline plots to trace the past and future distribution and diversity of Linaria glacialis, an endangered narrow endemic species that inhabits summits of Sierra Nevada (Spain). The results showed that: (i) the habitat of this alpine-Mediterranean species in Sierra Nevada suffered little changes during glacial and interglacial stages of late Quaternary; (ii) climatic oscillations in the last millennium (Medieval Warm Period and Little Ice Age) moderately affected the demographic trends of L. glacialis; (iii) future warming conditions will cause severe range contractions; and (iv) genetic diversity will not diminish at the same pace as the distribution range. As a consequence of the low population structure of this species, genetic impoverishment in the alpine zones of Sierra Nevada should be limited during range contraction. We conclude that maintenance of large effective population sizes via high mutation rates and high levels of gene flow may promote the resilience of alpine plant species when confronted with global warming. © 2013 John Wiley & Sons Ltd.

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