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1.
Hist Philos Life Sci ; 42(4): 43, 2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-32996022

RESUMEN

What is it to make an error in the identification of a named taxonomic group? In this article we argue that the conditions for being in error about the identity of taxonomic groups through their names have a history, and that the possibility of committing such errors is contingent on the regime of institutions and conventions governing taxonomy and nomenclature at any given point in time. More specifically, we claim that taxonomists today can be in error about the identity of taxonomic groups in a way that Carl Linnaeus (1707-1778), who is routinely cited as the "founder" of modern taxonomy and nomenclature, simply could not be. Starting from a remarkable recent study into Linnaeus's naming of Elephas maximus that led to the (putative) discovery of a (putative) nomenclatural error by him, we reconsider what it could mean to discover that Linnaeus misidentified a biological taxon in applying his taxon names. Through a further case study in Linnaean botany, we show that his practices of (re)applying names in taxonomic revisions reveal a take on determining "which taxon is which" that is strikingly different from that of contemporary taxonomists. Linnaeus, we argue, adopted a practice-based, hands-on concept of taxa as "nominal spaces" that could continue to represent the same taxon even if all its former members had been reallocated to other taxa.


Asunto(s)
Botánica/historia , Campanulaceae/clasificación , Clasificación/métodos , Elefantes/clasificación , Orobanchaceae/clasificación , Terminología como Asunto , Zoología/historia , Animales , Historia del Siglo XVIII
2.
PLoS One ; 15(5): e0233167, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32407424

RESUMEN

The conflicts exist between the phylogeny of Campanulaceae based on nuclear ITS sequence and plastid markers, particularly in the subdivision of Cyanantheae (Campanulaceae). Besides, various and complicated plastid genome structures can be found in species of the Campanulaceae. However, limited availability of genomic information largely hinders the studies of molecular evolution and phylogeny of Campanulaceae. We reported the complete plastid genomes of three Cyanantheae species, compared them to eight published Campanulaceae plastomes, and shed light on a deeper understanding of the applicability of plastomes. We found that there were obvious differences among gene order, GC content, gene compositions and IR junctions of LSC/IRa. Almost all protein-coding genes and amino acid sequences showed obvious codon preferences. We identified 14 genes with highly positively selected sites and branch-site model displayed 96 sites under potentially positive selection on the three lineages of phylogenetic tree. Phylogenetic analyses showed that Cyananthus was more closely related to Codonopsis compared with Cyclocodon and also clearly illustrated the relationship among the Cyanantheae species. We also found six coding regions having high nucleotide divergence value. Hotpot regions were considered to be useful molecular markers for resolving phylogenetic relationships and species authentication of Campanulaceae.


Asunto(s)
Campanulaceae/clasificación , Campanulaceae/genética , Genoma de Plastidios/genética , Filogenia , Codón de Terminación/genética , Secuencias Invertidas Repetidas/genética , Repeticiones de Microsatélite/genética , Sistemas de Lectura Abierta/genética , Selección Genética
3.
Mol Phylogenet Evol ; 152: 106769, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32081762

RESUMEN

Targeted sequence capture is a promising approach for large-scale phylogenomics. However, rapid evolutionary radiations pose significant challenges for phylogenetic inference (e.g. incomplete lineages sorting (ILS), phylogenetic noise), and the ability of targeted nuclear loci to resolve species trees despite such issues remains poorly studied. We test the utility of targeted sequence capture for inferring phylogenetic relationships in rapid, recent angiosperm radiations, focusing on Burmeistera bellflowers (Campanulaceae), which diversified into ~130 species over less than 3 million years. We compared phylogenies estimated from supercontig (exons plus flanking sequences), exon-only, and flanking-only datasets with 506-546 loci (~4.7 million bases) for 46 Burmeistera species/lineages and 10 outgroup taxa. Nuclear loci resolved backbone nodes and many congruent internal relationships with high support in concatenation and coalescent-based species tree analyses, and inferences were largely robust to effects of missing taxa and base composition biases. Nevertheless, species trees were incongruent between datasets, and gene trees exhibited remarkably high levels of conflict (~4-60% congruence, ~40-99% conflict) not simply driven by poor gene tree resolution. Higher gene tree heterogeneity at shorter branches suggests an important role of ILS, as expected for rapid radiations. Phylogenetic informativeness analyses also suggest this incongruence has resulted from low resolving power at short internal branches, consistent with ILS, and homoplasy at deeper nodes, with exons exhibiting much greater risk of incorrect topologies due to homoplasy than other datasets. Our findings suggest that targeted sequence capture is feasible for resolving rapid, recent angiosperm radiations, and that results based on supercontig alignments containing nuclear exons and flanking sequences have higher phylogenetic utility and accuracy than either alone. We use our results to make practical recommendations for future target capture-based studies of Burmeistera and other rapid angiosperm radiations, including that such studies should analyze supercontigs to maximize the phylogenetic information content of loci.


