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Zattara EE, Strelin MM. 5th Argentinean Meeting on Evolutionary Biology (RABE V): Report on the "Evo-Devo" Extended Symposium. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2024; 342:335-341. [PMID: 38686706 DOI: 10.1002/jez.b.23252] [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: 01/02/2024] [Revised: 03/29/2024] [Accepted: 04/02/2024] [Indexed: 05/02/2024]
Abstract
Evolutionary developmental biology (Evo-Devo) is flourishing in Latin America, particularly Argentina, where researchers are leveraging this integrative field to unlock the secrets of the region's remarkable biodiversity. A recent symposium held at the 5th Argentinean Meeting on Evolutionary Biology (RABE V) showcased a vibrant Evo-Devo community and the diversity of its research endeavors. The symposium included 3 plenary talks, 3 short talks, and 12 posters, and spanned a range of organisms and approaches. Interestingly, the symposium highlighted a prevalence of "top-down" Evo-Devo studies in the region, where researchers first analyze existing diversity and then propose potential developmental mechanisms. This approach, driven in part by financial constraints and the region's historical focus on natural history, presents a unique opportunity to bridge disciplines like comparative biology, paleontology, and botany. The symposium's success underscores the vital role of Evo-Devo in Latin America, not only for advancing our understanding of evolution but also for providing valuable tools to conserve and manage the region's irreplaceable biodiversity. As Evo-Devo continues to grow in Latin America, fostering collaboration and knowledge exchange within the region and beyond will be crucial for realizing the full potential of this transformative field.
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Affiliation(s)
- Eduardo E Zattara
- INIBIOMA, Universidad Nacional del Comahue - CONICET, Bariloche, Rio Negro, Argentina
| | - Marina M Strelin
- INIBIOMA, Universidad Nacional del Comahue - CONICET, Bariloche, Rio Negro, Argentina
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2
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Keller B, Alther B, Jiménez A, Koutroumpa K, Mora-Carrera E, Conti E. Island plants with newly discovered reproductive traits have higher capacity for uniparental reproduction, supporting Baker's law. Sci Rep 2024; 14:11392. [PMID: 38762587 PMCID: PMC11102434 DOI: 10.1038/s41598-024-62065-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 05/13/2024] [Indexed: 05/20/2024] Open
Abstract
Uniparental reproduction is advantageous when lack of mates limits outcrossing opportunities in plants. Baker's law predicts an enrichment of uniparental reproduction in habitats colonized via long-distance dispersal, such as volcanic islands. To test it, we analyzed reproductive traits at multiple hierarchical levels and compared seed-set after selfing and crossing experiments in both island and mainland populations of Limonium lobatum, a widespread species that Baker assumed to be self-incompatible because it had been described as pollen-stigma dimorphic, i.e., characterized by floral morphs differing in pollen-surface morphology and stigma-papillae shape that are typically self-incompatible. We discovered new types and combinations of pollen and stigma traits hitherto unknown in the literature on pollen-stigma dimorphism and a lack of correspondence between such combinations and pollen compatibility. Contrary to previous reports, we conclude that Limonium lobatum comprises both self-compatible and self-incompatible plants characterized by both known and previously undescribed combinations of reproductive traits. Most importantly, plants with novel combinations are overrepresented on islands, selfed seed-set is higher in islands than the mainland, and insular plants with novel pollen-stigma trait-combinations disproportionally contribute to uniparental reproduction on islands. Our results thus support Baker's law, connecting research on reproductive and island biology.
