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Ávila-Lovera E, Winter K, Goldsmith GR. Evidence for phylogenetic signal and correlated evolution in plant-water relation traits. THE NEW PHYTOLOGIST 2023; 237:392-407. [PMID: 36271615 DOI: 10.1111/nph.18565] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 09/25/2022] [Indexed: 06/16/2023]
Abstract
Evolutionary relationships are likely to play a significant role in shaping plant physiological and structural traits observed in contemporary taxa. We review research on phylogenetic signal and correlated evolution in plant-water relation traits, which play important roles in allowing plants to acquire, use, and conserve water. We found more evidence for a phylogenetic signal in structural traits (e.g. stomatal length and stomatal density) than in physiological traits (e.g. stomatal conductance and water potential at turgor loss). Although water potential at turgor loss is the most-studied plant-water relation trait in an evolutionary context, it is the only trait consistently found to not have a phylogenetic signal. Correlated evolution was common among traits related to water movement efficiency and hydraulic safety in both leaves and stems. We conclude that evidence for phylogenetic signal varies depending on: the methodology used for its determination, that is, model-based approaches to determine phylogenetic signal such as Blomberg's K or Pagel's λ vs statistical approaches such as ANOVAs with taxonomic classification as a factor; on the number of taxa studied (size of the phylogeny); and the setting in which plants grow (field vs common garden). More explicitly and consistently considering the role of evolutionary relationships in shaping plant ecophysiology could improve our understanding of how traits compare among species, how traits are coordinated with one another, and how traits vary with the environment.
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Affiliation(s)
- Eleinis Ávila-Lovera
- Schmid College of Science and Technology, Chapman University, Orange, CA, 92866, USA
- Smithsonian Tropical Research Institute, PO Box 0843-03092, Balboa, Ancon, Panama
| | - Klaus Winter
- Smithsonian Tropical Research Institute, PO Box 0843-03092, Balboa, Ancon, Panama
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, CA, 92866, USA
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2
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Fontes CG, Pinto‐Ledezma J, Jacobsen AL, Pratt RB, Cavender‐Bares J. Adaptive variation among oaks in wood anatomical properties is shaped by climate of origin and shows limited plasticity across environments. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Clarissa G. Fontes
- Department of Ecology, Evolution and Behavior University of Minnesota Saint Paul MN USA
| | - Jesús Pinto‐Ledezma
- Department of Ecology, Evolution and Behavior University of Minnesota Saint Paul MN USA
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3
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Lamonica D, Pagel J, Schurr FM. Predicting the dynamics of establishing tree populations: A framework for statistical inference and lessons for data collection. Methods Ecol Evol 2021. [DOI: 10.1111/2041-210x.13656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dominique Lamonica
- Institute of Landscape and Plant Ecology University of Hohenheim Stuttgart Germany
- RiverLy, HYNES (Irstea‐EDF R&D) INRAE Villeurbanne France
| | - Jörn Pagel
- Institute of Landscape and Plant Ecology University of Hohenheim Stuttgart Germany
| | - Frank M. Schurr
- Institute of Landscape and Plant Ecology University of Hohenheim Stuttgart Germany
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4
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Nolting KM, Prunier R, Midgley GF, Holsinger KE. Intraspecific trait variation influences physiological performance and fitness in the South Africa shrub genus Protea (Proteaceae). ANNALS OF BOTANY 2021; 127:519-531. [PMID: 32249291 PMCID: PMC7988518 DOI: 10.1093/aob/mcaa060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 04/03/2020] [Indexed: 05/22/2023]
Abstract
BACKGROUND AND AIMS Global plant trait datasets commonly identify trait relationships that are interpreted to reflect fundamental trade-offs associated with plant strategies, but often these trait relationships are not identified when evaluating them at smaller taxonomic and spatial scales. In this study we evaluate trait relationships measured on individual plants for five widespread Protea species in South Africa to determine whether broad-scale patterns of structural trait (e.g. leaf area) and physiological trait (e.g. photosynthetic rates) relationships can be detected within natural populations, and if these traits are themselves related to plant fitness. METHODS We evaluated the variance structure (i.e. the proportional intraspecific trait variation relative to among-species variation) for nine structural traits and six physiological traits measured in wild populations. We used a multivariate path model to evaluate the relationships between structural traits and physiological traits, and the relationship between these traits and plant size and reproductive effort. KEY RESULTS While intraspecific trait variation is relatively low for structural traits, it accounts for between 50 and 100 % of the variation in physiological traits. Furthermore, we identified few trait associations between any one structural trait and physiological trait, but multivariate regressions revealed clear associations between combinations of structural traits and physiological performance (R2 = 0.37-0.64), and almost all traits had detectable associations with plant fitness. CONCLUSIONS Intraspecific variation in structural traits leads to predictable differences in individual-level physiological performance in a multivariate framework, even though the relationship of any particular structural trait to physiological performance may be weak or undetectable. Furthermore, intraspecific variation in both structural and physiological traits leads to differences in plant size and fitness. These results demonstrate the importance of considering measurements of multivariate phenotypes on individual plants when evaluating trait relationships and how trait variation influences predictions of ecological and evolutionary outcomes.
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Affiliation(s)
- Kristen M Nolting
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Rachel Prunier
- Department of Biological and Environmental Sciences, Western Connecticut State University, Danbury, CT, USAand
| | - Guy F Midgley
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Kent E Holsinger
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
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5
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Akman M, Carlson JE, Latimer AM. Climate explains population divergence in drought-induced plasticity of functional traits and gene expression in a South African Protea. Mol Ecol 2020; 30:255-273. [PMID: 33098695 DOI: 10.1111/mec.15705] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 10/04/2020] [Accepted: 10/06/2020] [Indexed: 12/18/2022]
Abstract
Long-term environmental variation often drives local adaptation and leads to trait differentiation across populations. Additionally, when traits change in an environment-dependent way through phenotypic plasticity, the genetic variation underlying plasticity will also be under selection. These processes could create a landscape of differentiation across populations in traits and their plasticity. Here, we performed a dry-down experiment under controlled conditions to measure responses in seedlings of a shrub species from the Cape Floristic Region, the common sugarbush (Protea repens). We measured morphological and physiological traits, and sequenced whole transcriptomes of leaf tissues from eight populations that represent both the climatic and the geographical distribution of this species. We found that there is substantial variation in how populations respond to drought, but we also observed common patterns such as reduced leaf size and leaf thickness, and up-regulation of stress-related and down-regulation of growth-related gene groups. Both high environmental heterogeneity and milder source site climates were associated with higher plasticity in various traits and co-expression gene networks. Associations between traits, trait plasticity, gene networks and the source site climate suggest that temperature may play a greater role in shaping these patterns when compared to precipitation, in line with recent changes in the region due to climate change. We also found that traits respond to climatic variation in an environment-dependent manner: some associations between traits and climate were apparent only under certain growing conditions. Together, our results uncover common responses of P. repens populations to drought, and climatic drivers of population differentiation in functional traits, gene expression and their plasticity.