Asunto(s)
Campanulaceae/clasificación , Clasificación/métodos , Filogenia , Evolución Biológica
4.
Mol Phylogenet Evol ; 127: 468-474, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29723647

RESUMEN

The Campanulaceae comprises approximately 2300 species that are distributed among five major lineages: Campanuloideae, Cyphioideae, Cyphocarpoideae, Lobelioideae, and Nemacladoideae. Of these, the Campanuloideae, a primarily Old World clade, has the largest diversity in East Asia. In this study, we reconstruct the phylogeny of East Asian Campanuloideae based on one nuclear gene (i.e., PPR70) and five plastid markers (i.e., atpB, matK, petD, rbcL, and trnL-trnF). We then use this phylogenetic framework to reconstruct the biogeographical history of the genus. Our molecular dataset includes 376 of the 1045 currently recognized species in the Campanuloideae. Of the 376 sampled species, 116 are from East Asia, representing ca. 60% of the East Asian Campanuloideae. Our PPR dataset included sequences for 156 accessions, representing 54 species, while our plastid dataset included sequences for 305 accessions, representing 354 species. Phylogenetic analyses recovered three large clades containing East Asian taxa: Campanulinae, Platycodinae, and Wahlenberginae. The historical assembly of Campanuloideae diversity in East Asia appears to have resulted from numerous, independent movements from Africa, Europe/W. Asia, and North America. Africa was inferred as the ancestral range for the Campanuloideae. Movement of the largest East Asian clade (Platycodinae) occurred at approximately 53.1 Ma (46.6-58.73 95% HPD) from Africa, with much of the current diversity found in East Asia having resulted from in situ diversification. Thirteen additional movements into East Asia, primarily from Europe/Western Asia, occurred subsequently. One dispersal event from western North America was also inferred. In contrast, only six movements out of East Asia were found. Our results suggest that East Asia has acted primarily as a sink for Campanuloideae diversity, with Europe, Western Asia, and Africa representing major source areas.


Asunto(s)
Evolución Biológica , Campanulaceae/clasificación , Campanulaceae/genética , Variación Genética , Núcleo Celular/genética , Asia Oriental , Funciones de Verosimilitud , Filogenia , Filogeografía , Plastidios/genética , Factores de Tiempo
5.
PLoS One ; 12(8): e0183652, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28829825

RESUMEN

We report the complete chloroplast genomes of three Adenophora species, and analyzed these compared them to five published Campanuloid plastomes. The total genome length of Adenophora divaricata, Adenophora erecta, and Adenophora stricta ranged from 159,759 to 176,331 bp. Among the eight Campanuloid species, many inversions were found to be only in the LSC region. IR contraction was also identified in the plastid genome of Adenophora stricta. Phylogenetic analyses based on 76 protein coding genes showed that Campanuloids are monophyletic, and are composed of two major groups: Campanula s. str. and Rapunculus. When we compared each homologous locus among the four Adenophora species, ten regions showed high nucleotide divergence value (>0.03). Among these, nine loci, excepting ycf3-rpoB, are considered to be useful molecular markers for phylogenetic studies and will be helpful to resolve phylogenetic relationships of Adenophora.


Asunto(s)
Campanulaceae/genética , Cloroplastos/genética , Genoma de Planta , Campanulaceae/clasificación , Marcadores Genéticos , Filogenia , Especificidad de la Especie
6.
Evolution ; 71(4): 913-922, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28186341

