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Dong CM, Rolón BA, Sullivan JK, Tataru D, Deleon M, Dennis R, Dutton S, Machado Perez FJ, Montano L, Ferris KG. Short-term fluctuating and long-term divergent selection on sympatric Monkeyflowers: insights from decade-spanning reciprocal transplants. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.26.600870. [PMID: 38979251 PMCID: PMC11230446 DOI: 10.1101/2024.06.26.600870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Sympatric species are often locally adapted to distinct microhabitats. However, temporal variation may cause local maladaptation and species boundary breakdown, especially during extreme climatic events leading to episodic selection. Repeated reciprocal transplants can reveal the interplay between short and long-term patterns of natural selection. To examine evolutionary trajectories of sympatric Monkeyflowers adapted to different niches, Mimulus guttatus and M. laciniatus, we performed three replicated transplants and combined them with previous experiments to leverage a dataset of five transplants spanning 10 years. We performed phenotypic selection analyses on parents and hybrids in parental habitats in Yosemite NP, CA during years of drastically differing snowpack. If there is ecological isolation, then we predicted divergent phenotypic selection between habitats in line with species' differences and local adaptation. We found interannual fluctuations in phenotypic selection, often in unpredicted directions. However, a combined-year analysis detected longer-term divergent selection on flowering time, a key temporally isolating and adaptative trait, suggesting that selection may reinforce species boundaries despite short-term fluctuations. Finally, we found temporal variation in local adaptation with M. laciniatus locally adapted in low snowpack years, while an extremely high snowpack year contributed to average local maladaptation of M. guttatus.
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Affiliation(s)
- Caroline M Dong
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
- Grinnell College, Department of Biology, Grinnell, IA
| | - Bolívar Aponte Rolón
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
| | - Juj K Sullivan
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
| | - Diana Tataru
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
| | - Max Deleon
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
| | - Rachael Dennis
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
| | - Spencer Dutton
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
| | - Fidel J Machado Perez
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
- University of California Merced, Life and Environmental Sciences Department, Merced, CA
| | - Lissette Montano
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
| | - Kathleen G Ferris
- Tulane University, Department of Ecology and Evolutionary Biology, New Orleans, LA
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Shelton WR, Mitchell RJ, Christopher DA, Jack LP, Karron JD. Among-individual variation in flowering phenology affects flowering synchrony and mating opportunity. AMERICAN JOURNAL OF BOTANY 2024; 111:e16269. [PMID: 38126922 DOI: 10.1002/ajb2.16269] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 12/23/2023]
Abstract
PREMISE The timing and pattern of a plant's flowering can have important consequences for reproductive success. Variation in flowering phenology may influence the number of prospective mates, the risk of mating with lower quality individuals, and the likelihood of self-pollination. Here we use a common garden experiment to explore within- and among-population variation in phenology. Our work provides new insights into how flowering phenology shapes mating opportunity and flowering synchrony in a self-compatible perennial. METHODS To quantify variation in flowering phenology we raised progeny from nine populations of Mimulus ringens in a common garden. For each individual, we measured phenological traits including age at flowering onset, daily floral display size, total flower number, and flowering synchrony with other members of the population, and related these traits to mating opportunity. We also tested how individual flowering schedules influence the magnitude of synchrony. RESULTS Flowering phenology and synchrony varied substantially within and among populations. From day to day, plants often oscillated between large and small daily floral displays. Additionally, flowering schedules of individual plants strongly influenced flowering synchrony and, along with the number of flowering days, markedly affected plants' mating opportunity. CONCLUSIONS Phenological traits such as flowering synchrony can affect the quantity of mating opportunities and may be important targets of natural selection. Our results highlight the need for studies that quantify flowering patterns of individuals as well as populations.