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Affiliation(s)
- Melis Akman
- Department of Plant Sciences, UC Davis, Davis, CA, USA.,Department of Plant and Microbial Biology, UC Berkeley, Berkeley, CA, USA
| | - Jane E Carlson
- Department of Biology, Nicholls State University, Thibodaux, LA, USA.,Gulf Coast Network Inventory and Monitoring Program, National Park Services, Washington, DC, USA
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6
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Magaña Ugarte R, Escudero A, Sánchez Mata D, Gavilán RG. Changes in Foliar Functional Traits of S. pyrenaicus subsp. carpetanus under the Ongoing Climate Change: A Retrospective Survey. PLANTS (BASEL, SWITZERLAND) 2020; 9:E395. [PMID: 32210120 PMCID: PMC7154879 DOI: 10.3390/plants9030395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 05/27/2023]
Abstract
The sensitivity of stomatal behavior and patterning (i.e., distribution, density, size) to environmental stimuli, renders them crucial for defining the physiological performance of leaves. Thus, assessing long-term modifications in stomatal traits in conserved specimens arises as a valuable eco-physiological approach to predict how the rising trend of warmer, drier summers could affect plant fitness; particularly in mountain areas already experiencing climate aggravation and lacking the related monitoring schemes like Mediterranean high-mountains. Variations in foliar and stomatal traits were studied in conserved specimens of Senecio pyrenaicus subsp. carpetanus from Sierra de Guadarrama over the past 71 years. Our findings revealed decreasing trends in leaf width, stomatal size, and increasing tendency in stomatal density, all correlated with the recent 30-year climate exacerbation in these mountains. This evidenced a positive selection favoring traits that allow safeguarding plant performance under drier, hotter weather conditions. The significant relation between stomatal traits and climatic variables upholds the role of stomatal patterning in sensing environmental cues in this species, feasibly optimizing physiological responses involved in the growth-water loss trade-off. The transition to smaller, densely packed stomata observed in recent decades could indicate local-adaptive plasticity in this species, enhancing stomatal response, as coarser environmental conditions take place in Sierra de Guadarrama.
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Affiliation(s)
- Rosina Magaña Ugarte
- Unidad de Botánica, Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain; (D.S.M.); (R.G.G.)
| | - Adrián Escudero
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, 28933 Móstoles, Madrid, Spain;
| | - Daniel Sánchez Mata
- Unidad de Botánica, Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain; (D.S.M.); (R.G.G.)
| | - Rosario G. Gavilán
- Unidad de Botánica, Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain; (D.S.M.); (R.G.G.)
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7
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Cruz MV, Mori GM, Signori-Müller C, da Silva CC, Oh DH, Dassanayake M, Zucchi MI, Oliveira RS, de Souza AP. Local adaptation of a dominant coastal tree to freshwater availability and solar radiation suggested by genomic and ecophysiological approaches. Sci Rep 2019; 9:19936. [PMID: 31882752 PMCID: PMC6934818 DOI: 10.1038/s41598-019-56469-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 12/07/2019] [Indexed: 12/21/2022] Open
Abstract
Local adaptation is often a product of environmental variations in geographical space and has implications for biodiversity conservation. We investigated the role of latitudinal heterogeneity in climate on the organization of genetic and phenotypic variation in the dominant coastal tree Avicennia schaueriana. In a common garden experiment, samples from an equatorial region, with pronounced seasonality in precipitation, accumulated less biomass, and showed lower stomatal conductance and transpiration, narrower xylem vessels, smaller leaves and higher reflectance of long wavelengths by the stem epidermis than samples from a subtropical region, with seasonality in temperature and no dry season. Transcriptomic differences identified between trees sampled under field conditions at equatorial and subtropical sites, were enriched in functional categories such as responses to temperature, solar radiation, water deficit, photosynthesis and cell wall biosynthesis. Remarkably, the diversity based on genome-wide SNPs revealed a north-south genetic structure and signatures of selection were identified for loci associated with photosynthesis, anthocyanin accumulation and the responses to osmotic and hypoxia stresses. Our results suggest the existence of divergence in key resource-use characteristics, likely driven by seasonality in water deficit and solar radiation. These findings provide a basis for conservation plans and for predicting coastal plants responses to climate change.
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Affiliation(s)
- Mariana Vargas Cruz
- Department of Plant Biology, Institute of Biology, University of Campinas (Unicamp), Campinas, SP, 13083-863, Brazil
- Center for Molecular Biology and Genetic Engineering, University of Campinas (Unicamp), Campinas, SP, 13083-875, Brazil
| | - Gustavo Maruyama Mori
- Institute of Biosciences, São Paulo State University (Unesp), São Vicente, SP, 11330-900, Brazil
| | - Caroline Signori-Müller
- Department of Plant Biology, Institute of Biology, University of Campinas (Unicamp), Campinas, SP, 13083-863, Brazil
| | - Carla Cristina da Silva
- Center for Molecular Biology and Genetic Engineering, University of Campinas (Unicamp), Campinas, SP, 13083-875, Brazil
| | - Dong-Ha Oh
- Department of Biological Sciences, Louisiana State University (LSU), Louisiana, LA, 70803, United States
| | - Maheshi Dassanayake
- Department of Biological Sciences, Louisiana State University (LSU), Louisiana, LA, 70803, United States
| | | | - Rafael Silva Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas (Unicamp), Campinas, SP, 13083-863, Brazil
| | - Anete Pereira de Souza
- Department of Plant Biology, Institute of Biology, University of Campinas (Unicamp), Campinas, SP, 13083-863, Brazil.
- Center for Molecular Biology and Genetic Engineering, University of Campinas (Unicamp), Campinas, SP, 13083-875, Brazil.
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8
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Mitchell N, Holsinger KE. Microscale trait-environment associations in two closely-related South African shrubs. AMERICAN JOURNAL OF BOTANY 2019; 106:211-222. [PMID: 30768876 DOI: 10.1002/ajb2.1234] [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: 06/21/2018] [Accepted: 11/27/2018] [Indexed: 06/09/2023]
Abstract
PREMISE OF THE STUDY Plant traits are often associated with the environments in which they occur, but these associations often differ across spatial and phylogenetic scales. Here we study the relationship between microenvironment, microgeographical location, and traits within populations using co-occurring populations of two closely related evergreen shrubs in the genus Protea. METHODS We measured a suite of functional traits on 147 plants along a single steep mountainside where both species occur, and we used data-loggers and soil analyses to characterize the environment at 10 microsites spanning the elevational gradient. We used Bayesian path analyses to detect trait-environment relationships in the field for each species. We used complementary data from greenhouse grown seedlings derived from wild collected seed to determine whether associations detected in the field are the result of genetic differentiation. KEY RESULTS Microenvironmental variables differed substantially across our study site. We found strong evidence for six trait-environment associations, although these differed between species. We were unable to detect similar associations in greenhouse-grown seedlings. CONCLUSIONS Several leaf traits were associated with temperature and soil variation in the field, but the inability to detect these in the greenhouse suggests that differences in the field are not the result of genetic differentiation.