RESUMEN

The Mediterranean Basin harbors a remarkable amount of biodiversity, a high proportion of which is endemic to this region. Here, we present an in-depth study of an angiosperm species complex, in which cryptic taxonomic diversity has been hypothesized. Specifically, we focus on four currently recognized species in the Roucela complex, a well-supported clade in the Campanulaceae/Campanuloideae: Campanula creutzburgii, C. drabifolia, C. erinus, and C. simulans. This study takes a phylogenomic approach, utilizing near-complete plastomes and 130 nuclear loci, to uncover cryptic diversity and test hypotheses regarding hybridization and polyploidy within this clade. Genome size estimates recovered tetraploid and octoploid lineages within the currently recognized, widespread species C. erinus, showing an east-west geographic pattern. Though genomic data clearly differentiate these two cytotypes, we failed to discern morphological differences. The formation of a cryptic octoploid lineage, distributed across the eastern Mediterranean, is hypothesized to be the result of an allopolyploid event in which one parental morphology is retained. The tetraploid C. erinus and C. creutzburgii (also a tetraploid) are implicated as parental lineages. Our results highlight the utility of target-enrichment approaches for obtaining genomic datasets for thorough assessments of species diversity and the importance of carefully considering gene-tree discordance within such datasets.


Asunto(s)
Biodiversidad , Campanulaceae/clasificación , Campanulaceae/genética , Filogenia , Poliploidía , Genoma de Planta , Hibridación Genética , Región Mediterránea , Filogeografía , Análisis de Secuencia de ADN
7.
Mol Phylogenet Evol ; 107: 551-563, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28011338

RESUMEN

The field of molecular systematics has benefited greatly with the advent of high-throughput sequencing (HTS), making large genomic datasets commonplace. However, a large number of targeted Sanger sequences produced by many studies over the last two decades are publicly available and should not be overlooked. In this study, we elucidate the phylogenetic relationships of the plant genus Burmeistera (Campanulaceae: Lobelioideae), while investigating how to best combine targeted Sanger loci with HTS data. We sequence, annotate, and analyze complete to nearly complete plastomes for a subset of the genus. We then combine these data with a much larger taxonomic dataset for which only Sanger sequences are available, making this the most comprehensively sampled study in the genus to date. We show that using a phylogeny inferred from the species with plastome data as a topological constraint for the larger dataset increases the resolution of our data and produces a more robust evolutionary hypothesis for the group. We then use the resulting phylogeny to study the evolution of morphological traits thought to be important in Burmeistera, and assess their usefulness in the current taxonomic classification of the genus. The main morphological character used to delimit subgeneric sections, the presence or absence of hairs on the apex of the two ventral anthers, shows a complex evolutionary history with many changes in the tree, suggesting that this character should not be used for taxonomic classification. Although it is too soon to propose a new subgeneric classification for Burmeistera, our results highlight some morphological traits shared by whole clades that could potentially be used in future taxonomic work.


Asunto(s)
Campanulaceae/clasificación , Campanulaceae/genética , Sitios Genéticos , Genoma de Plastidios , Filogenia , Secuencia de Bases , Secuenciación de Nucleótidos de Alto Rendimiento , Fenotipo
8.
Am J Bot ; 103(2): 233-45, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26865121

RESUMEN

PREMISE OF THE STUDY: The Campanulaceae are a diverse clade of flowering plants encompassing more than 2300 species in myriad habitats from tropical rainforests to arctic tundra. A robust, multigene phylogeny, including all major lineages, is presented to provide a broad, evolutionary perspective of this cosmopolitan clade. METHODS: We used a phylogenetic framework, in combination with divergence dating, ancestral range estimation, chromosome modeling, and morphological character reconstruction analyses to infer phylogenetic placement and timing of major biogeographic, genomic, and morphological changes in the history of the group and provide insights into the diversification of this clade across six continents. KEY RESULTS: Ancestral range estimation supports an out-of-Africa diversification following the Cretaceous-Tertiary extinction event. Chromosomal modeling, with corroboration from the distribution of synonymous substitutions among gene duplicates, provides evidence for as many as 20 genome-wide duplication events before large radiations. Morphological reconstructions support the hypothesis that switches in floral symmetry and anther dehiscence were important in the evolution of secondary pollen presentation mechanisms. CONCLUSIONS: This study provides a broad, phylogenetic perspective on the evolution of the Campanulaceae clade. The remarkable habitat diversity and cosmopolitan distribution of this lineage appears to be the result of a complex history of genome duplications and numerous long-distance dispersal events. We failed to find evidence for an ancestral polyploidy event for this clade, and our analyses indicate an ancestral base number of nine for the group. This study will serve as a framework for future studies in diverse areas of research in Campanulaceae.