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Affiliation(s)
- Wendy R Shelton
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
| | | | - Dorothy A Christopher
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
- Department of Biology, Western Connecticut State University, Danbury, Connecticut, 06810, USA
| | - Loretha P Jack
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
| | - Jeffrey D Karron
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
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3
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Bateman RM, Stott KM, Pearce DF. Trait analysis in a population of the Greater Butterfly-orchid observed through a 16-year period. FRONTIERS IN PLANT SCIENCE 2023; 14:1213250. [PMID: 37615028 PMCID: PMC10442717 DOI: 10.3389/fpls.2023.1213250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 07/05/2023] [Indexed: 08/25/2023]
Abstract
A large English population of the temperate tuberous Greater Butterfly-orchid, Platanthera chlorantha, was monitored through a 16-year period. Each June the number of flowering plants was counted and 60 flowering plants were measured in situ for four morphological traits, selected for both ease of measurement and their contrasting contributions to the life history of the species. Trait data were tested annually in pairwise combinations for individual plants, before mean values throughout the study period were regressed and cross-correlated against each other and against local data for four meteorological parameters. Labellar spur length proved to be more constrained than either flower number or stem height, and rarely yielded statistically significant correlations with other traits, whereas the three remaining traits reliably showed modest but significant correlations. Mean values and coefficients of variation differed only modestly among years and showed few of any meaningful trends. Spring rainfall and insolation had no detectable effect on traits of plants flowering that June; instead, they impacted on trait expression during the following year, presumably as a result of differential resourcing of replacement tubers formed during the previous year. High spring rainfall in year t-1 increased leaf area and stem height in year t, whereas the widely fluctuating number of flowering plants was highest in years immediately following those characterised by relatively dry and/or sunny springs. The "decision" to flower is taken during the previous summer, though it may be modified through winter/spring abortion of above-ground organs. The proportion of the population electing to flower is the only measured parameter that impacts significantly on annual reproductive output, emphasising the under-rated difficulty of evolving through directional selection. Any attempt to predict the behaviour of plant species in response to climate change must integrate information on demography with that on life history, habitat preference and intimate symbioses.
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Bateman RM, Rudall PJ. Morphological Continua Make Poor Species: Genus-Wide Morphometric Survey of the European Bee Orchids ( Ophrys L.). BIOLOGY 2023; 12:136. [PMID: 36671828 PMCID: PMC9855528 DOI: 10.3390/biology12010136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/03/2023] [Accepted: 01/09/2023] [Indexed: 01/17/2023]
Abstract
Despite (or perhaps because of) intensive multidisciplinary research, opinions on the optimal number of species recognised within the Eurasian orchid genus Ophrys range from nine to at least 400. The lower figure of nine macrospecies is based primarily on seeking small but reliable discontinuities in DNA 'barcode' regions, an approach subsequently reinforced and finessed via high-throughput sequencing studies. The upper figure of ca. 400 microspecies reflects the morphological authoritarianism of traditional taxonomy combined with belief in extreme pollinator specificity caused by reliance on pollination through pseudo-copulation, enacted by bees and wasps. Groupings of microspecies that are less inclusive than macrospecies are termed mesospecies. Herein, we present multivariate morphometric analyses based on 51 characters scored for 457 individual plants that together span the full morphological and molecular diversity within the genus Ophrys, encompassing 113 named microspecies that collectively represent all 29 mesospecies and all nine macrospecies. We critique our preferred morphometric approach of accumulating heterogeneous data and analysing them primarily using principal coordinates, noting that our conclusions would have been strengthened by even greater sampling and the inclusion of data describing pseudo-pheromone cocktails. Morphological variation within Ophrys proved to be exceptionally multidimensional, lacking strong directional trends. Multivariate clustering of plants according to prior taxonomy was typically weak, irrespective of whether it was assessed at the level of macrospecies, mesospecies or microspecies; considerable morphological overlap was evident even between subsets of the molecularly differentiable macrospecies. Characters supporting genuine taxonomic distinctions were often sufficiently subtle that they were masked by greater and more positively correlated variation that reflected strong contrasts in flower size, tepal colour or, less often, plant size. Individual macrospecies appear to represent morphological continua, within which taxonomic divisions are likely to prove arbitrary if based exclusively on morphological criteria and adequately sampled across their geographic range. It remains unclear how much of the mosaic of subtle character variation among the microspecies reflects genetic versus epigenetic or non-genetic influences and what proportion of any contrasts observed in gene frequencies can be attributed to the adaptive microevolution that is widely considered to dictate speciation in the genus. Moreover, supplementing weak morphological criteria with extrinsic criteria, typically by imposing constraints on geographic location and/or supposed pollinator preference, assumes rather than demonstrates the presence of even the weakest of species boundaries. Overall, it is clear that entities in Ophrys below the level of macrospecies have insufficiently structured variation, either phenotypic or genotypic, to be resolved into discrete, self-circumscribing ("natural") entities that can legitimately be equated with species as delimited within other less specialised plant genera. Our search for a non-arbitrary (meso)species concept competent to circumscribe an intermediate number of species has so far proven unsuccessful.