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Affiliation(s)
- Nora Mitchell
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, 06269, USA
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Kent E Holsinger
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, 06269, USA
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9
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Born J, Michalski SG. Trait expression and signatures of adaptation in response to nitrogen addition in the common wetland plant Juncus effusus. PLoS One 2019; 14:e0209886. [PMID: 30608976 PMCID: PMC6319709 DOI: 10.1371/journal.pone.0209886] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 12/13/2018] [Indexed: 01/16/2023] Open
Abstract
Wetland ecosystems are known to mitigate high nutrient loadings and thus can improve water quality and prevent potential biodiversity loss caused by eutrophication. Plant traits affect wetland processes directly through effects on accumulation or metabolization of substances, and indirectly by affecting microbial transformation processes in the soil. Understanding the causes and consequences of intraspecific variation in plant functional traits and associated ecosystem processes can aid applied ecological approaches such as wetland restoration and construction. Here we investigated molecular variation and phenotypic variation in response to three levels of nitrogen availability for a regional set of populations of the common wetland plant Juncus effusus. We asked whether trait expression reveals signatures of adaptive differentiation by comparing genetic differentiation in quantitative traits and neutral molecular markers (QST—FST comparisons) and relating trait variation to soil conditions of the plant’s origin. Molecular analyses showed that samples clustered into three very distinct genetic lineages with strong population differentiation within and among lineages. Differentiation for quantitative traits was substantial but did not exceed neutral expectations when compared across treatments or for each treatment and lineage separately. However, variation in trait expression could be explained by local soil environmental conditions of sample origin, e.g. for aboveground carbon-to-nitrogen (C:N) ratios, suggesting adaptive differentiation to contribute to trait expression even at regional level.
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Affiliation(s)
- Jennifer Born
- Department of Community Ecology (BZF), Helmholtz Centre for Environmental Research – UFZ, Halle, Germany
- * E-mail:
| | - Stefan G. Michalski
- Department of Community Ecology (BZF), Helmholtz Centre for Environmental Research – UFZ, Halle, Germany
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10
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van den Top GG, Reynolds JD, Prins HHT, Mattsson J, Green DJ, Ydenberg RC. From salmon to salmonberry: The effects of salmon‐derived nutrients on the stomatal density of leaves of the nitriphilic shrub
Rubus spectabilis. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13202] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - John D. Reynolds
- Earth to Ocean Research Group, Department of Biological Sciences Simon Fraser University Burnaby BC Canada
| | - Herbert H. T. Prins
- Resource Ecology Group Wageningen University and Research Wageningen The Netherlands
| | - Jim Mattsson
- Centre for Cell Biology, Development and Disease, Department of Biological Sciences Simon Fraser University Burnaby BC Canada
| | - David J. Green
- Centre for Wildlife Ecology, Department of Biological Sciences Simon Fraser University Burnaby BC Canada
| | - Ronald C. Ydenberg
- Resource Ecology Group Wageningen University and Research Wageningen The Netherlands
- Centre for Wildlife Ecology, Department of Biological Sciences Simon Fraser University Burnaby BC Canada
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11
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Moore TE, Schlichting CD, Aiello-Lammens ME, Mocko K, Jones CS. Divergent trait and environment relationships among parallel radiations in Pelargonium (Geraniaceae): a role for evolutionary legacy? THE NEW PHYTOLOGIST 2018; 219:794-807. [PMID: 29749630 DOI: 10.1111/nph.15196] [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: 09/21/2017] [Accepted: 03/27/2018] [Indexed: 06/08/2023]
Abstract
Functional traits in closely related lineages are expected to vary similarly along common environmental gradients as a result of shared evolutionary and biogeographic history, or legacy effects, and as a result of biophysical tradeoffs in construction. We test these predictions in Pelargonium, a relatively recent evolutionary radiation. Bayesian phylogenetic mixed effects models assessed, at the subclade level, associations between plant height, leaf area, leaf nitrogen content and leaf mass per area (LMA), and five environmental variables capturing temperature and rainfall gradients across the Greater Cape Floristic Region of South Africa. Trait-trait integration was assessed via pairwise correlations within subclades. Of 20 trait-environment associations, 17 differed among subclades. Signs of regression coefficients diverged for height, leaf area and leaf nitrogen content, but not for LMA. Subclades also differed in trait-trait relationships and these differences were modulated by rainfall seasonality. Leave-one-out cross-validation revealed that whether trait variation was better predicted by environmental predictors or trait-trait integration depended on the clade and trait in question. Legacy signals in trait-environment and trait-trait relationships were apparently lost during the earliest diversification of Pelargonium, but then retained during subsequent subclade evolution. Overall, we demonstrate that global-scale patterns are poor predictors of patterns of trait variation at finer geographic and taxonomic scales.
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Affiliation(s)
- Timothy E Moore
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, 06269-3043, USA
| | - Carl D Schlichting
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, 06269-3043, USA
| | | | - Kerri Mocko
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, 06269-3043, USA
| | - Cynthia S Jones
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, 06269-3043, USA
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12
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Mitchell N, Carlson JE, Holsinger KE. Correlated evolution between climate and suites of traits along a fast-slow continuum in the radiation of Protea. Ecol Evol 2018; 8:1853-1866. [PMID: 29435259 PMCID: PMC5792567 DOI: 10.1002/ece3.3773] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/31/2017] [Accepted: 12/06/2017] [Indexed: 12/18/2022] Open
Abstract
Evolutionary radiations are responsible for much of Earth's diversity, yet the causes of these radiations are often elusive. Determining the relative roles of adaptation and geographic isolation in diversification is vital to understanding the causes of any radiation, and whether a radiation may be labeled as "adaptive" or not. Across many groups of plants, trait-climate relationships suggest that traits are an important indicator of how plants adapt to different climates. In particular, analyses of plant functional traits in global databases suggest that there is an "economics spectrum" along which combinations of functional traits covary along a fast-slow continuum. We examine evolutionary associations among traits and between trait and climate variables on a strongly supported phylogeny in the iconic plant genus Protea to identify correlated evolution of functional traits and the climatic-niches that species occupy. Results indicate that trait diversification in Protea has climate associations along two axes of variation: correlated evolution of plant size with temperature and leaf investment with rainfall. Evidence suggests that traits and climatic-niches evolve in similar ways, although some of these associations are inconsistent with global patterns on a broader phylogenetic scale. When combined with previous experimental work suggesting that trait-climate associations are adaptive in Protea, the results presented here suggest that trait diversification in this radiation is adaptive.