Asunto(s)
Evolución Biológica , Campanulaceae/clasificación , Campanulaceae/genética , Filogenia , Evolución Molecular , Genes de Plantas , Análisis de Secuencia de ADN
9.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(4): 2963-4, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26119125

RESUMEN

The complete chloroplast genome of Adenophora remotiflora was determined in this study. The total genome size was 171 724 bp in length, containing a pair of inverted repeats of 27 437 bp, which were separated by large single copy and small single copy of 105 555 bp and 11 295 bp, respectively. The overall GC contents of the plastid genome were 38.8%. One hundred and twelve unique genes were annotated, including 78 protein coding genes, 30 tRNA genes and 4 rRNA genes. In these genes, 15 genes contained one intron and 2 genes had two introns. A phylogenetic tree showed that Adenophora remotiflora was closely related to Hanabusaya asiatica.


Asunto(s)
Campanulaceae/clasificación , Campanulaceae/genética , Genoma del Cloroplasto , Composición de Base , Genes del Cloroplasto , Tamaño del Genoma , Sistemas de Lectura Abierta , Filogenia , Análisis de Secuencia de ADN , Secuenciación Completa del Genoma
10.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 1629-31, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-25208164

RESUMEN

The complete chloroplast genome of Hanabusaya asiatica, an endemic genus to Korea, was determined in this study. The total genome size was 167,287 bp in length, containing a pair of inverted repeats (IRs) of 26,877 bp, which were separated by large single copy (LSC) and small single copy (SSC) of 104,955 and 8578, respectively. The overall GC contents of the plastid genome were 38.8%. One hundred and twelve unique genes were annotated, including 78 protein coding genes, 30 tRNA genes and 4 rRNA genes. In these genes, 17 genes contained 1 intron, and 2 genes comprised of 2 introns.


Asunto(s)
Campanulaceae/genética , Genoma del Cloroplasto/genética , Composición de Base/genética , Campanulaceae/clasificación , ADN de Cloroplastos/genética , Genoma Mitocondrial/genética , Genoma de Planta/genética , Corea (Geográfico) , Análisis de Secuencia de ADN
11.
Mol Ecol ; 24(6): 1335-54, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25688489

RESUMEN

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.


Asunto(s)
Evolución Biológica , Campanulaceae/clasificación , Clima , Extinción Biológica , Filogenia , África , Teorema de Bayes , ADN de Cloroplastos/genética , ADN de Plantas/genética , Modelos Genéticos , Análisis de Secuencia de ADN
12.
Am J Bot ; 101(12): 2097-112, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25480707

RESUMEN

UNLABELLED: • PREMISE OF THE STUDY: The species-rich Neotropical genera Centropogon, Burmeistera, and Siphocampylus represent more than half of the ∼1200 species in the subfamily Lobelioideae (Campanulaceae). They exhibit remarkable morphological variation in floral morphology and habit. Limited taxon sampling and phylogenetic resolution, however, obscures our understanding of relationships between and within these genera and underscores our uncertainty of the systematic value of fruit type as a major diagnostic character.• METHODS: We inferred a phylogeny from five plastid DNA regions (rpl32-trnL, ndhF-rpl32, rps16-trnK, trnG-trnG-trns, rbcL) using maximum-likelihood and Bayesian inference. Ancestral character reconstructions were applied to infer patterns of fruit evolution.• KEY RESULTS: Our results demonstrate that the majority of species in the genera Centropogon, Burmeistera, and Siphocampylus together form a primarily mainland Neotropical clade, collectively termed the "centropogonids." Caribbean Siphocampylus, however, group with other Caribbean lobelioid species. We find high support for the monophyly of Burmeistera and the polyphyly of Centropogon and mainland Siphocampylus. The ancestral fruit type of the centropogonids is a capsule; berries have evolved independently multiple times.• CONCLUSIONS: Our plastid phylogeny greatly improves the phylogenetic resolution within Neotropical Lobelioideae and highlights the need for taxonomic revisions in the subfamily. Inference of ancestral character states identifies a dynamic pattern of fruit evolution within the centropogonids, emphasizing the difficulty of diagnosing broad taxonomic groups on the basis of fruit type. Finally, we identify that the centropogonids, Lysipomia, and Lobelia section Tupa form a Pan-Andean radiation with broad habitat diversity. This clade is a prime candidate for investigations of Neotropical biogeography and morphological evolution.