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Affiliation(s)
- Richard M. Bateman
- Jodrell Laboratory, Royal Botanic Gardens Kew, Richmond, Surrey TW9 3DS, UK
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Suetsugu K, Hirota SK, Hsu TC, Kurogi S, Imamura A, Suyama Y. Monotropastrum kirishimense (Ericaceae), a new mycoheterotrophic plant from Japan based on multifaceted evidence. JOURNAL OF PLANT RESEARCH 2023; 136:3-18. [PMID: 36445504 PMCID: PMC9832082 DOI: 10.1007/s10265-022-01422-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 10/26/2022] [Indexed: 05/10/2023]
Abstract
Due to their reduced morphology, non-photosynthetic plants have been one of the most challenging groups to delimit to species level. The mycoheterotrophic genus Monotropastrum, with the monotypic species M. humile, has been a particularly taxonomically challenging group, owing to its highly reduced vegetative and root morphology. Using integrative species delimitation, we have focused on Japanese Monotropastrum, with a special focus on an unknown taxon with rosy pink petals and sepals. We investigated its flowering phenology, morphology, molecular identity, and associated fungi. Detailed morphological investigation has indicated that it can be distinguished from M. humile by its rosy pink tepals and sepals that are generally more numerous, elliptic, and constantly appressed to the petals throughout its flowering period, and by its obscure root balls that are unified with the surrounding soil, with root tips that hardly protrude. Based on genome-wide single-nucleotide polymorphisms, molecular data has provided clear genetic differentiation between this unknown taxon and M. humile. Monotropastrum humile and this taxon are associated with different Russula lineages, even when they are sympatric. Based on this multifaceted evidence, we describe this unknown taxon as the new species M. kirishimense. Assortative mating resulting from phenological differences has likely contributed to the persistent sympatry between these two species, with distinct mycorrhizal specificity.
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Affiliation(s)
- Kenji Suetsugu
- Department of Biology, Graduate School of Science, Kobe University, Kobe, 657-8501, Japan.
- The Institute for Advanced Research, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501, Japan.
| | - Shun K Hirota
- Field Science Center, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-Onsen, Osaki, Miyagi, 989-6711, Japan
| | - Tian-Chuan Hsu
- Botanical Garden Division, Taiwan Forestry Research Institute, No. 53, Nanhai Rd., Taipei, 100, Taiwan
| | - Shuichi Kurogi
- Miyazaki Prefectural Museum of Nature and History, 2-4-4, Jingû, Miyazaki, 880-0053, Japan
| | - Akio Imamura
- Hokkaido University of Education, Sapporo, 002-8501, Japan
| | - Yoshihisa Suyama
- Field Science Center, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-Onsen, Osaki, Miyagi, 989-6711, Japan
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Zhang HP, Tao ZB, Trunschke J, Shrestha M, Scaccabarozzi D, Wang H, Ren ZX. Reproductive Isolation Among Three Nocturnal Moth-Pollinated Sympatric Habenaria Species (Orchidaceae). FRONTIERS IN PLANT SCIENCE 2022; 13:908852. [PMID: 35812980 PMCID: PMC9257206 DOI: 10.3389/fpls.2022.908852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
Comparison and quantification of multiple pre- and post-pollination barriers to interspecific hybridization are important to understand the factors promoting reproductive isolation. Such isolating factors have been studied recently in many flowering plant species which seek after the general roles and relative strengths of different pre- and post-pollination barriers. In this study, we quantified six isolating factors (ecogeographic isolation, phenological isolation, pollinator isolation, pollinia-pistil interactions, fruit production, and seed development) that could possibly be acting as reproductive barriers at different stages among three sympatric Habenaria species (H. limprichtii, H. davidii, and H. delavayi). These three species overlap geographically but occupy different microhabitats varying in soil water content. They were isolated through pollinator interactions both ethologically (pollinator preference) and mechanically (pollinia attachment site), but to a variable degree for different species pairs. Interspecific crosses between H. limprichtii and H. davidii result in high fruit set, and embryo development suggested weak post-pollination barriers, whereas bidirectional crosses of H. delavayi with either of the other two species fail to produce fruits. Our results revealed that pollinators were the most important isolating barrier including both ethological and mechanical mechanisms, to maintain the boundaries among these three sympatric Habenaria species. Our study also highlights the importance of a combination of pre-and post-pollination barriers for species co-existence in Orchidaceae.