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Affiliation(s)
- Nora Mitchell
- Department of Ecology and Evolutionary BiologyUniversity of ConnecticutStorrsCTUSA
| | - Jane E. Carlson
- Inventory and Monitoring ProgramGulf Coast NetworkNational Park ServiceLafayetteLAUSA
| | - Kent E. Holsinger
- Department of Ecology and Evolutionary BiologyUniversity of ConnecticutStorrsCTUSA
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13
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Prunier R, Akman M, Kremer CT, Aitken N, Chuah A, Borevitz J, Holsinger KE. Isolation by distance and isolation by environment contribute to population differentiation in Protea repens (Proteaceae L.), a widespread South African species. AMERICAN JOURNAL OF BOTANY 2017; 104:674-684. [PMID: 28500229 DOI: 10.3732/ajb.1600232] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 04/03/2017] [Indexed: 06/07/2023]
Abstract
PREMISE OF THE STUDY The Cape Floristic Region (CFR) of South Africa is renowned for its botanical diversity, but the evolutionary origins of this diversity remain controversial. Both neutral and adaptive processes have been implicated in driving diversification, but population-level studies of plants in the CFR are rare. Here, we investigate the limits to gene flow and potential environmental drivers of selection in Protea repens L. (Proteaceae L.), a widespread CFR species. METHODS We sampled 19 populations across the range of P. repens and used genotyping by sequencing to identify 2066 polymorphic loci in 663 individuals. We used a Bayesian FST outlier analysis to identify single-nucleotide polymorphisms (SNPs) marking genomic regions that may be under selection; we used those SNPs to identify potential drivers of selection and excluded them from analyses of gene flow and genetic structure. RESULTS A pattern of isolation by distance suggested limited gene flow between nearby populations. The populations of P. repens fell naturally into two or three groupings, which corresponded to an east-west split. Differences in rainfall seasonality contributed to diversification in highly divergent loci, as do barriers to gene flow that have been identified in other species. CONCLUSIONS The strong pattern of isolation by distance is in contrast to the findings in the only other widespread species in the CFR that has been similarly studied, while the effects of rainfall seasonality are consistent with well-known patterns. Assessing the generality of these results will require investigations of other CFR species.
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Affiliation(s)
- Rachel Prunier
- Department of Biological and Environmental Sciences, Western Connecticut State University, 190 White Street, Danbury, Connecticut 06810, USA
| | - Melis Akman
- Department of Plant Sciences, University of California Davis, 387 N. Quad Avenue, Davis, California 95616, USA
| | - Colin T Kremer
- Department of Ecology and Evolutionary Biology, Yale University, P.O. Box 208106, New Haven, Connecticut 06520-8106, USA
| | - Nicola Aitken
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Aaron Chuah
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Justin Borevitz
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Kent E Holsinger
- Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, U-3043, Storrs, Connecticut 06268, USA
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14
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Skeels A, Cardillo M. Environmental niche conservatism explains the accumulation of species richness in Mediterranean-hotspot plant genera. Evolution 2017; 71:582-594. [DOI: 10.1111/evo.13179] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 01/10/2017] [Accepted: 01/10/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Alexander Skeels
- Macroevolution and Macroecology Group, Research School of Biology; Australian National University; Canberra 0200 Australia
| | - Marcel Cardillo
- Macroevolution and Macroecology Group, Research School of Biology; Australian National University; Canberra 0200 Australia
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15
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Mitchell N, Lewis PO, Lemmon EM, Lemmon AR, Holsinger KE. Anchored phylogenomics improves the resolution of evolutionary relationships in the rapid radiation of Protea L. AMERICAN JOURNAL OF BOTANY 2017; 104:102-115. [PMID: 28104589 DOI: 10.3732/ajb.1600227] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 11/30/2016] [Indexed: 05/05/2023]
Abstract
PREMISE OF THE STUDY Estimating phylogenetic relationships in relatively recent evolutionary radiations is challenging, especially if short branches associated with recent divergence result in multiple gene tree histories. We combine anchored enrichment next-generation sequencing with species tree analyses to produce a robust estimate of phylogenetic relationships in the genus Protea (Proteaceae), an iconic radiation in South Africa. METHODS We sampled multiple individuals within 59 out of 112 species of Protea and 6 outgroup species for a total of 163 individuals, and obtained sequences for 498 low-copy, orthologous nuclear loci using anchored phylogenomics. We compare several approaches for building species trees, and explore gene tree-species tree discrepancies to determine whether poor phylogenetic resolution reflects a lack of informative sites, incomplete lineage sorting, or hybridization. KEY RESULTS Phylogenetic estimates from species tree approaches are similar to one another and recover previously well-supported clades within Protea, in addition to providing well-supported phylogenetic hypotheses for previously poorly resolved intrageneric relationships. Individual gene trees are markedly different from one another and from species trees. Nonetheless, analyses indicate that differences among gene trees occur primarily concerning clades supported by short branches. CONCLUSIONS Species tree methods using hundreds of nuclear loci provided strong support for many previously unresolved relationships in the radiation of the genus Protea. In cases where support for particular relationships remains low, these appear to arise from few informative sites and lack of information rather than strongly supported disagreement among gene trees.
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Affiliation(s)
- Nora Mitchell
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut 06269 United States
| | - Paul O Lewis
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut 06269 United States
| | - Emily Moriarty Lemmon
- Department of Biological Science, Florida State University, Tallahassee, Florida 32306 United States
| | - Alan R Lemmon
- Department of Scientific Computing, Florida State University, Tallahassee, Florida 32306 United States
| | - Kent E Holsinger
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut 06269 United States
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16
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Nock CJ, Baten A, Barkla BJ, Furtado A, Henry RJ, King GJ. Genome and transcriptome sequencing characterises the gene space of Macadamia integrifolia (Proteaceae). BMC Genomics 2016; 17:937. [PMID: 27855648 PMCID: PMC5114810 DOI: 10.1186/s12864-016-3272-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 11/05/2016] [Indexed: 12/18/2022] Open
Abstract
Background The large Gondwanan plant family Proteaceae is an early-diverging eudicot lineage renowned for its morphological, taxonomic and ecological diversity. Macadamia is the most economically important Proteaceae crop and represents an ancient rainforest-restricted lineage. The family is a focus for studies of adaptive radiation due to remarkable species diversification in Mediterranean-climate biodiversity hotspots, and numerous evolutionary transitions between biomes. Despite a long history of research, comparative analyses in the Proteaceae and macadamia breeding programs are restricted by a paucity of genetic information. To address this, we sequenced the genome and transcriptome of the widely grown Macadamia integrifolia cultivar 741. Results Over 95 gigabases of DNA and RNA-seq sequence data were de novo assembled and annotated. The draft assembly has a total length of 518 Mb and spans approximately 79% of the estimated genome size. Following annotation, 35,337 protein-coding genes were predicted of which over 90% were expressed in at least one of the leaf, shoot or flower tissues examined. Gene family comparisons with five other eudicot species revealed 13,689 clusters containing macadamia genes and 1005 macadamia-specific clusters, and provides evidence for linage-specific expansion of gene families involved in pathogen recognition, plant defense and monoterpene synthesis. Cyanogenesis is an important defense strategy in the Proteaceae, and a detailed analysis of macadamia gene homologues potentially involved in cyanogenic glycoside biosynthesis revealed several highly expressed candidate genes. Conclusions The gene space of macadamia provides a foundation for comparative genomics, gene discovery and the acceleration of molecular-assisted breeding. This study presents the first available genomic resources for the large basal eudicot family Proteaceae, access to most macadamia genes and opportunities to uncover the genetic basis of traits of importance for adaptation and crop improvement. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3272-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Catherine J Nock
- Southern Cross Plant Science, Southern Cross University, Military Road, NSW, Lismore, 2480, Australia.