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Affiliation(s)
- Barbara Keller
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland.
| | - Barbara Alther
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - Ares Jiménez
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - Konstantina Koutroumpa
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
- Botanischer Garten und Botanisches Museum Berlin (BGBM), Freie Universität Berlin, Berlin, Germany
| | - Emiliano Mora-Carrera
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - Elena Conti
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
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3
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Strelin MM, Diggle PK, Aizen MA. Flower heterochrony and crop yield. TRENDS IN PLANT SCIENCE 2023; 28:1360-1369. [PMID: 37612211 DOI: 10.1016/j.tplants.2023.07.013] [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: 01/16/2023] [Revised: 06/17/2023] [Accepted: 07/28/2023] [Indexed: 08/25/2023]
Abstract
Crop improvement has focused on enhancing yield, nutrient content, harvestability, and stress resistance using a trait-centered reductionist approach. This has downplayed the fact that plants are developmentally integrated and respond coordinately and predictably to genetic and environmental variation, with potential consequences for food production. Crop yield, including both fruit/seed production and the possibility of generating hybrid crop varieties, is highly dependent on flower morphology and sex, which, in turn, can be profoundly affected by slight shifts in the timing and rate of flower organ development (i.e., flower heterochrony). We argue that understanding the genetic and environmental bases of flower heterochrony and their effect on flower morphology and sex in cultivated plants and in their wild relatives can facilitate crop improvement.
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Affiliation(s)
- Marina M Strelin
- Grupo de Investigación en Ecología de la Polinización, Laboratorio Ecotono, INIBIOMA (CONICET - Universidad Nacional del Comahue), San Carlos de Bariloche, Río Negro, Argentina.
| | - Pamela K Diggle
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Marcelo A Aizen
- Grupo de Investigación en Ecología de la Polinización, Laboratorio Ecotono, INIBIOMA (CONICET - Universidad Nacional del Comahue), San Carlos de Bariloche, Río Negro, Argentina
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4
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Herting J, Schönenberger J, Sauquet H. Profile of a flower: How rates of morphological evolution drive floral diversification in Ericales and angiosperms. AMERICAN JOURNAL OF BOTANY 2023; 110:e16213. [PMID: 37459475 DOI: 10.1002/ajb2.16213] [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: 11/28/2022] [Revised: 05/26/2023] [Accepted: 05/26/2023] [Indexed: 08/12/2023]
Abstract
PREMISE Recent studies of floral disparity in the asterid order Ericales have shown that flowers vary strongly among families and that disparity is unequally distributed between the three flower modules (perianth, androecium, gynoecium). However, it remains unknown whether these patterns are driven by heterogeneous rates of morphological evolution or other factors. METHODS Here, we compiled a data set of 33 floral characters scored for 414 species of Ericales sampled from 346 genera and all 22 families. We conducted ancestral state reconstructions using an equal-rates Markov model for each character. We estimated rates of morphological evolution for Ericales and for a separate angiosperm-wide data set of 19 characters and 792 species, creating "rate profiles" for Ericales, angiosperms, and major angiosperm subclades. We compared morphological rates among flower modules within each data set separately and between data sets, and we compared rates among angiosperm subclades using the angiosperm data set. RESULTS The androecium exhibits the highest evolutionary rates across most characters, whereas most perianth and gynoecium characters evolve more slowly in both Ericales and angiosperms. Both high and low rates of morphological evolution can result in high floral disparity in Ericales. Analyses of an angiosperm-wide floral data set reveal that this pattern appears to be conserved across most major angiosperm clades. CONCLUSIONS Elevated rates of morphological evolution in the androecium of Ericales may explain the higher disparity reported for this floral module. Comparing rates of morphological evolution through rate profiles proves to be a powerful tool in understanding floral evolution.
