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Kazama Y, Kitoh M, Kobayashi T, Ishii K, Krasovec M, Yasui Y, Abe T, Kawano S, Filatov DA. A CLAVATA3-like Gene Acts as a Gynoecium Suppression Function in White Campion. Mol Biol Evol 2022; 39:msac195. [PMID: 36166820 PMCID: PMC9550985 DOI: 10.1093/molbev/msac195] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
How do separate sexes originate and evolve? Plants provide many opportunities to address this question as they have diverse mating systems and separate sexes (dioecy) that evolved many times independently. The classic "two-factor" model for evolution of separate sexes proposes that males and females can evolve from hermaphrodites via the spread of male and female sterility mutations that turn hermaphrodites into females and males, respectively. This widely accepted model was inspired by early genetic work in dioecious white campion (Silene latifolia) that revealed the presence of two sex-determining factors on the Y-chromosome, though the actual genes remained unknown. Here, we report identification and functional analysis of the putative sex-determining gene in S. latifolia, corresponding to the gynoecium suppression factor (GSF). We demonstrate that GSF likely corresponds to a Y-linked CLV3-like gene that is specifically expressed in early male flower buds and encodes the protein that suppresses gynoecium development in S. latifolia. Interestingly, GSFY has a dysfunctional X-linked homolog (GSFX) and their synonymous divergence (dS = 17.9%) is consistent with the age of sex chromosomes in this species. We propose that female development in S. latifolia is controlled via the WUSCHEL-CLAVATA feedback loop, with the X-linked WUSCHEL-like and Y-linked CLV3-like genes, respectively. Evolution of dioecy in the S. latifolia ancestor likely involved inclusion of ancestral GSFY into the nonrecombining region on the nascent Y-chromosome and GSFX loss of function, which resulted in disbalance of the WUSCHEL-CLAVATA feedback loop between the sexes and ensured gynoecium suppression in males.
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Affiliation(s)
- Yusuke Kazama
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Japan
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Moe Kitoh
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Japan
| | - Taiki Kobayashi
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Japan
| | - Kotaro Ishii
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Marc Krasovec
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, 66650 Banyuls-sur-Mer, France
| | - Yasuo Yasui
- Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Tomoko Abe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Shigeyuki Kawano
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, FSB-601, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
- Future Center Initiative, The University of Tokyo, 178-4-4 Wakashiba, Kashiwa, Chiba 277-0871, Japan
| | - Dmitry A Filatov
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
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Carley LN, Morris WF, Walsh R, Riebe D, Mitchell‐Olds T. Are genetic variation and demographic performance linked? Evol Appl 2022; 15:1888-1906. [DOI: 10.1111/eva.13487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 09/12/2022] [Indexed: 12/13/2022] Open
Affiliation(s)
- Lauren N. Carley
- University Program in Ecology Duke University Durham North Carolina USA
- Biology Department Duke University Durham North Carolina USA
- Department of Plant and Microbial Biology University of Minnesota Twin Cities St. Paul Minnesota USA
| | | | - Roberta Walsh
- Division of Biological Sciences University of Montana Missoula Montana USA
| | - Donna Riebe
- Division of Biological Sciences University of Montana Missoula Montana USA
| | - Tom Mitchell‐Olds
- Biology Department Duke University Durham North Carolina USA
- Division of Biological Sciences University of Montana Missoula Montana USA
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Cohen O, Ram Y, Hadany L, Gafny S, Geffen E. Annual climatic fluctuations and short-term genetic variation in the eastern spadefoot toad. Sci Rep 2021; 11:13514. [PMID: 34188104 PMCID: PMC8241830 DOI: 10.1038/s41598-021-92696-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 06/10/2021] [Indexed: 11/15/2022] Open
Abstract
In addition to variations on the spatial scale, short- and long-term temporal variations, too, can impose intense selection on the overall genetic diversity and composition of a population. We hypothesized that the allelic composition in populations of the eastern spadefoot toad (Pelobates syriacus) would change among successive years in accordance with the short-term changes in environmental conditions. Surprisingly, the effect of short-term climate fluctuations on genetic composition have rarely been addressed in the literature, and to our knowledge the effect of annual climatic fluctuations have not been considered meaningful. Our findings show that climatic variation among successive years, primarily the amount of rainfall and rainy days, can significantly alter both microsatellite allelic composition and diversity. We suggest that environmental (i.e. fluctuating) selection is differential across the globe, and that its intensity is expected to be greatest in regions where short-term climatic conditions are least stable.