| | - Abdul Baten
- Southern Cross Plant Science, Southern Cross University, Military Road, NSW, Lismore, 2480, Australia
| | - Bronwyn J Barkla
- Southern Cross Plant Science, Southern Cross University, Military Road, NSW, Lismore, 2480, Australia
| | - Agnelo Furtado
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Qld, 4072, Australia
| | - Robert J Henry
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Qld, 4072, Australia
| | - Graham J King
- Southern Cross Plant Science, Southern Cross University, Military Road, NSW, Lismore, 2480, Australia
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Brousseau L, Postolache D, Lascoux M, Drouzas AD, Källman T, Leonarduzzi C, Liepelt S, Piotti A, Popescu F, Roschanski AM, Zhelev P, Fady B, Vendramin GG. Local Adaptation in European Firs Assessed through Extensive Sampling across Altitudinal Gradients in Southern Europe. PLoS One 2016; 11:e0158216. [PMID: 27392065 PMCID: PMC4938419 DOI: 10.1371/journal.pone.0158216] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 06/13/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Local adaptation is a key driver of phenotypic and genetic divergence at loci responsible for adaptive traits variations in forest tree populations. Its experimental assessment requires rigorous sampling strategies such as those involving population pairs replicated across broad spatial scales. METHODS A hierarchical Bayesian model of selection (HBM) that explicitly considers both the replication of the environmental contrast and the hierarchical genetic structure among replicated study sites is introduced. Its power was assessed through simulations and compared to classical 'within-site' approaches (FDIST, BAYESCAN) and a simplified, within-site, version of the model introduced here (SBM). RESULTS HBM demonstrates that hierarchical approaches are very powerful to detect replicated patterns of adaptive divergence with low false-discovery (FDR) and false-non-discovery (FNR) rates compared to the analysis of different sites separately through within-site approaches. The hypothesis of local adaptation to altitude was further addressed by analyzing replicated Abies alba population pairs (low and high elevations) across the species' southern distribution range, where the effects of climatic selection are expected to be the strongest. For comparison, a single population pair from the closely related species A. cephalonica was also analyzed. The hierarchical model did not detect any pattern of adaptive divergence to altitude replicated in the different study sites. Instead, idiosyncratic patterns of local adaptation among sites were detected by within-site approaches. CONCLUSION Hierarchical approaches may miss idiosyncratic patterns of adaptation among sites, and we strongly recommend the use of both hierarchical (multi-site) and classical (within-site) approaches when addressing the question of adaptation across broad spatial scales.
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Affiliation(s)
- Louise Brousseau
- INRA, UR629 URFM Ecologie des Forêts Méditerranéennes, Domaine Saint Paul, Site Agroparc CS 40509, 84914 Avignon Cedex 9, France
- Institute of Biosciences and BioResources, National Research Council (IBBR-CNR), Division of Florence, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
| | - Dragos Postolache
- Institute of Biosciences and BioResources, National Research Council (IBBR-CNR), Division of Florence, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
- Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy
- National Institute of Forest Research and Development (INCDS), Research Station Simeria, Str. Biscaria 1, 335900 Simeria, Romania
| | - Martin Lascoux
- Department of Ecology and Genetics, Evolutionary Biology Center and Science for Life Laboratory, Uppsala University, 75236 Uppsala, Sweden
| | - Andreas D. Drouzas
- School of Biology, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - Thomas Källman
- Department of Ecology and Genetics, Evolutionary Biology Center and Science for Life Laboratory, Uppsala University, 75236 Uppsala, Sweden
| | - Cristina Leonarduzzi
- Institute of Biosciences and BioResources, National Research Council (IBBR-CNR), Division of Florence, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
- Institute of Biosciences and BioResources, National Research Council (IBBR-CNR), Division of Palermo, National 3. Research Council—Corso Calatafimi, 414—I-90129, Palermo (PA), Italy
| | - Sascha Liepelt
- University of Marburg, Faculty of Biology, Conservation Biology, Karl-von-Frisch-Straße 35032 Marburg, Germany
| | - Andrea Piotti
- Institute of Biosciences and BioResources, National Research Council (IBBR-CNR), Division of Florence, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
| | - Flaviu Popescu
- National Institute of Forest Research and Development (INCDS), Research Station Simeria, Str. Biscaria 1, 335900 Simeria, Romania
| | - Anna M. Roschanski
- University of Marburg, Faculty of Biology, Conservation Biology, Karl-von-Frisch-Straße 35032 Marburg, Germany
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Genebank Collections North, Inselstrasse 9, D-23999 Malchow/Poel, Germany
| | - Peter Zhelev
- University of Forestry, 10, Kl. Ohridsky Blvd., 1797 Sofia, Bulgaria
| | - Bruno Fady
- INRA, UR629 URFM Ecologie des Forêts Méditerranéennes, Domaine Saint Paul, Site Agroparc CS 40509, 84914 Avignon Cedex 9, France
| | - Giovanni Giuseppe Vendramin
- Institute of Biosciences and BioResources, National Research Council (IBBR-CNR), Division of Florence, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
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18
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Akman M, Carlson JE, Holsinger KE, Latimer AM. Transcriptome sequencing reveals population differentiation in gene expression linked to functional traits and environmental gradients in the South African shrub Protea repens. THE NEW PHYTOLOGIST 2016; 210:295-309. [PMID: 26618926 DOI: 10.1111/nph.13761] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 10/15/2015] [Indexed: 05/11/2023]
Abstract
Understanding the environmental and genetic mechanisms underlying locally adaptive trait variation across the ranges of species is a major focus of evolutionary biology. Combining transcriptome sequencing with common garden experiments on populations spanning geographical and environmental gradients holds promise for identifying such mechanisms. The South African shrub Protea repens displays diverse phenotypes in the wild along drought and temperature gradients. We grew plants from seeds collected at 19 populations spanning this species' range, and sequenced the transcriptomes of these plants to reveal gene pathways associated with adaptive trait variation. We related expression in co-expressed gene networks to trait phenotypes measured in the common garden and to source population climate. We found that expression in gene networks correlated with source-population environment and with plant traits. In particular, the activity of gene networks enriched for growth related pathways correlated strongly with source site minimum winter temperature and with leaf size, stem diameter and height in the garden. Other gene networks with enrichments for photosynthesis related genes showed associations with precipitation. Our results strongly suggest that this species displays population-level differences in gene expression that have been shaped by source population site climate, and that are reflected in trait variation along environmental gradients.