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Affiliation(s)
- Julian Herting
- National Herbarium of New South Wales, Botanic Gardens Sydney, Locked Bag 6002, Mount Annan, NSW 2567, Australia
| | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna, A-1030, Austria
| | - Hervé Sauquet
- National Herbarium of New South Wales, Botanic Gardens Sydney, Locked Bag 6002, Mount Annan, NSW 2567, Australia
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales Sydney, NSW 2052, Australia
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5
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Artuso S, Gamisch A, Staedler YM, Schönenberger J, Comes HP. Evidence for an evo-devo-derived hypothesis on three-dimensional flower shape modularity in a tropical orchid clade. Evolution 2022; 76:2587-2604. [PMID: 36128635 PMCID: PMC9828045 DOI: 10.1111/evo.14621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 08/21/2022] [Accepted: 08/26/2022] [Indexed: 01/22/2023]
Abstract
Covarying suites of phenotypic traits, or modules, are increasingly recognized to promote morphological evolution. However, information on how modularity influences flower diversity is rare and lacking for Orchidaceae. Here, we combine high-resolution X-ray computed tomography scanning with three-dimensional geometric morphometrics and phylogenetic comparative methods to test various hypotheses about three-dimensional patterns of flower evolutionary modularity in Malagasy Bulbophyllum orchids and examine rates and modes of module evolution. Based on the four evolutionary modules identified (i.e., sepals, lateral petals, labellum + column-foot, and column-part), our data support the hypothesis that both genetic-developmental and functional adaptive factors shaped evolutionary flower trait covariation in these tropical orchids. In line with "evo-devo" studies, we also find that the labellum evolved independently from the rest of the petal whorl. Finally, we show that modules evolved with different rates, and either in a neutral fashion (only column-part) or under selective constraints, as likely imposed by pollinators. Overall, this study supports current views that modular units can enhance the range and rate of morphological evolution.
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Affiliation(s)
- Silvia Artuso
- Department of Environment and BiodiversityUniversity of SalzburgSalzburg5020Austria
| | - Alexander Gamisch
- Department of Environment and BiodiversityUniversity of SalzburgSalzburg5020Austria
| | - Yannick M. Staedler
- Department of Botany and Biodiversity ResearchUniversity of ViennaVienna1030Austria
| | - Jürg Schönenberger
- Department of Botany and Biodiversity ResearchUniversity of ViennaVienna1030Austria
| | - Hans Peter Comes
- Department of Environment and BiodiversityUniversity of SalzburgSalzburg5020Austria
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6
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Marina SM, Pamela DK. Within-individual leaf allometry and the evolution of leaf morphology: A multilevel analysis of leaf allometry in temperate Viburnum (Adoxaceae) species. Evol Dev 2022; 24:145-157. [PMID: 35971627 DOI: 10.1111/ede.12414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 11/29/2022]
Abstract
A critical issue in evolutionary biology is understanding the relationship between macroevolutionary patterns of diversity and the origin of variation at the organismal level. Among-individual allometry, the relationship between the size and shape of a structure among organisms at a fixed developmental stage, is often similar to evolutionary allometry, the relationship between the size and shape of a structure among populations or species, and the genetic and developmental process that underlie allometric relationships at both levels are thought to influence evolutionary diversification. Metameric organisms present an additional level of allometry: the relationship between the size and shape of structures within individuals. We propose that within-individual allometry is also related to evolutionary diversification among metameric organisms. We explore this idea in temperate deciduous Viburnum (Adoxaceae) species that bear two types of leaves, that is, preformed and neoformed leaves, with contrasting patterns of development. Examination of within-individual, among-individual, among-population, and among-species allometry of leaf shape in both leaf types showed that the slopes of all allometric relationships were significantly different from isometry, and their sign was consistent across allometric hierarchies. Although the allometric slope of preformed leaves was constant across allometry levels, the allometric slope of neoformed leaves became increasingly steeper. We suggest that allometric variation underlying evolutionary diversification in metameric organisms may manifest among individuals and also among their repeated structures. Moreover, structures with contrasting patterns of development within metameric organisms can experience different degrees of developmental constraint, and this can in turn affect morphological diversification.
