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Tavares MM, Ferro M, Leal BSS, Palma‐Silva C. Speciation with gene flow between two Neotropical sympatric species (
Pitcairnia
spp.: Bromeliaceae). Ecol Evol 2022; 12:e8834. [PMID: 35509614 PMCID: PMC9055293 DOI: 10.1002/ece3.8834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/23/2022] [Accepted: 03/29/2022] [Indexed: 11/10/2022] Open
Affiliation(s)
- Marília Manuppella Tavares
- Departamento de Biologia Vegetal Instituto de Biologia Universidade Estadual de Campinas Campinas Brazil
| | - Milene Ferro
- Departamento de Biologia Geral e Aplicada Universidade Estadual Paulista Rio Claro Brazil
| | - Bárbara Simões Santos Leal
- Departamento de Biologia Vegetal Instituto de Biologia Universidade Estadual de Campinas Campinas Brazil
| | - Clarisse Palma‐Silva
- Departamento de Biologia Vegetal Instituto de Biologia Universidade Estadual de Campinas Campinas Brazil
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2
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Orsucci M, Sicard A. Flower evolution in the presence of heterospecific gene flow and its contribution to lineage divergence. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:971-989. [PMID: 33537708 DOI: 10.1093/jxb/eraa549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
The success of species depends on their ability to exploit ecological resources in order to optimize their reproduction. However, species are not usually found within single-species ecosystems but in complex communities. Because of their genetic relatedness, closely related lineages tend to cluster within the same ecosystem, rely on the same resources, and be phenotypically similar. In sympatry, they will therefore compete for the same resources and, in the case of flowering plants, exchange their genes through heterospecific pollen transfer. These interactions, nevertheless, pose significant challenges to species co-existence because they can lead to resource limitation and reproductive interference. In such cases, divergent selective pressures on floral traits will favour genotypes that isolate or desynchronize the reproduction of sympatric lineages. The resulting displacement of reproductive characters will, in turn, lead to pre-mating isolation and promote intraspecific divergence, thus initiating or reinforcing the speciation process. In this review, we discuss the current theoretical and empirical knowledge on the influence of heterospecific pollen transfer on flower evolution, highlighting its potential to uncover the ecological and genomic constraints shaping the speciation process.
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Affiliation(s)
- Marion Orsucci
- Department of Plant Biology, Swedish University of Agricultural, Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Adrien Sicard
- Department of Plant Biology, Swedish University of Agricultural, Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
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From micro- to macroevolution: insights from a Neotropical bromeliad with high population genetic structure adapted to rock outcrops. Heredity (Edinb) 2020; 125:353-370. [PMID: 32681156 DOI: 10.1038/s41437-020-0342-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/03/2020] [Accepted: 07/07/2020] [Indexed: 12/15/2022] Open
Abstract
Geographic isolation and reduced population sizes can lead to local extinction, low efficacy of selection and decreased speciation. However, population differentiation is an essential step of biological diversification. In allopatric speciation, geographically isolated populations differentiate and persist until the evolution of reproductive isolation and ecological divergence completes the speciation process. Pitcairnia flammea allows us to study the evolutionary consequences of habitat fragmentation on naturally disjoint rock-outcrop species from the Brazilian Atlantic Rainforest (BAF). Our main results showed low-to-moderate genetic diversity within populations, and deep population structuring caused by limited gene flow, low connectivity, genetic drift and inbreeding of long-term isolation and persistence of rock-outcrop populations throughout Quaternary climatic oscillations. Bayesian phylogenetic and model-based clustering analyses found no clear northern and southern phylogeographic structure commonly reported for many BAF organisms. Although we found two main lineages diverging by ~2 Mya during the early Pleistocene, species' delimitation analysis assigned most of the populations as independent evolving entities, suggesting an important role of disjoint rock outcrops in promoting high endemism in this rich biome. Lastly, we detected limited gene flow in sympatric populations although some hybridization and introgression were observed, suggesting a continuous speciation process in this species complex. Our data not only inform us about the extensive differentiation and limited gene flow found among Pitcairnia flammea species complex, but they also contain information about the mechanisms that shape the genetic architecture of small and fragmented populations of isolated rock outcrop of recently radiated plants.