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Affiliation(s)
- Melis Akman
- Department of Plant Sciences, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA
| | - Jane E Carlson
- Department of Biological Sciences, Nicholls State University, PO Box 2021, Thibodaux, LA, 70310, USA
| | - Kent E Holsinger
- Department of Ecology & Evolutionary Biology, University of Connecticut, U-3043, Storrs, CT, 06269-3043, USA
| | - Andrew M Latimer
- Department of Plant Sciences, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA
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19
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Carlson JE, Adams CA, Holsinger KE. Intraspecific variation in stomatal traits, leaf traits and physiology reflects adaptation along aridity gradients in a South African shrub. ANNALS OF BOTANY 2016; 117:195-207. [PMID: 26424782 PMCID: PMC4701147 DOI: 10.1093/aob/mcv146] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 08/11/2015] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND AIMS Trait-environment relationships are commonly interpreted as evidence for local adaptation in plants. However, even when selection analyses support this interpretation, the mechanisms underlying differential benefits are often unknown. This study addresses this gap in knowledge using the broadly distributed South African shrub Protea repens. Specifically, the study examines whether broad-scale patterns of trait variation are consistent with spatial differences in selection and ecophysiology in the wild. METHODS In a common garden study of plants sourced from 19 populations, associations were measured between five morphological traits and three axes describing source climates. Trait-trait and trait-environment associations were analysed in a multi-response model. Within two focal populations in the wild, selection and path analyses were used to test associations between traits, fecundity and physiological performance. KEY RESULTS Across 19 populations in a common garden, stomatal density increased with the source population's mean annual temperature and decreased with its average amount of rainfall in midsummer. Concordantly, selection analysis in two natural populations revealed positive selection on stomatal density at the hotter, drier site, while failing to detect selection at the cooler, moister site. Dry-site plants with high stomatal density also had higher stomatal conductances, cooler leaf temperatures and higher light-saturated photosynthetic rates than those with low stomatal density, but no such relationships were present among wet-site plants. Leaf area, stomatal pore index and specific leaf area in the garden also co-varied with climate, but within-population differences were not associated with fitness in either wild population. CONCLUSIONS The parallel patterns of broad-scale variation, differences in selection and differences in trait-ecophysiology relationships suggest a mechanism for adaptive differentiation in stomatal density. Densely packed stomata may improve performance by increasing transpiration and cooling, but predominately in drier, hotter climates. This study uniquely shows context-dependent benefits of stomatal density--a trait rarely linked to local adaptation in plants.
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Affiliation(s)
- Jane E Carlson
- Department of Biological Sciences, Nicholls State University, P.O. Box 2021, Thibodaux, LA 70310, USA and
| | - Christopher A Adams
- Department of Biological Sciences, Nicholls State University, P.O. Box 2021, Thibodaux, LA 70310, USA and
| | - Kent E Holsinger
- Department of Ecology and Evolutionary Biology, University of Connecticut, U-3043, Storrs, CT 06269, USA
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20
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Bouchenak-Khelladi Y, Onstein RE, Xing Y, Schwery O, Linder HP. On the complexity of triggering evolutionary radiations. THE NEW PHYTOLOGIST 2015; 207:313-326. [PMID: 25690582 DOI: 10.1111/nph.13331] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Accepted: 01/15/2015] [Indexed: 05/02/2023]
Abstract
Recent developments in phylogenetic methods have made it possible to reconstruct evolutionary radiations from extant taxa, but identifying the triggers of radiations is still problematic. Here, we propose a conceptual framework to explore the role of variables that may impact radiations. We classify the variables into extrinsic conditions vs intrinsic traits, whether they provide background conditions, trigger the radiation, or modulate the radiation. We used three clades representing angiosperm phylogenetic and structural diversity (Ericaceae, Fagales and Poales) as test groups. We located radiation events, selected variables potentially associated with diversification, and inferred the temporal sequences of evolution. We found 13 shifts in diversification regimes in the three clades. We classified the associated variables, and determined whether they originated before the relevant radiation (backgrounds), originated simultaneously with the radiations (triggers), or evolved later (modulators). By applying this conceptual framework, we establish that radiations require both extrinsic conditions and intrinsic traits, but that the sequence of these is not important. We also show that diversification drivers can be detected by being more variable within a radiation than conserved traits that only allow occupation of a new habitat. This framework facilitates exploration of the causative factors of evolutionary radiations.
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Affiliation(s)
- Yanis Bouchenak-Khelladi
- Institute of Systematic Botany, University of Zurich, 107 Zollikerstrasse, Zurich, CH-8008, Switzerland
| | - Renske E Onstein
- Institute of Systematic Botany, University of Zurich, 107 Zollikerstrasse, Zurich, CH-8008, Switzerland
| | - Yaowu Xing
- Institute of Systematic Botany, University of Zurich, 107 Zollikerstrasse, Zurich, CH-8008, Switzerland
| | - Orlando Schwery
- Institute of Systematic Botany, University of Zurich, 107 Zollikerstrasse, Zurich, CH-8008, Switzerland
| | - H Peter Linder
- Institute of Systematic Botany, University of Zurich, 107 Zollikerstrasse, Zurich, CH-8008, Switzerland
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21
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Verboom GA, Bergh NG, Haiden SA, Hoffmann V, Britton MN. Topography as a driver of diversification in the Cape Floristic Region of South Africa. THE NEW PHYTOLOGIST 2015; 207:368-376. [PMID: 25708902 DOI: 10.1111/nph.13342] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 01/22/2015] [Indexed: 06/04/2023]
Abstract
The rugged topography of the Cape Floristic Region (CFR), South Africa, is frequently invoked to explain the spectacular radiation of the Cape flora, but the mechanisms involved remain unclear. Where recent authors emphasize the importance of elevation gradients as stimuli for ecological speciation, earlier workers stressed the role of topography as an isolating mechanism, particularly in montane lineages. Using six Cape plant lineages, we tested whether elevation niches are phylogenetically conserved. We then assessed whether high-elevation species are more consistently range-restricted than low-elevation species, and whether high-elevation sisters show stronger range exclusivity (allopatry) and weaker ecological and phenotypic differentiation, suggestive of nonecological speciation. Elevation niches tend to be phylogenetically conserved. Also, high-elevation species are more consistently range-restricted than low-elevation species, potentially explaining the generally stronger range exclusivity of high-elevation sisters. While the high-elevation zone is less homogeneous ecologically, more data are required to demonstrate that high-elevation sister species show generally weaker ecological and phenotypic differentiation. Topographic complexity promotes geographical isolation at high elevations, thereby providing opportunities for nonecological, vicariant speciation. While recognizing the need for additional data, we suggest that the upland and lowland floras of the CFR may differ with regard to predominant speciation mode.