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Affiliation(s)
- Strelin M Marina
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA.,INIBIOMA, Universidad Nacional del Comahue, CONICET, Quintral, Bariloche, Grupo de Ecología de la Polinización (EcoPol), Río Negro, Argentina
| | - Diggle K Pamela
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, USA
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7
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Chen H, Xiao Z, Ding B, Diggle PK, Yuan YW. Modular regulation of floral traits by a PRE1 homolog in Mimulus verbenaceus: implications for the role of pleiotropy in floral integration. HORTICULTURE RESEARCH 2022; 9:uhac168. [PMID: 36204206 PMCID: PMC9531339 DOI: 10.1093/hr/uhac168] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 07/18/2022] [Indexed: 06/16/2023]
Abstract
Floral traits often show correlated variation within and among species. For species with fused petals, strong correlations among corolla tube, stamen, and pistil length are particularly prevalent, and these three traits are considered an intra-floral functional module. Pleiotropy has long been implicated in such modular integration of floral traits, but empirical evidence based on actual gene function is scarce. We tested the role of pleiotropy in the expression of intra-floral modularity in the monkeyflower species Mimulus verbenaceus by transgenic manipulation of a homolog of Arabidopsis PRE1. Downregulation of MvPRE1 by RNA interference resulted in simultaneous decreases in the lengths of corolla tube, petal lobe, stamen, and pistil, but little change in calyx and leaf lengths or organ width. Overexpression of MvPRE1 caused increased corolla tube and stamen lengths, with little effect on other floral traits. Our results suggest that genes like MvPRE1 can indeed regulate multiple floral traits in a functional module but meanwhile have little effect on other modules, and that pleiotropic effects of these genes may have played an important role in the evolution of floral integration and intra-floral modularity.
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Affiliation(s)
| | | | - Baoqing Ding
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Pamela K Diggle
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
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8
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Vasseur F, Westgeest AJ, Vile D, Violle C. Solving the grand challenge of phenotypic integration: allometry across scales. Genetica 2022; 150:161-169. [PMID: 35857239 PMCID: PMC9355930 DOI: 10.1007/s10709-022-00158-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 06/13/2022] [Indexed: 11/26/2022]
Abstract
Phenotypic integration is a concept related to the cascade of trait relationships from the lowest organizational levels, i.e. genes, to the highest, i.e. whole-organism traits. However, the cause-and-effect linkages between traits are notoriously difficult to determine. In particular, we still lack a mathematical framework to model the relationships involved in the integration of phenotypic traits. Here, we argue that allometric models developed in ecology offer testable mathematical equations of trait relationships across scales. We first show that allometric relationships are pervasive in biology at different organizational scales and in different taxa. We then present mechanistic models that explain the origin of allometric relationships. In addition, we emphasized that recent studies showed that natural variation does exist for allometric parameters, suggesting a role for genetic variability, selection and evolution. Consequently, we advocate that it is time to examine the genetic determinism of allometries, as well as to question in more detail the role of genome size in subsequent scaling relationships. More broadly, a possible-but so far neglected-solution to understand phenotypic integration is to examine allometric relationships at different organizational levels (cell, tissue, organ, organism) and in contrasted species.
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Affiliation(s)
- François Vasseur
- CEFE, University Montpellier, CNRS, EPHE, IRD, Montpellier, France.
| | | | - Denis Vile
- LEPSE, University Montpellier, INRAE, Institut Agro, Montpellier, France
| | - Cyrille Violle
- CEFE, University Montpellier, CNRS, EPHE, IRD, Montpellier, France
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9
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Liao IT, Rifkin JL, Cao G, Rausher MD. Modularity and selection of nectar traits in the evolution of the selfing syndrome in Ipomoea lacunosa (Convolvulaceae). THE NEW PHYTOLOGIST 2022; 233:1505-1519. [PMID: 34783034 DOI: 10.1111/nph.17863] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 11/06/2021] [Indexed: 06/13/2023]
Abstract
Although the evolution of the selfing syndrome often involves reductions in floral size, pollen and nectar, few studies of selfing syndrome divergence have examined nectar. We investigate whether nectar traits have evolved independently of other floral size traits in the selfing syndrome, whether nectar traits diverged due to drift or selection, and the extent to which quantitative trait locus (QTL) analyses predict genetic correlations. We use F5 recombinant inbred lines (RILs) generated from a cross between Ipomoea cordatotriloba and Ipomoea lacunosa. We calculate genetic correlations to identify evolutionary modules, test whether trait divergence was due to selection, identify QTLs and perform correlation analyses to evaluate how well QTL properties reflect genetic correlations. Nectar and floral size traits form separate evolutionary modules. Selection has acted to reduce nectar traits in the selfing I. lacunosa. Genetic correlations predicted from QTL properties are consistent with observed genetic correlations. Changes in floral traits associated with the selfing syndrome reflect independent evolution of at least two evolutionary modules: nectar and floral size traits. We also demonstrate directional selection on nectar traits, which is likely to be independent of selection on floral size traits. Our study also supports the expected mechanistic link between QTL properties and genetic correlations.