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Colicchio J, Monnahan PJ, Wessinger CA, Brown K, Kern JR, Kelly JK. Individualized mating system estimation using genomic data. Mol Ecol Resour 2019; 20:333-347. [DOI: 10.1111/1755-0998.13094] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/27/2019] [Accepted: 08/19/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Jack Colicchio
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence KS USA
| | - Patrick J. Monnahan
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence KS USA
| | - Carolyn A. Wessinger
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence KS USA
| | - Keely Brown
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence KS USA
| | - James Russell Kern
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence KS USA
| | - John K. Kelly
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence KS USA
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Aguilar-Rodríguez PA, Tschapka M, García-Franco JG, Krömer T, MacSwiney G MC. Bromeliads going batty: pollinator partitioning among sympatric chiropterophilous Bromeliaceae. AOB PLANTS 2019; 11:plz014. [PMID: 31186827 PMCID: PMC6537948 DOI: 10.1093/aobpla/plz014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 03/08/2019] [Indexed: 06/09/2023]
Abstract
Pollinators can be a limited resource and natural selection should favour differences in phenotypic characteristics to reduce competition among plants. Bats are important pollinators of many Neotropical plants, including the Bromeliaceae; however, the pre-pollination mechanisms for isolation among sympatric bat-pollinated bromeliads are unknown. Here, we studied the mechanisms for reproductive segregation between Pitcairnia recurvata, Pseudalcantarea viridiflora, Werauhia noctiflorens and W. nutans. The study was conducted at Los Tuxtlas Biosphere Reserve, in Veracruz, Mexico We carried out ex situ and in situ manual pollination treatments to determine the breeding system by assessing fruiting and seedling success and sampled bat visitors using mist-nets and infrared cameras. We determined the nocturnal nectar production pattern, estimating the energetic content of this reward. All four bromeliads are self-compatible, but only P. recurvata appears to require pollinators, because the physical separation between anthers and stigma prevents self-pollination, it is xenogamous and presents a strictly nocturnal anthesis. The bats Anoura geoffroyi, Glossophaga soricina and Hylonycteris underwoodi are probable pollinators of three of the studied bromeliads. We did not record any animal visiting the fourth species. The flowering season of each species is staggered throughout the year, with minimal overlap, and the floral morphology segregates the locations on the body of the bat where the pollen is deposited. The most abundant nectar per flower is provided by P. viridiflora, but P. recurvata offers the best reward per hectare, considering the density of flowering plants. Staggered flowering, different pollen deposition sites on the body of the pollinator and differences in the reward offered may have evolved to reduce the competitive costs of sharing pollinators while providing a constant supply of food to maintain a stable nectarivorous bat community.
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Affiliation(s)
- Pedro Adrián Aguilar-Rodríguez
- Centro de Investigaciones Tropicales, Universidad Veracruzana, José María Morelos, Col. Centro, C.P. Xalapa, Veracruz, México
- Department of Zoology, Tel Aviv University, Tel Aviv, Israel
| | - Marco Tschapka
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert Einstein Allee 11, D Ulm, Germany
- Smithsonian Tropical Research Institute, Balboa Ancón, Apartado, Panamá, Republica de Panamáa
| | - José G García-Franco
- Red de Ecología Funcional, Instituto de Ecología, A.C., Carretera Antigua a Coatepec No. 351, El Haya, C.P. Xalapa, Veracruz, México
| | - Thorsten Krömer
- Centro de Investigaciones Tropicales, Universidad Veracruzana, José María Morelos, Col. Centro, C.P. Xalapa, Veracruz, México
| | - M Cristina MacSwiney G
- Centro de Investigaciones Tropicales, Universidad Veracruzana, José María Morelos, Col. Centro, C.P. Xalapa, Veracruz, México
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Mota MR, Pinheiro F, Leal BSS, Wendt T, Palma-Silva C. The role of hybridization and introgression in maintaining species integrity and cohesion in naturally isolated inselberg bromeliad populations. PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21:122-132. [PMID: 30195257 DOI: 10.1111/plb.12909] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 09/06/2018] [Indexed: 05/02/2023]
Abstract
Hybridization is a widespread phenomenon present in numerous lineages across the tree of life. Its evolutionary consequences range from effects on the origin and maintenance, to the loss of biodiversity. We studied genetic diversity and intra- and interspecific gene flow between two sympatric populations of closely-related species, Pitcairnia flammea and P. corcovadensis (Bromeliaceae), which are adapted to naturally fragmented Neotropical inselbergs, based on nuclear and plastidial DNA. Our main results indicate a strong reproductive isolation barrier, although low levels of interspecific gene flow were observed in both sympatric populations. The low rates of intraspecific gene flow observed for both P. corcovadensis and P. flammea populations corroborate the increasing body of evidence that inselberg bromeliad species are maintained as discrete evolutionary units despite the presence of low genetic connectivity. Nuclear patterns of genetic diversity and gene flow revealed that hybridization and introgression might not cause species extinction via genetic assimilation of the rare P. corcovadensis. In the face of reduced intraspecific gene exchange, hybridization and introgression may be important aspects of the Pitcairnia diversification process, with a positive evolutionary impact at the bromeliad community level, and thus contribute to increasing and maintaining genetic diversity in local isolated inselberg populations.