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Affiliation(s)
- Orly Cohen
- School of Zoology, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Yoav Ram
- School of Zoology, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Lilach Hadany
- School of Plant Sciences and Food Security, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Sarig Gafny
- Faculty of Marine Sciences, Ruppin Academic Center, 40297, Michmoret, Israel
| | - Eli Geffen
- School of Zoology, Tel Aviv University, 69978, Tel Aviv, Israel.
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Zhou J, Dudash MR, Zimmer EA, Fenster CB. Comparison of population genetic structures of the plant Silene stellata and its obligate pollinating seed predator moth Hadena ectypa. ANNALS OF BOTANY 2018; 122:593-603. [PMID: 29850821 PMCID: PMC6153480 DOI: 10.1093/aob/mcy091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 05/03/2018] [Indexed: 05/29/2023]
Abstract
BACKGROUND AND AIMS Population genetic structures and patterns of gene flow of interacting species provide important insights into the spatial scale of their interactions and the potential for local co-adaptation. We analysed the genetic structures of the plant Silene stellata and the nocturnal moth Hadena ectypa. Hadena ectypa acts as one of the important pollinators of S. stellata as well as being an obligate seed parasite on the plant. Although H. ectypa provides a substantial pollination service to S. stellata, this system is largely considered parasitic due to the severe seed predation by the Hadena larvae. Previous research on this system has found variable interaction outcomes across space, indicating the potential for a geographical selection mosaic. METHODS Using 11 microsatellite markers for S. stellata and nine markers for H. ectypa, we analysed the population genetic structure and the patterns and intensity of gene flow within and among three local populations in the Appalachians. KEY RESULTS We found no spatial genetic structure in the moth populations, while significant differentiation was detected among the local plant populations. Additionally, we observed that gene flow rates among H. ectypa populations were more uniform and that the mean gene flow rate in H. ectypa was twice as large as that in S. stellata. CONCLUSIONS Our results suggest that although the moths move frequently among populations, long-distance pollen carryover only happens occasionally. The difference in gene flow rates between S. stellata and H. ectypa could prevent strict local co-adaptation. Furthermore, higher gene flow rates in H. ectypa could also increase resistance of the local S. stellata populations to the parasitic effect of H. ectypa and therefore help to stabilize the Silene-Hadena interaction dynamics.
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Affiliation(s)
- Juannan Zhou
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Michele R Dudash
- Department of Natural Resource Management, South Dakota State University, Brookings, SD, USA
| | - Elizabeth A Zimmer
- Department of Botany, National Museum of Natural History, MRC 166, Smithsonian Institution, Washington, DC, USA
| | - Charles B Fenster
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD, USA
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Gentili R, Solari A, Diekmann M, Duprè C, Monti GS, Armiraglio S, Assini S, Citterio S. Genetic differentiation, local adaptation and phenotypic plasticity in fragmented populations of a rare forest herb. PeerJ 2018; 6:e4929. [PMID: 29915689 PMCID: PMC6004105 DOI: 10.7717/peerj.4929] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/18/2018] [Indexed: 12/04/2022] Open
Abstract
Background Due to habitat loss and fragmentation, numerous forest species are subject to severe population decline. Investigating variation in genetic diversity, phenotypic plasticity and local adaptation should be a prerequisite for implementing conservation actions. This study aimed to explore these aspects in ten fragmented populations of Physospermum cornubiense in view of translocation measures across its Italian range. Methods For each population we collected environmental data on landscape (habitat size, quality and fragmentation) and local conditions (slope, presence of alien species, incidence of the herbivorous insect Metcalfa pruinosa and soil parameters). We measured vegetative and reproductive traits in the field and analysed the genetic population structure using ISSR markers (STRUCTURE and AMOVA). We then estimated the neutral (FST) and quantitative (PST) genetic differentiation of populations. Results The populations exhibited moderate phenotypic variation. Population size (range: 16–655 individuals), number of flowering adults (range: 3–420 individuals) and inflorescence size (range: 5.0–8.4 cm) were positively related to Mg soil content. Populations’ gene diversity was moderate (Nei-H = 0.071–0.1316); STRUCTURE analysis identified five different clusters and three main geographic groups: upper, lower, and Apennine/Western Po plain. Fragmentation did not have an influence on the local adaptation of populations, which for all measured traits showed PST < FST, indicating convergent selection. Discussion The variation of phenotypic traits across sites was attributed to plastic response rather than local adaptation. Plant translocation from suitable source populations to endangered ones should particularly take into account provenance according to identified genetic clusters and specific soil factors.