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Affiliation(s)
- Irene T Liao
- Department of Biology, Duke University, Durham, NC, 27708, USA
- Department of Molecular, Cell, and Developmental Biology, University of California - Los Angeles, Los Angeles, CA, 90095, USA
| | - Joanna L Rifkin
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, M5S 3B2, Canada
| | - Gongyuan Cao
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Mark D Rausher
- Department of Biology, Duke University, Durham, NC, 27708, USA
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10
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Is There More to Within-plant Variation in Seed Size than Developmental Noise? Evol Biol 2021. [DOI: 10.1007/s11692-021-09544-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AbstractWithin-plant variation in seed size may merely reflect developmental instability, or it may be adaptive in facilitating diversifying bet-hedging, that is, production of phenotypically diverse offspring when future environments are unpredictable. To test the latter hypothesis, we analyzed patterns of variation in seed size in 11 populations of the perennial vine Dalechampia scandens grown in a common greenhouse environment. We tested whether population differences in the mean and variation of seed size covaried with environmental predictability at two different timescales. We also tested whether within-plant variation in seed size was correlated with independent measures of floral developmental instability and increased under stressful conditions. Populations differed genetically in the amount of seed-size variation occurring among plants, among infructescences within plants, and among seeds within infructescences. Within-individual variation was not detectably correlated with measures of developmental instability and did not increase under stress, but it increased weakly with short-term environmental unpredictability of precipitation at the source-population site. These results support the hypothesis that greater variation in seed size is adaptive when environmental predictability is low.
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11
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Galipot P, Damerval C, Jabbour F. The seven ways eukaryotes produce repeated colour motifs on external tissues. Biol Rev Camb Philos Soc 2021; 96:1676-1693. [PMID: 33955646 DOI: 10.1111/brv.12720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 02/03/2023]
Abstract
The external tissues of numerous eukaryote species show repeated colour patterns, usually characterized by units that are present at least twice on the body. These dotted, striped or more complex phenotypes carry out crucial biological functions, such as partner recognition, aposematism or camouflage. Very diverse mechanisms explaining the formation of repeated colour patterns in eukaryotes have been identified and described, and it is timely to review this field from an evolutionary and developmental biology perspective. We propose a novel classification consisting of seven families of primary mechanisms: Turing(-like), cellular automaton, multi-induction, physical cracking, random, neuromuscular and printing. In addition, we report six pattern modifiers, acting synergistically with these primary mechanisms to enhance the spectrum of repeated colour patterns. We discuss the limitations of our classification in light of currently unexplored extant diversity. As repeated colour patterns require both the production of a repetitive structure and colouration, we also discuss the nature of the links between these two processes. A more complete understanding of the formation of repeated colour patterns in eukaryotes will require (i) a deeper exploration of biological diversity, tackling the issue of pattern elaboration during the development of non-model taxa, and (ii) exploring some of the most promising ways to discover new families of mechanisms. Good starting points include evaluating the role of mechanisms known to produce non-repeated colour patterns and that of mechanisms responsible for repeated spatial patterns lacking colouration.