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Affiliation(s)
- M R Mota
- Departamento de Ecologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, Brazil
| | - F Pinheiro
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
| | - B S S Leal
- Departamento de Ecologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, Brazil
| | - T Wendt
- Departamento de Botânica, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - C Palma-Silva
- Departamento de Ecologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, Brazil
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
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Neri J, Wendt T, Palma-Silva C. Natural hybridization and genetic and morphological variation between two epiphytic bromeliads. AOB PLANTS 2018; 10:plx061. [PMID: 29308124 PMCID: PMC5751037 DOI: 10.1093/aobpla/plx061] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 11/22/2017] [Indexed: 05/18/2023]
Abstract
Reproductive isolation is of fundamental importance for maintaining species boundaries in sympatry. Here, we examine the genetic and morphological differences between two closely related bromeliad species: Vriesea simplex and Vriesea scalaris. Furthermore, we examined the occurrence of natural hybridization and discuss the action of reproductive isolation barriers. Nuclear genomic admixture suggests hybridization in sympatric populations, although interspecific gene flow is low among species in all sympatric zones (Nem < 0.5). Thus, morphological and genetic divergence (10.99 %) between species can be maintained despite ongoing natural hybridization. Cross-evaluation of our genetic and morphological data suggests that species integrity is maintained by the simultaneous action of multiple barriers, such as divergent reproductive systems among species, differences in floral traits and low hybrid seed viability.
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Affiliation(s)
- Jordana Neri
- Programa de Pós Graduação em Botânica, Departamento de Botânica, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, São Cristóvão, Rio de Janeiro, RJ, Brazil
| | - Tânia Wendt
- Departamento de Botânica, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Clarisse Palma-Silva
- Programa de Pós Graduação em Ecologia, Departamento de Ecologia – Universidade Estadual Paulista Julio Mesquita Filho, Rio Claro, SP, Brazil
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Pinheiro F, Zanfra de Melo E Gouveia TM, Cozzolino S, Cafasso D, Cardoso-Gustavson P, Suzuki RM, Palma-Silva C. Strong but permeable barriers to gene exchange between sister species of Epidendrum. AMERICAN JOURNAL OF BOTANY 2016; 103:1472-1482. [PMID: 27519428 DOI: 10.3732/ajb.1600064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/08/2016] [Indexed: 06/06/2023]
Abstract
PREMISE OF THE STUDY The investigation of reproductive barriers between sister species can provide insights into how new lineages arise, and how species integrity is maintained in the face of interspecific gene flow. Different pre- and postzygotic barriers can limit interspecific gene exchange in sympatric populations, and different sources of evidence are often required to investigate the role of multiple reproductive isolation (RI) mechanisms. METHODS We tested the hypothesis of hybridization and potential introgression between Epidendrum secundum and Epidendrum xanthinum, two Neotropical food-deceptive orchid species, using nuclear and plastid microsatellites, experimental crosses, pollen tube growth observations, and genome size estimates. KEY RESULTS A large number of hybrids between E. secundum and E. xanthinum were detected, suggesting weak premating barriers. The low fertility of hybrid plants and the absence of haplotype sharing between parental species indicated strong postmating barriers, reducing interspecific gene exchange and the development of advanced generation hybrids. Despite the strength of reproductive barriers, fertile seeds were produced in some backcrossing experiments, and the existence of interspecific gene exchange could not be excluded. CONCLUSIONS Strong but permeable barriers were found between E. secundum and E. xanthinum. Indeed, haplotype sharing was not detected between parental species, suggesting that introgression is limited by a combination of genic incompatibilities, including negative cytonuclear interactions. Most taxonomic uncertainties in this group were potentially influenced by incomplete RI barriers between species, which mainly occurred sympatrically.