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Affiliation(s)
- Rodolfo Gentili
- Department of Earth and Environmental Sciences, University of Milan-Bicocca, Milan, Italy
| | - Aldo Solari
- Department of Economics, Management and Statistics, University of Milan-Bicocca, Milan, Italy
| | | | - Cecilia Duprè
- Institute of Ecology, University of Bremen, Bremen, Germany
| | - Gianna Serafina Monti
- Department of Economics, Management and Statistics, University of Milan-Bicocca, Milan, Italy
| | | | - Silvia Assini
- Department of Earth and Environmental Sciences, University of Pavia, Pavia, Italy
| | - Sandra Citterio
- Department of Earth and Environmental Sciences, University of Milan-Bicocca, Milan, Italy
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Krasovec M, Chester M, Ridout K, Filatov DA. The Mutation Rate and the Age of the Sex Chromosomes in Silene latifolia. Curr Biol 2018; 28:1832-1838.e4. [PMID: 29804812 DOI: 10.1016/j.cub.2018.04.069] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 04/12/2018] [Accepted: 04/19/2018] [Indexed: 12/15/2022]
Abstract
Many aspects of sex chromosome evolution are common to both plants and animals [1], but the process of Y chromosome degeneration, where genes on the Y become non-functional over time, may be much slower in plants due to purifying selection against deleterious mutations in the haploid gametophyte [2, 3]. Testing for differences in Y degeneration between the kingdoms has been hindered by the absence of accurate age estimates for plant sex chromosomes. Here, we used genome resequencing to estimate the spontaneous mutation rate and the age of the sex chromosomes in white campion (Silene latifolia). Screening of single nucleotide polymorphisms (SNPs) in parents and 10 F1 progeny identified 39 de novo mutations and yielded a rate of 7.31 × 10-9 (95% confidence interval: 5.20 × 10-9 - 8.00 × 10-9) mutations per site per haploid genome per generation. Applying this mutation rate to the synonymous divergence between homologous X- and Y-linked genes (gametologs) gave age estimates of 11.00 and 6.32 million years for the old and young strata, respectively. Based on SNP segregation patterns, we inferred which genes were Y-linked and found that at least 47% are already dysfunctional. Applying our new estimates for the age of the sex chromosomes indicates that the rate of Y degeneration in S. latifolia is nearly 2-fold slower when compared to animal sex chromosomes of a similar age. Our revised estimates support Y degeneration taking place more slowly in plants, a discrepancy that may be explained by differences in the life cycles of animals and plants.
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Affiliation(s)
- Marc Krasovec
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
| | - Michael Chester
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
| | - Kate Ridout
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
| | - Dmitry A Filatov
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK.
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7
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Antonova EV, Korchagina OS. Microsatellite loci variability in the ural population of Silene latifolia (caryophyllaceae). BIOL BULL+ 2017. [DOI: 10.1134/s1062359017050028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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8
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Husemann M, Cousseau L, Callens T, Matthysen E, Vangestel C, Hallmann C, Lens L. Post-fragmentation population structure in a cooperative breeding Afrotropical cloud forest bird: emergence of a source-sink population network. Mol Ecol 2015; 24:1172-87. [PMID: 25677704 DOI: 10.1111/mec.13105] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/29/2015] [Accepted: 02/04/2015] [Indexed: 11/27/2022]
Abstract
The impact of demographic parameters on the genetic population structure and viability of organisms is a long-standing issue in the study of fragmented populations. Demographic and genetic tools are now readily available to estimate census and effective population sizes and migration and gene flow rates with increasing precision. Here we analysed the demography and genetic population structure over a recent 15-year time span in five remnant populations of Cabanis's greenbul (Phyllastrephus cabanisi), a cooperative breeding bird in a severely fragmented cloud forest habitat. Contrary to our expectation, genetic admixture and effective population sizes slightly increased, rather than decreased between our two sampling periods. In spite of small effective population sizes in tiny forest remnants, none of the populations showed evidence of a recent population bottleneck. Approximate Bayesian modelling, however, suggested that differentiation of the populations coincided at least partially with an episode of habitat fragmentation. The ratio of meta-Ne to meta-Nc was relatively low for birds, which is expected for cooperative breeding species, while Ne /Nc ratios strongly varied among local populations. While the overall trend of increasing population sizes and genetic admixture may suggest that Cabanis's greenbuls increasingly cope with fragmentation, the time period over which these trends were documented is rather short relative to the average longevity of tropical species. Furthermore, the critically low Nc in the small forest remnants keep the species prone to demographic and environmental stochasticity, and it remains open if, and to what extent, its cooperative breeding behaviour helps to buffer such effects.