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Affiliation(s)
- Pierre Galipot
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier, CP39, Paris, 75005, France.,Génétique Quantitative et Evolution-Le Moulon, Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Gif-sur-Yvette, 91190, France
| | - Catherine Damerval
- Génétique Quantitative et Evolution-Le Moulon, Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Gif-sur-Yvette, 91190, France
| | - Florian Jabbour
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier, CP39, Paris, 75005, France
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12
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March-Salas M, Fandos G, Fitze PS. Effects of intrinsic environmental predictability on intra-individual and intra-population variability of plant reproductive traits and eco-evolutionary consequences. ANNALS OF BOTANY 2021; 127:413-423. [PMID: 32421780 PMCID: PMC7988524 DOI: 10.1093/aob/mcaa096] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 05/14/2020] [Indexed: 05/22/2023]
Abstract
BACKGROUND AND AIMS It is widely accepted that changes in the environment affect mean trait expression, but little is known about how the environment shapes intra-individual and intra-population variance. Theory suggests that intra-individual variance might be plastic and under natural selection, rather than reflecting developmental noise, but evidence for this hypothesis is scarce. Here, we experimentally tested whether differences in intrinsic environmental predictability affect intra-individual and intra-population variability of different reproductive traits, and whether intra-individual variability is under selection. METHODS Under field conditions, we subjected Onobrychis viciifolia to more and less predictable precipitation over 4 generations and 4 years. We analysed effects on the coefficient of intra-individual variation (CVi-i) and the coefficient of intra-population variation (CVi-p), assessed whether the coefficients of intra-individual variation (CsVi-i) are under natural selection and tested for transgenerational responses (ancestor environmental effects on offspring). KEY RESULTS Less predictable precipitation led to higher CsVi-i and CsVi-p, consistent with plastic responses. The CsVi-i of all studied traits were under consistent stabilizing selection, and precipitation predictability affected the strength of selection and the location of the optimal CVi-i of a single trait. All CsVi-i differed from the optimal CVi-i and the maternal and offspring CsVi-i were positively correlated, showing that there was scope for change. Nevertheless, no consistent transgenerational effects were found in any of the three descendant generations, which contrasts with recent studies that detected rapid transgenerational responses in the trait means of different plant species. This suggests that changes in intra-individual variability take longer to evolve than changes in trait means, which may explain why high intra-individual variability is maintained, despite the stabilizing selection. CONCLUSIONS The results indicate that plastic changes of intra-individual variability are an important determinant of whether plants will be able to cope with changes in environmental predictability induced by the currently observed climatic change.
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Affiliation(s)
- Martí March-Salas
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal, Madrid, Spain
- Department of Biodiversity and Ecologic Restoration, Instituto Pirenaico de Ecología (IPE-CSIC), Avda. Nuestra Señora de la Victoria, Jaca, Spain
- For correspondence. E-mail or
| | - Guillermo Fandos
- Department of Geography, Humboldt-Universität zu Berlin, Rudower Chaussee, Berlin, Germany
| | - Patrick S Fitze
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal, Madrid, Spain
- Department of Biodiversity and Ecologic Restoration, Instituto Pirenaico de Ecología (IPE-CSIC), Avda. Nuestra Señora de la Victoria, Jaca, Spain
- For correspondence. E-mail or
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13
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Dellinger AS. Pollination syndromes in the 21 st century: where do we stand and where may we go? THE NEW PHYTOLOGIST 2020; 228:1193-1213. [PMID: 33460152 DOI: 10.1111/nph.16793] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/31/2020] [Indexed: 06/12/2023]
Abstract
Pollination syndromes, recurring suites of floral traits appearing in connection with specific functional pollinator groups, have served for decades to organise floral diversity under a functional-ecological perspective. Some potential caveats, such as over-simplification of complex plant-animal interactions or lack of empirical observations, have been identified and discussed in recent years. Which of these caveats do indeed cause problems, which have been solved and where do future possibilities lie? I address these questions in a review of the pollination-syndrome literature of 2010 to 2019. I show that the majority of studies was based on detailed empirical pollinator observations and could reliably predict pollinators based on a few floral traits such as colour, shape or reward. Some traits (i.e. colour) were less reliable in predicting pollinators than others (i.e. reward, corolla width), however. I stress that future studies should consider floral traits beyond those traditionally recorded to expand our understanding of mechanisms of floral evolution. I discuss statistical methods suitable for objectively analysing the interplay of system-specific evolutionary constraints, pollinator-mediated selection and adaptive trade-offs at microecological and macroecological scales. I exemplify my arguments on an empirical dataset of floral traits of a neotropical plant radiation in the family Melastomataceae.