Asunto(s)
Evolución Biológica , Campanulaceae/genética , ADN de Plantas/análisis , Frutas/anatomía & histología , Filogenia , Teorema de Bayes , Campanulaceae/anatomía & histología , Campanulaceae/clasificación , Región del Caribe , Clasificación , Ecosistema , Evolución Molecular , Plastidios , Análisis de Secuencia de ADN , Especificidad de la Especie
13.
PLoS One ; 9(11): e113336, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25409036

RESUMEN

Among latex-producing plants, mainly the latex of Hevea brasiliensis has been studied in detail so far, while comprehensive comparative studies of latex coagulation mechanisms among the more than 20,000 latex-bearing plant species are lacking. In order to give new insights into the potential variety of coagulation mechanisms, the untreated natural latices of five latex-bearing plants from the families Euphorbiaceae, Moraceae and Campanulaceae were visualised using Cryo-SEM and their particle size compared using the laser diffraction method. Additionally, the laticifers of these plants species were examined in planta via Cryo-SEM. Similar latex particle sizes and shape were found in Ficus benjamina and Hevea brasiliensis. Hence, and due to other similarities, we hypothesize comparable, mainly chemical, coagulation mechanisms in these two species, whereas a physical coagulation mechanism is proposed for the latex of Euphorbia spp. The latter mechanism is based on the huge amount of densely packed particles that after evaporation of water build a large surface area, which accelerates the coagulation procedure.


Asunto(s)
Campanulaceae/química , Euphorbia/química , Ficus/química , Látex/química , Campanulaceae/clasificación , Campanulaceae/metabolismo , Microscopía por Crioelectrón/métodos , Euphorbia/clasificación , Euphorbia/metabolismo , Ficus/clasificación , Ficus/metabolismo , Rayos Láser , Tamaño de la Partícula , Filogenia
14.
PLoS One ; 9(4): e94199, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24718519

RESUMEN

BACKGROUND: The Campanuloideae (Campanulaceae) are a highly diverse clade of angiosperms found mostly in the Northern Hemisphere, with the highest diversity in temperate areas of the Old World. Chloroplast markers have greatly improved our understanding of this clade but many relationships remain unclear primarily due to low levels of molecular evolution and recent and rapid divergence. Furthermore, focusing solely on maternally inherited markers such as those from the chloroplast genome may obscure processes such as hybridization. In this study we explore the phylogenetic utility of two low-copy nuclear loci from the pentatricopeptide repeat gene family (PPR). Rapidly evolving nuclear loci may provide increased phylogenetic resolution in clades containing recently diverged or closely related taxa. We present results based on both chloroplast and low-copy nuclear loci and discuss the utility of such markers to resolve evolutionary relationships and infer hybridization events within the Campanuloideae clade. RESULTS: The inclusion of low-copy nuclear genes into the analyses provides increased phylogenetic resolution in two species-rich clades containing recently diverged taxa. We also obtain support for the placement of two early diverging lineages (Jasione and Musschia-Gadellia clades) that have previously been unresolved. Furthermore, phylogenetic analyses of PPR loci revealed potential hybridization events for a number of taxa (e.g., Campanula pelviformis and Legousia species). These loci offer greater overall topological support than obtained with plastid DNA alone. CONCLUSION: This study represents the first inclusion of low-copy nuclear genes for phylogenetic reconstruction in Campanuloideae. The two PPR loci were easy to sequence, required no cloning, and the sequence alignments were straightforward across the entire Campanuloideae clade. Although potentially complicated by incomplete lineage sorting, these markers proved useful for understanding the processes of reticulate evolution and resolving relationships at a wide range of phylogenetic levels. Our results stress the importance of including multiple, independent loci in phylogenetic analyses.


Asunto(s)
Campanulaceae/clasificación , Genes de Plantas , Campanulaceae/genética , ADN de Cloroplastos/genética , ADN de Plantas/genética , Evolución Molecular , Dosificación de Gen , Marcadores Genéticos , Variación Genética , Familia de Multigenes , Filogenia , Proteínas de Plantas/genética , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
15.
PLoS One ; 8(10): e73854, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24146742