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Affiliation(s)
- M Husemann
- General Zoology, Institute of Biology, Martin-Luther University Halle-Wittenberg, Halle (Saale), Germany
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9
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Determinants of genetic structure in a nonequilibrium metapopulation of the plant Silene latifolia. PLoS One 2014; 9:e104575. [PMID: 25198341 PMCID: PMC4157773 DOI: 10.1371/journal.pone.0104575] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 07/15/2014] [Indexed: 11/19/2022] Open
Abstract
Population genetic differentiation will be influenced by the demographic history of populations, opportunities for migration among neighboring demes and founder effects associated with repeated extinction and recolonization. In natural populations, these factors are expected to interact with each other and their magnitudes will vary depending on the spatial distribution and age structure of local demes. Although each of these effects has been individually identified as important in structuring genetic variance, their relative magnitude is seldom estimated in nature. We conducted a population genetic analysis in a metapopulation of the angiosperm, Silene latifolia, from which we had more than 20 years of data on the spatial distribution, demographic history, and extinction and colonization of demes. We used hierarchical Bayesian methods to disentangle which features of the populations contributed to among population variation in allele frequencies, including the magnitude and direction of their effects. We show that population age, long-term size and degree of connectivity all combine to affect the distribution of genetic variance; small, recently-founded, isolated populations contributed most to increase FST in the metapopulation. However, the effects of population size and population age are best understood as being modulated through the effects of connectivity to other extant populations, i.e. FST diminishes as populations age, but at a rate that depends how isolated the population is. These spatial and temporal correlates of population structure give insight into how migration, founder effect and within-deme genetic drift have combined to enhance and restrict genetic divergence in a natural metapopulation.
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Magalhaes IS, Bernasconi G. Phenotypic divergence and inter-specific trait correlation in a plant-pollinator/seed predator mutualism. Evol Ecol 2014. [DOI: 10.1007/s10682-014-9713-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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MAGALHAES ISABELS, GLEISER GABRIELA, LABOUCHE ANNEMARIE, BERNASCONI GIORGINA. Comparative population genetic structure in a plant-pollinator/seed predator system. Mol Ecol 2011; 20:4618-30. [DOI: 10.1111/j.1365-294x.2011.05296.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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GOMAA NASRH, MONTESINOS-NAVARRO ALICIA, ALONSO-BLANCO CARLOS, PICÓ FXAVIER. Temporal variation in genetic diversity and effective population size of Mediterranean and subalpine Arabidopsis thaliana populations. Mol Ecol 2011; 20:3540-54. [DOI: 10.1111/j.1365-294x.2011.05193.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Austerlitz F, Gleiser G, Teixeira S, Bernasconi G. The effects of inbreeding, genetic dissimilarity and phenotype on male reproductive success in a dioecious plant. Proc Biol Sci 2011; 279:91-100. [PMID: 21561968 DOI: 10.1098/rspb.2011.0652] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pollen fate can strongly affect the genetic structure of populations with restricted gene flow and significant inbreeding risk. We established an experimental population of inbred and outbred Silene latifolia plants to evaluate the effects of (i) inbreeding depression, (ii) phenotypic variation and (iii) relatedness between mates on male fitness under natural pollination. Paternity analysis revealed that outbred males sired significantly more offspring than inbred males. Independently of the effects of inbreeding, male fitness depended on several male traits, including a sexually dimorphic (flower number) and a gametophytic trait (in vitro pollen germination rate). In addition, full-sib matings were less frequent than randomly expected. Thus, inbreeding, phenotype and genetic dissimilarity simultaneously affect male fitness in this animal-pollinated plant. While inbreeding depression might threaten population persistence, the deficiency of effective matings between sibs and the higher fitness of outbred males will reduce its occurrence and counter genetic erosion.