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14
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Haaland TR, Wright J, Ratikainen II. Generalists versus specialists in fluctuating environments: a bet‐hedging perspective. OIKOS 2020. [DOI: 10.1111/oik.07109] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Thomas Ray Haaland
- Centre for Biodiversity Dynamics, Dept of Biology, Norwegian Univ. of Science and Technology Høgskoleringen 5 NO‐7044 Trondheim Norway
- Dept of Evolutionary Biology and Environmental Studies, Univ. of Zürich Winterthurerstrasse 190 CH‐8057 Zürich Switzerland
| | - Jonathan Wright
- Centre for Biodiversity Dynamics, Dept of Biology, Norwegian Univ. of Science and Technology Høgskoleringen 5 NO‐7044 Trondheim Norway
| | - Irja Ida Ratikainen
- Centre for Biodiversity Dynamics, Dept of Biology, Norwegian Univ. of Science and Technology Høgskoleringen 5 NO‐7044 Trondheim Norway
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15
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Reich D, Berger A, von Balthazar M, Chartier M, Sherafati M, Schönenberger J, Manafzadeh S, Staedler YM. Modularity and evolution of flower shape: the role of function, development, and spandrels in Erica. THE NEW PHYTOLOGIST 2020; 226:267-280. [PMID: 31765023 PMCID: PMC7065081 DOI: 10.1111/nph.16337] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 11/10/2019] [Indexed: 05/20/2023]
Abstract
Flowers have been hypothesized to contain either modules of attraction and reproduction, functional modules (pollination-effecting parts) or developmental modules (organ-specific). Do pollination specialization and syndromes influence floral modularity? In order to test these hypotheses and answer this question, we focused on the genus Erica: we gathered 3D data from flowers of 19 species with diverse syndromes via computed tomography, and for the first time tested the above-mentioned hypotheses via 3D geometric morphometrics. To provide an evolutionary framework for our results, we tested the evolutionary mode of floral shape, size and integration under the syndromes regime, and - for the first time - reconstructed the high-dimensional floral shape of their most recent common ancestor. We demonstrate that the modularity of the 3D shape of generalist flowers depends on development and that of specialists is linked to function: modules of pollen deposition and receipt in bird syndrome, and access-restriction to the floral reward in long-proboscid fly syndrome. Only size and shape principal component 1 showed multiple-optima selection, suggesting that they were co-opted during evolution to adapt flowers to novel pollinators. Whole floral shape followed an Ornstein-Uhlenbeck (selection-driven) evolutionary model, and differentiated relatively late. Flower shape modularity thus crucially depends on pollinator specialization and syndrome.