RESUMEN

Numerous widespread Alpine plant species show molecular differentiation among populations from distinct regions. This has been explained as the result of genetic drift during glacial survival in isolated refugia along the border of the European Alps. Since genetic drift may affect molecular markers and phenotypic traits alike, we asked whether phenotypic differentiation mirrors molecular patterns among Alpine plant populations from different regions. Phenotypic traits can be under selection, so we additionally investigated whether part of the phenotypic differentiation can be explained by past selection and/or current adaptation. Using the monocarpic Campanula thyrsoides as our study species, a common garden experiment with plants from 21 populations from four phylogeographic groups located in regions across the Alps and the Jura Mountains was performed to test for differentiation in morphological and phenological traits. Past selection was investigated by comparing phenotypic differentiation among and within regions with molecular differentiation among and within regions. The common garden results indicated regional differentiation among populations for all investigated phenotypic traits, particularly in phenology. Delayed flowering in plants from the South-eastern Alps suggested adaptation to long sub-mediterranean summers and contrasted with earlier flowering of plants experiencing shorter growing seasons in regions with higher elevation to the West. Comparisons between molecular and phenotypic differentiation revealed diversifying selection among regions in height and biomass, which is consistent with adaptation to environmental conditions in glacial refugia. Within regions, past selection acted against strong diversification for most phenotypic traits, causing restricted postglacial adaptation. Evidence consistent with post-glacial adaptation was also given by negative correlation coefficients between several phenotypic traits and elevation of the population's origin. In conclusion, our study suggests that, irrespective of adaptation of plants to their current environment, glacial history can have a strong and long-lasting influence on the phenotypic evolution of Alpine plants.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Campanulaceae/genética , Variación Genética , Fenotipo , Altitud , Campanulaceae/anatomía & histología , Campanulaceae/clasificación , Ecosistema , Flujo Genético , Cubierta de Hielo , Filogeografía , Dispersión de las Plantas/fisiología , Selección Genética , Suiza , Factores de Tiempo
16.
Biomed Res Int ; 2013: 503193, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24069602

RESUMEN

Existing algorithms allow us to infer phylogenetic networks from sequences (DNA, protein or binary), sets of trees, and distance matrices, but there are no methods to build them using the gene order data as an input. Here we describe several methods to build split networks from the gene order data, perform simulation studies, and use our methods for analyzing and interpreting different real gene order datasets. All proposed methods are based on intermediate data, which can be generated from genome structures under study and used as an input for network construction algorithms. Three intermediates are used: set of jackknife trees, distance matrix, and binary encoding. According to simulations and case studies, the best intermediates are jackknife trees and distance matrix (when used with Neighbor-Net algorithm). Binary encoding can also be useful, but only when the methods mentioned above cannot be used.


Asunto(s)
Orden Génico , Filogenia , Algoritmos , Campanulaceae/clasificación , Campanulaceae/genética , Simulación por Computador , Bases de Datos Genéticas , Diatomeas/clasificación , Diatomeas/genética
17.
Mol Phylogenet Evol ; 69(3): 828-36, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23835079

RESUMEN

Our understanding of processes that led to biogeographic disjunct patterns of plant lineages in Macaronesia, North Africa and Socotra remains poor. Here, we study a group of Campanula species distributed across these areas integrating morphological and reproductive traits with phylogenetic and phylogeographic data based on the obtention of sequences for 4 highly variable cpDNA regions and AFLP data. The phylogeny obtained shows a sister relationship between Campanula jacobaea (endemic to Cape Verde Islands) and C. balfourii (endemic to Socotra), thus revealing a striking disjunct pattern (8300 km). These species diverged around 1.0 Mya; AFLP and haplotype data suggest that no genetic interchange has occurred since then. Their closest taxon, C. hypocrateriformis, is endemic to SW Morocco. The archipelagos of Macaronesia and Socotra have probably acted as refugia for North-African species, leading to speciation through isolation. Although C. balfourii has a restricted distribution, its genetic variability suggests that its populations have suffered no bottlenecks. C. jacobaea is also genetically rich and its distribution across Cape Verde Islands seems to have been influenced by the NE-SW trade winds, which may also have favoured the admixture found among the populations of the three southern islands. Floral features of the morphologically hypervariable C. jacobaea were also measured to assess whether the taxon C. bravensis, described for some of the southeast populations of C. jacobaea, corresponds to a different evolutionary entity. We show that morphological variation in C. jacobaea does not correspond to any genetic or geographic group.