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Affiliation(s)
- Hai-Ping Zhang
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhi-Bin Tao
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences (CAS), Wuhan, China
| | - Judith Trunschke
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
| | - Mani Shrestha
- Department of Disturbance Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Daniela Scaccabarozzi
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
- School of Molecular and Life Sciences, Curtin University, Bentley, WA, Australia
| | - Hong Wang
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
- Lijiang Forest Biodiversity National Observation and Research Station, Lijiang, China
| | - Zong-Xin Ren
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
- Lijiang Forest Biodiversity National Observation and Research Station, Lijiang, China
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Joffard N, Olofsson C, Friberg M, Sletvold N. Extensive pollinator sharing does not promote character displacement in two orchid congeners. Evolution 2022; 76:749-764. [PMID: 35188979 DOI: 10.1111/evo.14446] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/07/2022] [Accepted: 01/18/2022] [Indexed: 01/22/2023]
Abstract
Pollinator sharing between close relatives can be costly and can promote pollination niche partitioning and floral divergence. This should be reflected by a higher species divergence in sympatry than in allopatry. We tested this hypothesis in two orchid congeners with overlapping distributions and flowering times. We characterized floral traits and pollination niches and quantified pollen limitation in 15 pure and mixed populations, and we measured phenotypic selection on floral traits and performed controlled crosses in one mixed site. Most floral traits differed between species, yet pollinator sharing was extensive. Only the timing of scent emission diverged more in mixed sites than in pure sites, and this was not mirrored by the timing of pollinator visitation. We did not detect divergent selection on floral traits. Seed production was pollen limited in most populations but not more severely in mixed sites than in pure sites. Interspecific crosses produced the same or a higher proportion of viable seeds than intraspecific crosses. The two orchid species attract the same pollinator species despite showing divergent floral traits. However, this does not promote character displacement, implying a low cost of pollinator sharing. Our results highlight the importance of characterizing both traits and ecological niches in character displacement studies.
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Affiliation(s)
- Nina Joffard
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, 752 36, Sweden.,University of Lille, UMR 8198 - Evo-Eco-Paleo, Villeneuve d'Ascq, F-59655, France
| | - Caroliné Olofsson
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, 752 36, Sweden
| | - Magne Friberg
- Department of Biology, Lund University, Lund, SE-223 62, Sweden
| | - Nina Sletvold
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, 752 36, Sweden
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Waterton J, Cleland EE. Vertebrate herbivory weakens directional selection for earlier emergence in competition. Evol Lett 2021; 5:265-276. [PMID: 34136274 PMCID: PMC8190447 DOI: 10.1002/evl3.222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 01/08/2021] [Accepted: 02/04/2021] [Indexed: 11/10/2022] Open
Abstract
The timing of seedling emergence is strongly linked with fitness because it determines the biotic and abiotic environment experienced by plants in this vulnerable life stage. Experiments and observations consistently find that earlier-emerging plants have a competitive advantage over those emerging later. However, substantial genetic and phenotypic variation in emergence timing is harbored within and among plant populations, making it important to characterize the selective agents-including biotic interactions-that contribute to this variation. In seasonal herbaceous communities, we hypothesized that consumption of early-emerging individuals by vertebrates could weaken the strength of directional selection for earlier emergence in competitive environments. To investigate this, we carried out phenotypic selection analyses on emergence timing in two California grass species, the native Stipa pulchra and non-native Bromus diandrus, growing in intraspecific competitive neighborhoods with and without vertebrate herbivore exclusion. Vertebrate herbivores consistently weakened directional selection for earlier emergence. Our results demonstrate that vertebrate herbivores play an underappreciated selective role on phenology in plant populations, with implications for contemporary evolution, such as the potential of species to adapt to global environmental changes.
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Affiliation(s)
- Joseph Waterton
- Department of Ecology, Behavior, and Evolution Section University of California San Diego La Jolla California 92093.,Current Address: Department of Biology Indiana University Bloomington Indiana 47405
| | - Elsa E Cleland
- Department of Ecology, Behavior, and Evolution Section University of California San Diego La Jolla California 92093
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Bateman RM, Rudall PJ, Denholm I. In situ morphometric survey elucidates the evolutionary systematics of the orchid genus Gymnadenia in the British Isles. SYST BIODIVERS 2021. [DOI: 10.1080/14772000.2021.1877848] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Richard M. Bateman
- Jodrell Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, Surrey, UK
| | - Paula J. Rudall
- Jodrell Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, Surrey, UK
| | - Ian Denholm
- Department of Biological and Environmental Sciences, University of Hertfordshire, Hatfield AL10 9AB, Hertfordshire, UK
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Bateman RM. Phenotypic versus genotypic disparity in the Eurasian orchid genus Gymnadenia: exploring the limits of phylogeny reconstruction. SYST BIODIVERS 2021. [DOI: 10.1080/14772000.2021.1877845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Richard M. Bateman
- Jodrell Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, Surrey, UK
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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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