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Affiliation(s)
- Fábio Pinheiro
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas 13083-862, Campinas, SP, Brazil Instituto de Botânica, Núcleo de Pesquisa do Orquidário do Estado04301-902, São Paulo, SP, Brazil
| | | | - Salvatore Cozzolino
- Dipartimento di Biologia, Complesso Universitario di Monte S. Ângelo, Università degli Studidi Napoli Federico II 80100 Napoli, Italy Institute for Sustenible Plant Protection, Consiglio Nazionale delle Ricerche, Via Madonna del Piano 10, I-50019 Sesto Fiorentino (FI), Italy
| | - Donata Cafasso
- Dipartimento di Biologia, Complesso Universitario di Monte S. Ângelo, Università degli Studidi Napoli Federico II 80100 Napoli, Italy
| | | | - Rogério Mamoru Suzuki
- Instituto de Botânica, Núcleo de Pesquisa do Orquidário do Estado04301-902, São Paulo, SP, Brazil
| | - Clarisse Palma-Silva
- Departamento de Ecologia, Universidade Estadual Paulista 13506-900, Rio Claro, SP, Brazil
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Castillo DM, Gibson AK, Moyle LC. Assortative mating and self-fertilization differ in their contributions to reinforcement, cascade speciation, and diversification. Curr Zool 2016; 62:169-181. [PMID: 29491904 PMCID: PMC5804227 DOI: 10.1093/cz/zow004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 01/07/2016] [Indexed: 11/14/2022] Open
Abstract
Cascade speciation and reinforcement can evolve rapidly when traits are pleiotropic and act as both signal/cue in nonrandom mating. Here, we examine the contribution of two key traits-assortative mating and self-fertilization-to reinforcement and (by extension) cascade speciation. First, using a population genetic model of reinforcement we find that both assortative mating and self-fertilization can make independent contributions to increased reproductive isolation, consistent with reinforcement. Self-fertilization primarily evolves due to its 2-fold transmission advantage when inbreeding depression (d) is lower (d < 0.45) but evolves as a function of the cost of hybridization under higher inbreeding depression (0.45 < d < 0.48). When both traits can evolve simultaneously, increased self-fertilization often prohibits the evolution of assortative mating. We infer that, under specific conditions, mating system transitions are more likely to lead to increased reproductive isolation and initiate cascade speciation, than assortative mating. Based on the results of our simulations, we hypothesized that transitions to self-fertilization could contribute to clade-wide diversification if reinforcement or cascade speciation is common. We tested this hypothesis with comparative data from two different groups. Consistent with our hypothesis, there was a trend towards uniparental reproduction being associated with increased diversification rate in the Nematode phylum. For the plant genus Mimulus, however, self-fertilization was associated with reduced diversification. Reinforcement driving speciation via transitions to self-fertilization might be short lived or unsustainable across macroevolutionary scales in some systems (some plants), but not others (such as nematodes), potentially due to differences in susceptibility to inbreeding depression and/or the ability to transition between reproductive modes.