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Affiliation(s)
- Frédéric Austerlitz
- Laboratoire Ecologie, Systématique et Evolution, UMR CNRS 8079, Université, Paris-Sud, 91405 Orsay Cedex, France
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14
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Affiliation(s)
- S R Keller
- Department of Biology, University of Virginia, Charlottesville, VA 22904-4328, USA.
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15
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HOEBE PN, STIFT M, TEDDER A, MABLE BK. Multiple losses of self-incompatibility in North-AmericanArabidopsis lyrata?: Phylogeographic context and population genetic consequences. Mol Ecol 2009; 18:4924-39. [DOI: 10.1111/j.1365-294x.2009.04400.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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16
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Labouche AM, Bernasconi G. Male moths provide pollination benefits in theSilene latifolia-Hadena bicrurisnursery pollination system. Funct Ecol 2009. [DOI: 10.1111/j.1365-2435.2009.01658.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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17
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Zartman CE, Shaw AJ. Metapopulation extinction thresholds in rain forest remnants. Am Nat 2006; 167:177-89. [PMID: 16670979 DOI: 10.1086/499376] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Accepted: 10/06/2005] [Indexed: 11/03/2022]
Abstract
Although habitat fragmentation is a major threat to global biodiversity, the demographic mechanisms underlying species loss from tropical forest remnants remain largely unexplored. In particular, no studies at the landscape scale have quantified fragmentation's impacts on colonization, extinction, and local population growth simultaneously. In central Amazonia, we conducted a multiyear demographic census of 292 populations of two leaf-inhabiting (i.e., epiphyllous) bryophyte species transplanted from continuous forest into a network of 10 study sites ranging from 1, 10, and 100 to > 10,000 ha in size. All populations experienced significantly positive local growth (lambda > 1) and a nearly constant per-generational extinction probability (15%). However, experimental leaf patches in reserves of > or = 100 ha experienced nearly double (48%) the colonization probability observed in small reserves (27%), suggesting that the proximate cause of epiphyll species loss in small fragments (< or = 10 ha) is reduced colonization. Nonetheless, populations of small fragments exhibit rates of colonization above patch extinction, positive local growth, and low temporal variation, which are features that should theoretically reduce the probability of extinction. This result suggests that for habitat-tracking metapopulations subject to frequent and stochastic turnover events, including epiphylls, colonization/extinction ratios must be maintained well above unity to ensure metapopulation persistence.
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Affiliation(s)
- Charles E Zartman
- Department of Biology, Duke University, Durham, North Carolina 27707, USA.
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Noel F, Porcher E, Moret J, Machon N. Connectivity, habitat heterogeneity, and population persistence in Ranunculus nodiflorus, an endangered species in France. THE NEW PHYTOLOGIST 2006; 169:71-83. [PMID: 16390420 DOI: 10.1111/j.1469-8137.2005.01572.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Here, we explore the role of habitat spatial structure in the maintenance of metapopulations of Ranunculus nodiflorus. This rare species grows in puddles that can be connected occasionally by flooded corridors. We monitored five locations in the Fontainebleau forest, France, since 2002 and recorded the presence of corridors among puddles and evaluated their impact on puddle demography and plant fitness. We showed that connections increased population size, by increasing both the number of puddles occupied by the species and the density of individuals within puddles, but seemed to have no direct influence on plant fitness. We found no evidence of a large persistent soil seed bank. Natural corridors are likely to decrease the extinction probability of the populations, most probably by allowing recolonization of empty puddles after extinctions. Therefore, the preservation of corridors appears crucial for the conservation of R. nodiflorus in its natural habitat.
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Affiliation(s)
- Florence Noel
- Conservatoire Botanique National du Bassin Parisien, Muséum National d'Histoire Naturelle, 61 rue Buffon, F-75005 Paris, France.
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