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Affiliation(s)
- G Anthony Verboom
- Bolus Herbarium and Department of Biological Sciences, University of Cape Town, Private Bag, 7701, Rondebosch, South Africa
| | - Nicola G Bergh
- Compton Herbarium, South African National Biodiversity Institute, Private Bag X7, 7735, Claremont, South Africa
| | - Sarah A Haiden
- Bolus Herbarium and Department of Biological Sciences, University of Cape Town, Private Bag, 7701, Rondebosch, South Africa
| | - Vera Hoffmann
- Bolus Herbarium and Department of Biological Sciences, University of Cape Town, Private Bag, 7701, Rondebosch, South Africa
| | - Matthew N Britton
- Bolus Herbarium and Department of Biological Sciences, University of Cape Town, Private Bag, 7701, Rondebosch, South Africa
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22
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Cook‐Patton SC, Lehmann M, Parker JD. Convergence of three mangrove species towards freeze‐tolerant phenotypes at an expanding range edge. Funct Ecol 2015. [DOI: 10.1111/1365-2435.12443] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - John D. Parker
- Smithsonian Environmental Research Center Edgewater MD 21037 USA
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23
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Toräng P, Wunder J, Obeso JR, Herzog M, Coupland G, Ågren J. Large-scale adaptive differentiation in the alpine perennial herb Arabis alpina. THE NEW PHYTOLOGIST 2015; 206:459-470. [PMID: 25422098 DOI: 10.1111/nph.13176] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 10/14/2014] [Indexed: 06/04/2023]
Abstract
Information about the incidence and magnitude of local adaptation can help to predict the response of natural populations to a changing environment, and should be of particular interest in arctic and alpine environments where the effects of climate change are expected to be severe. To quantify adaptive differentiation in the arctic-alpine perennial herb Arabis alpina, we conducted reciprocal transplant experiments for 3 yr between Spanish and Scandinavian populations. At the sites of one Spanish and one Scandinavian population, we planted seedlings representing two Spanish and four Scandinavian populations, and recorded survival, flowering propensity and fecundity. The experiment was replicated in two subsequent years. The results demonstrate strong adaptive differentiation between A. alpina populations from the two regions. At the field site in Spain, survival and fruit production of Spanish populations were higher than those of Scandinavian populations, while the opposite was true at the site in Scandinavia, and these differences were consistent across years. By comparison, fitness varied little among populations from the same region. The results suggest that the magnitude and geographical scale of local adaptation need to be considered in predictions of the effects of global change on the dynamics of arctic and alpine plant populations.
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Affiliation(s)
- Per Toräng
- Department of Plant Ecology and Evolution, EBC, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden
| | - Jörg Wunder
- Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, Carl von Linné Weg 10, 50829, Cologne, Germany
| | - José Ramón Obeso
- Research Unit of Biodivesity (UO-CSIC-PA), Universidad de Oviedo, Campus de Mieres, 33600, Mieres, Spain
| | - Michel Herzog
- LECA, Université Grenoble Alpes, F-38000, Grenoble, France
| | - George Coupland
- Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, Carl von Linné Weg 10, 50829, Cologne, Germany
| | - Jon Ågren
- Department of Plant Ecology and Evolution, EBC, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden
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Mitchell N, Moore TE, Mollmann HK, Carlson JE, Mocko K, Martinez-Cabrera H, Adams C, Silander JA, Jones CS, Schlichting CD, Holsinger KE. Functional Traits in Parallel Evolutionary Radiations and Trait-Environment Associations in the Cape Floristic Region of South Africa. Am Nat 2015; 185:525-37. [DOI: 10.1086/680051] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Britton MN, Hedderson TA, Anthony Verboom G. Topography as a driver of cryptic speciation in the high-elevation cape sedge Tetraria triangularis (Boeck.) C. B. Clarke (Cyperaceae: Schoeneae). Mol Phylogenet Evol 2014; 77:96-109. [PMID: 24704302 DOI: 10.1016/j.ympev.2014.03.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 03/08/2014] [Accepted: 03/24/2014] [Indexed: 10/25/2022]
Abstract
Since some speciation mechanisms are more likely to generate morphological disparity than others, the general failure of vascular plant taxonomists to recognize cryptic diversity may bias perceptions about speciation process in plants. While the exceptional floristic richness of the South African Cape has largely been attributed to adaptive divergence ('ecological' speciation), a combination of climatic dynamism and complex topography has likely provided ample opportunities for 'non-ecological' vicariant speciation, a mechanism which is perhaps more likely to produce cryptic species. We explore the role of topography as a driver of 'non-ecological' speciation in the high-elevation sedge Tetraria triangularis. Within this species, molecular and morphological data reveal five cryptic or semi-cryptic lineages of Miocene-Pliocene age which qualify as evolutionary species. At least three of these maintain their distinctness in sites of sympatry, identifying them as biological species. Negligible range overlap, and the identification of topography as a significant predictor of range turnover, identifies speciation as allopatric and a result of impeded gene flow across low-elevation topographic features. Weak morphological and ecological divergence implies a limited role for adaptive divergence in powering speciation, with character displacement in sympatry possibly arising as a consequence of interspecific competition. Although we cannot exclude a role for disruptive selection in species differentiation, we identify isolation of populations on topographically separated mountains as the principal motor of speciation. We suggest that the importance of topography in the genesis of Cape floristic diversity has been inadequately acknowledged.
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Affiliation(s)
- Matthew N Britton
- Department of Biological Sciences and Bolus Herbarium, University of Cape Town, Private Bag, 7700 Rondebosch, South Africa.
| | - Terry A Hedderson
- Department of Biological Sciences and Bolus Herbarium, University of Cape Town, Private Bag, 7700 Rondebosch, South Africa.
| | - G Anthony Verboom
- Department of Biological Sciences and Bolus Herbarium, University of Cape Town, Private Bag, 7700 Rondebosch, South Africa.
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Brousseau L, Bonal D, Cigna J, Scotti I. Highly local environmental variability promotes intrapopulation divergence of quantitative traits: an example from tropical rain forest trees. ANNALS OF BOTANY 2013; 112:1169-79. [PMID: 24023042 PMCID: PMC3783240 DOI: 10.1093/aob/mct176] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 06/20/2013] [Indexed: 05/24/2023]
Abstract
BACKGROUND AND AIMS In habitat mosaics, plant populations face environmental heterogeneity over short geographical distances. Such steep environmental gradients can induce ecological divergence. Lowland rainforests of the Guiana Shield are characterized by sharp, short-distance environmental variations related to topography and soil characteristics (from waterlogged bottomlands on hydromorphic soils to well-drained terra firme on ferralitic soils). Continuous plant populations distributed along such gradients are an interesting system to study intrapopulation divergence at highly local scales. This study tested (1) whether conspecific populations growing in different habitats diverge at functional traits, and (2) whether they diverge in the same way as congeneric species having different habitat preferences. METHODS Phenotypic differentiation was studied within continuous populations occupying different habitats for two congeneric, sympatric, and ecologically divergent tree species (Eperua falcata and E. grandiflora, Fabaceae). Over 3000 seeds collected from three habitats were germinated and grown in a common garden experiment, and 23 morphological, biomass, resource allocation and physiological traits were measured. KEY RESULTS In both species, seedling populations native of different habitats displayed phenotypic divergence for several traits (including seedling growth, biomass allocation, leaf chemistry, photosynthesis and carbon isotope composition). This may occur through heritable genetic variation or other maternally inherited effects. For a sub-set of traits, the intraspecific divergence associated with environmental variation coincided with interspecific divergence. CONCLUSIONS The results indicate that mother trees from different habitats transmit divergent trait values to their progeny, and suggest that local environmental variation selects for different trait optima even at a very local spatial scale. Traits for which differentiation within species follows the same pattern as differentiation between species indicate that the same ecological processes underlie intra- and interspecific variation.