Asunto(s)
Campanulaceae/clasificación , Especiación Genética , Filogenia , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Cabo Verde , Campanulaceae/anatomía & histología , Campanulaceae/genética , ADN de Cloroplastos/genética , ADN de Plantas/genética , Flores/anatomía & histología , Genética de Población , Haplotipos , Modelos Genéticos , Marruecos , Filogeografía , Análisis de Secuencia de ADN
18.
Mol Phylogenet Evol ; 69(3): 634-52, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23891952

RESUMEN

Phyteuma is a chromosomally and ecologically diverse vascular plant genus and constitutes an excellent system for studying both the role of chromosomal change for species diversification and the evolution of high-mountain biota. This kind of research is, however, hampered by the lack of a sound phylogenetic framework exacerbated by the notoriously low predictive power of traditional taxonomy with respect to phylogenetic relationships in Campanulaceae. Based on a comprehensive taxon sampling and analyses of nuclear and plastid sequence and AFLP fingerprint data, Phyteuma is confirmed as a monophyletic group sister to the monotypic Physoplexis, which is in line with their peculiar flower morphologies. Within Phyteuma two clades, largely corresponding to previously recognized sections, are consistently found. The traditional circumscription of taxonomic series is largely rejected. Whereas distinctness of the currently recognized species is mostly corroborated, some interspecific relationships remain ambiguous due to incongruences between nuclear and plastid data. Major forces for diversification and evolution of Phyteuma are descending dysploidy (i.e., a decrease in chromosome base number) as well as allopatric and ecological differentiation within the Alps, the genus' center of species diversity.


Asunto(s)
Campanulaceae/clasificación , Cromosomas de las Plantas/genética , Evolución Molecular , Filogenia , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Teorema de Bayes , Campanulaceae/genética , Núcleo Celular/genética , ADN de Plantas/genética , Cariotipo , Funciones de Verosimilitud , Modelos Genéticos , Plastidios/genética , Análisis de Secuencia de ADN
19.
Syst Biol ; 62(5): 725-37, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23676760

RESUMEN

The growth of phylogenetic trees in scope and in size is promising from the standpoint of understanding a wide variety of evolutionary patterns and processes. With trees comprised of larger, older, and globally distributed clades, it is likely that the lability of a binary character will differ significantly among lineages, which could lead to errors in estimating transition rates and the associated inference of ancestral states. Here we develop and implement a new method for identifying different rates of evolution in a binary character along different branches of a phylogeny. We illustrate this approach by exploring the evolution of growth habit in Campanulidae, a flowering plant clade containing some 35,000 species. The distribution of woody versus herbaceous species calls into question the use of traditional models of binary character evolution. The recognition and accommodation of changes in the rate of growth form evolution in different lineages demonstrates, for the first time, a robust picture of growth form evolution across a very large, very old, and very widespread flowering plant clade.


Asunto(s)
Evolución Biológica , Campanulaceae/clasificación , Clasificación/métodos , Modelos Biológicos , Biodiversidad , Campanulaceae/anatomía & histología , Simulación por Computador , Filogenia , Tiempo
20.
Mol Phylogenet Evol ; 68(3): 482-97, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23669010

RESUMEN

Cyananthus (Campanulaceae) is a small genus consisting of ca. 20 species endemic to the Sino-Himalayan region. Based on phylogenetic analysis using nuclear ribosomal ITS and four plastid markers (matK, rbcL, psbA-trnH and trnG-S), our results strongly support the monophyly of Cyananthus and its close relationship with the Codonopsis clade of the platycodonoids. Three major clades are supported, corresponding to the three sections of the genus, with sect. Cyananthus, which mainly occurs in the Himalayas, being a sister to the clade comprising the other two sections (sect. Stenolobi and sect. Annui) distributed primarily in the Hengduan Mountain region. We also observed that Cyananthus exhibits variation in its sexual system, possessing both hermaphroditic and gynodioecious species. Character evolution analyses using Mesquite suggest that gynodioecy evolved from hermaphroditism only once in sect. Stenolobi, but that there is a reversal in C. formosus. Molecular dating and biogeographic analysis with LAGRANGE support dispersal from the Himalayas to the Hengduan Mountains during the early evolution of Cyananthus. The extensive uplift of the Qinghai-Tibetan Plateau and the Hengduan Mountains played an important role in the subsequent diversification of the genus.


Asunto(s)
Evolución Biológica , Campanulaceae/clasificación , Campanulaceae/genética , Filogenia , Filogeografía , Reproducción , Biodiversidad , ADN Espaciador Ribosómico/genética , Evolución Molecular , Fenotipo , Plastidios/genética
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