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Affiliation(s)
- Dean M. Castillo
- Department of Biology, 1001 East Third Street, Indiana University, Bloomington, IN 47405, USA
| | - Amanda K. Gibson
- Department of Biology, 1001 East Third Street, Indiana University, Bloomington, IN 47405, USA
| | - Leonie C. Moyle
- Department of Biology, 1001 East Third Street, Indiana University, Bloomington, IN 47405, USA
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Palma-Silva C, Ferro M, Bacci M, Turchetto-Zolet AC. De novo assembly and characterization of leaf and floral transcriptomes of the hybridizing bromeliad species (Pitcairnia spp.) adapted to Neotropical Inselbergs. Mol Ecol Resour 2016; 16:1012-22. [PMID: 26849180 DOI: 10.1111/1755-0998.12504] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 12/17/2015] [Accepted: 12/22/2015] [Indexed: 02/06/2023]
Abstract
We present the leaf and floral transcriptomes of two hybridizing bromeliad species that differ in their major pollinator systems. Here we identified candidate genes responsible for pollinator attraction and reproductive isolation in these two species. We searched for candidate genes involved in floral traits, such as colour. Approximately 34 Gbp of cDNA sequence data were produced from both tissues and species, resulting in a total of 424 506 914 raw reads. The de novo-assembled transcriptomes consisted of a total of 263 955 contigs, further clustered into 110 977 unigenes. Over 58% of the unigenes were functionally annotated and assigned to one or more Gene Ontology terms. The transcriptomes revealed 144 unique transcripts that encode key enzymes in the flavonoid and anthocyanin biosynthesis pathways. The domain/family annotation and phylogenetic analysis allowed us to infer, by homology, potential functions of the genes encoding MYB, HD-ZIP and bZIP-HY5 transcription factors, as well as WD40 protein, which may be involved in anthocyanin and flavonoid regulation in these species. These candidate genes are associated with natural regulation in flower colour in other plant species and will facilitate future studies aimed at elucidating the molecular basis of adaptive differentiation and the evolution of mechanisms of pollinator-mediated reproductive isolation in these two bromeliads. In addition, we identified a total of 49 439 microsatellite loci. These resources will assist future research into adaptation and speciation events in bromeliad species, thus providing a starting point for investigation of the molecular mechanisms of the traits responsible for their reproductive isolation.
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Affiliation(s)
- C Palma-Silva
- Departamento de Ecologia, Programa de Pós-graduação em Ecologia e Biodiversidade, Instituto de Biociências, Universidade Estadual Paulista Julio Mesquita Filho, 13506-900, Rio Claro, SP, Brazil
| | - M Ferro
- Centro de Estudos de Insetos Sociais, Instituto de Biociências, Universidade Estadual Paulista Julio Mesquita Filho, 13506-900, Rio Claro, SP, Brazil
| | - M Bacci
- Centro de Estudos de Insetos Sociais, Instituto de Biociências, Universidade Estadual Paulista Julio Mesquita Filho, 13506-900, Rio Claro, SP, Brazil
| | - A C Turchetto-Zolet
- Departamento de Genética, Programa de Pós-graduação em Genética e Biologia Molecular, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, 91501-970, Porto Alegre, RS, Brazil
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Twyford AD, Kidner CA, Ennos RA. Maintenance of species boundaries in a Neotropical radiation of Begonia. Mol Ecol 2016; 24:4982-93. [PMID: 26301313 PMCID: PMC4600226 DOI: 10.1111/mec.13355] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 08/18/2015] [Accepted: 08/19/2015] [Indexed: 01/04/2023]
Abstract
A major goal of evolutionary biology is to determine the mechanisms generating biodiversity. In Begonia, one of the largest plant genera (1900+ species), it has been postulated that the high number of endemic species is a by-product of low gene flow among populations, which predisposes the group to speciation. However, this model of divergence requires that reproductive barriers accumulate rapidly among diverging species that overlap in their geographic ranges, otherwise speciation will be opposed by homogenizing gene flow in zones of secondary contact. Here, we test the outcomes of secondary contact in Begonia by genotyping multiple sympatric sites with 12 nuclear and seven plastid loci. We show that three sites of secondary contact between B. heracleifolia and B. nelumbiifolia are highly structured, mostly containing parental genotypes, with few F1 hybrids. A sympatric site between B. heracleifolia and B. sericoneura contains a higher proportion of F1s, but little evidence of introgression. The lack of later-generation hybrids contrasts with that documented in many other plant taxa, where introgression is extensive. Our results, in conjunction with previous genetic work, show that Begonia demonstrate properties making them exceptionally prone to speciation, at multiple stages along the divergence continuum. Not only are populations weakly connected by gene flow, promoting allopatric speciation, but species often show strong reproductive barriers in secondary contact. Whether similar mechanisms contribute to diversification in other large genera remains to be tested.
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Affiliation(s)
- Alex D Twyford
- Ashworth Laboratories, Institute of Evolutionary Biology, The University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK.,Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh, EH3 5LR, UK.,Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JH, UK
| | - Catherine A Kidner
- Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh, EH3 5LR, UK.,Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JH, UK
| | - Richard A Ennos
- Ashworth Laboratories, Institute of Evolutionary Biology, The University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK
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