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Affiliation(s)
- Louise Brousseau
- INRA, UMR ‘Ecologie des Forêts de Guyane’, Campus agronomique, BP 709, 97387 Kourou cedex, French Guiana
- INRA, UMR 1137 ‘Ecologie et Ecophysiologie Forestières’, 54280 Champenoux, France
- Université de Lorraine, UMR 1137 ‘Ecologie et Ecophysiologie Forestières’, Faculté des Sciences, Vandœuvre-lès-Nancy, France
| | - Damien Bonal
- INRA, UMR ‘Ecologie des Forêts de Guyane’, Campus agronomique, BP 709, 97387 Kourou cedex, French Guiana
- INRA, UMR 1137 ‘Ecologie et Ecophysiologie Forestières’, 54280 Champenoux, France
- Université de Lorraine, UMR 1137 ‘Ecologie et Ecophysiologie Forestières’, Faculté des Sciences, Vandœuvre-lès-Nancy, France
| | - Jeremy Cigna
- INRA, UMR ‘Ecologie des Forêts de Guyane’, Campus agronomique, BP 709, 97387 Kourou cedex, French Guiana
| | - Ivan Scotti
- INRA, UMR ‘Ecologie des Forêts de Guyane’, Campus agronomique, BP 709, 97387 Kourou cedex, French Guiana
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Carlson JE, Holsinger KE. Developmental plasticity in Protea as an evolutionary response to environmental clines in the Cape Floristic Region. PLoS One 2012; 7:e52035. [PMID: 23272203 PMCID: PMC3521735 DOI: 10.1371/journal.pone.0052035] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 11/14/2012] [Indexed: 11/19/2022] Open
Abstract
Local adaptation along steep environmental gradients likely contributes to plant diversity in the Cape Region of South Africa, yet existing analyses of trait divergence are limited to static measurements of functional traits rather than trajectories of individual development. We explore whether five taxa of evergreen shrubs (Protea section Exsertae) differ in their developmental trajectories and capacity for plasticity using two environmentally-distinct common gardens in South Africa. We measured seedlings in the summer-dry season and winter-wet season of each of two consecutive years to characterize ontogeny and plasticity within years, as same-age leaf cohorts mature, and between years, i.e., from leaf one cohort to the next. We compared patterns of development between gardens to assess whether trait trajectories are programmed versus plastic and examined whether developmental differences covaried with characteristics of a seedling’s home environment. We detected plasticity in developmental trajectories for leaf area, stomatal size, stomatal pore index, and to a limited extent specific leaf area, but not for stomatal density. We showed that the species growing in the harshest environments exhibits both the smallest increase in leaf area between years and the least change in SLA and photosynthetic rates as leaves age within years. These results show that within this clade, species have diverged in developmental trajectories and plasticity as well as in mean trait values. Some of these differences may be associated with adaptation to cold and drought stress within an environmentally-complex region.
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Affiliation(s)
- Jane E. Carlson
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Kent E. Holsinger
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, United States of America
- * E-mail:
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Carlson JE, Holsinger KE. Direct and indirect selection on floral pigmentation by pollinators and seed predators in a color polymorphic South African shrub. Oecologia 2012; 171:905-19. [PMID: 23007806 DOI: 10.1007/s00442-012-2453-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Accepted: 08/24/2012] [Indexed: 12/30/2022]
Abstract
The coexistence of different color morphs is often attributed to variable selection pressures across space, time, morph frequencies, or selection agents, but the routes by which each morph is favored are rarely identified. In this study we investigated factors that influence floral color polymorphisms on a local scale in Protea, within which approximately 40% of species are polymorphic. Previous work shows that seed predators and reproductive differences likely contribute to maintaining polymorphism in four Protea species. We explored whether selection acts directly or indirectly on floral color in two populations of Protea aurea, using path analysis of pollinator behavior, nectar production, seed predation, color, morphology, and maternal fecundity fitness components. We found that avian pollinators spent more time on white morphs, likely due to nectar differences, but that this had no apparent consequences for fecundity. Instead, the number of flowers per inflorescence underpinned many of the reproductively important differences between color morphs. White morphs had more flowers per inflorescence, which itself was positively correlated with nectar production, seed predator occurrence, and total long-term seed production. The number of seeds per plant to survive predation, in contrast, was not directly associated with color or any other floral trait. Thus, although color differences may be associated with conflicting selection pressures, the selection appears to be associated with the number of flowers per inflorescence and its unmeasured correlates, rather than with inflorescence color itself.
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Affiliation(s)
- Jane E Carlson
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA.
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PRUNIER R, HOLSINGER KE, CARLSON JE. The effect of historical legacy on adaptation: do closely related species respond to the environment in the same way? J Evol Biol 2012; 25:1636-49. [DOI: 10.1111/j.1420-9101.2012.02548.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Delph LF, Andicoechea J, Steven JC, Herlihy CR, Scarpino SV, Bell DL. Environment-dependent intralocus sexual conflict in a dioecious plant. THE NEW PHYTOLOGIST 2011; 192:542-552. [PMID: 21726233 DOI: 10.1111/j.1469-8137.2011.03811.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Intralocus sexual conflict is a form of conflict that does not involve direct interactions between males and females. It arises when selection on a shared trait with a common genetic basis differs between the sexes. Environmental factors, such as resource availability, may influence the expression and evolutionary outcome of such conflict. We quantified the genetic variance-covariance matrix, G, for both sexes of Silene latifolia for floral and leaf traits, as well as the between-sex matrix, B. We also quantified selection on the sexes via survival for 2 yr in four natural populations that varied in water availability. Environment-dependent intralocus sexual conflict exists for specific leaf area, a trait that is genetically correlated between the sexes. Males experienced significant negative selection, but only in populations with relatively limited water availability. Females experienced weakly positive or significant stabilizing selection on the same trait. Specific leaf area is genetically correlated with flower size and number, which are sexually dimorphic in this species. The extent of intralocus sexual conflict varied with the environment. Resolution of such conflict is likely to be confounded, given that specific leaf area is highly genetically integrated with other traits that are also divergent between the sexes.
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Affiliation(s)
- Lynda F Delph
- Department of Biology, Indiana University, Bloomington, IN 47405, USA.
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