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Affiliation(s)
- Dieter Reich
- Department of Botany and Biodiversity ResearchDivision of Evolutionary and Systematic BotanyUniversity of ViennaRennweg 14Vienna1030Austria
| | - Andreas Berger
- Department of Botany and Biodiversity ResearchDivision of Evolutionary and Systematic BotanyUniversity of ViennaRennweg 14Vienna1030Austria
| | - Maria von Balthazar
- Department of Botany and Biodiversity ResearchDivision of Structural and Functional BotanyUniversity of ViennaRennweg 14Vienna1030Austria
| | - Marion Chartier
- Department of Botany and Biodiversity ResearchDivision of Structural and Functional BotanyUniversity of ViennaRennweg 14Vienna1030Austria
| | - Mahboubeh Sherafati
- Department of Plant BiologyFaculty of Biological SciencesTarbiat Modares UniversityTehran14115‐154Iran
| | - Jürg Schönenberger
- Department of Botany and Biodiversity ResearchDivision of Structural and Functional BotanyUniversity of ViennaRennweg 14Vienna1030Austria
| | - Sara Manafzadeh
- Department of Environmental Systems ScienceETH ZurichUniversitätstrasse 16Zürich8092Switzerland
| | - Yannick M. Staedler
- Department of Botany and Biodiversity ResearchDivision of Structural and Functional BotanyUniversity of ViennaRennweg 14Vienna1030Austria
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16
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Rosell JA. Bark in Woody Plants: Understanding the Diversity of a Multifunctional Structure. Integr Comp Biol 2020; 59:535-547. [PMID: 31120526 DOI: 10.1093/icb/icz057] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Most biological structures carry out multiple functions. Focusing on only one function to make adaptive inferences overlooks that manifold selection pressures and tradeoffs shape the characteristics of a multifunctional structure. Focusing on single functions can only lead to a partial picture of the causes underlying diversity and the evolutionary origin of the structure in question. I illustrate this discussion using bark as a study case. Bark comprises all the tissues surrounding the xylem in woody plants. Broadly, bark includes an inner and mostly living region and an outer, dead one. Of all plant structures, bark has the most complex anatomical structure and ontogenetic origin involving two (and often three) different meristems. Traditionally, the wide diversity in bark traits, mainly bark thickness, has been interpreted as the result of the selective pressures imposed by fire regime. However, recent research has shown that explanations based on fire regime cannot account for salient patterns of bark variation globally including the very strong inner bark thickness-stem diameter scaling, which is likely due to metabolic needs, and the very high intracommunity variation in total, inner, and outer bark thickness, and in inner:outer proportions. Moreover, explanations based on fire disregard that in addition to fire protection, bark carries out several other crucial functions for plants including translocation of photosynthates; storage of starch, soluble sugars, water, and other compounds; protection from herbivores, pathogens, and high temperatures; wound closure, as well as mechanical support, photosynthesis, and likely being involved in xylem embolism repair. All these functions are crucial for plant performance and are involved in synergistic (e.g., storage of water and insulation) and trade-off relationships (e.g., protection from fire vs photosynthetic activity). Focusing on only one of these functions, protection from fire has provided an incomplete picture of the selective forces shaping bark diversity and has severely hindered our incipient understanding of the functional ecology of this crucial region of woody stems. Applying a multifunctional perspective to the study of bark will allow us to address why we observe such high intracommunity variation in bark traits, why some bark trait combinations are ontogenetically impossible or penalized by selection, how bark is coordinated functionally with other plant parts, and as a result, to understand how bark contributes to the vast diversity of plant ecological strategies across the globe.
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Affiliation(s)
- Julieta A Rosell
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Apartado Postal 70-275, Ciudad de México 04510, Mexico
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17
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Modularity increases rate of floral evolution and adaptive success for functionally specialized pollination systems. Commun Biol 2019; 2:453. [PMID: 31872071 PMCID: PMC6895197 DOI: 10.1038/s42003-019-0697-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 11/11/2019] [Indexed: 11/09/2022] Open
Abstract
Angiosperm flowers have diversified in adaptation to pollinators, but are also shaped by developmental and genetic histories. The relative importance of these factors in structuring floral diversity remains unknown. We assess the effects of development, function and evolutionary history by testing competing hypotheses on floral modularity and shape evolution in Merianieae (Melastomataceae). Merianieae are characterized by different pollinator selection regimes and a developmental constraint: tubular anthers adapted to specialized buzz-pollination. Our analyses of tomography-based 3-dimensional flower models show that pollinators selected for functional modules across developmental units and that patterns of floral modularity changed during pollinator shifts. Further, we show that modularity was crucial for Merianieae to overcome the constraint of their tubular anthers through increased rates of evolution in other flower parts. We conclude that modularity may be key to the adaptive success of functionally specialized pollination systems by making flowers flexible (evolvable) for adaptation to changing selection regimes. Dellinger et al. report the characterization of different pollinator selection regimes on 3D flower models. They show that pollinators selected for functional floral modules, and that this modularity allowed certain species to overcome morphological constraints by increased evolutionary rates in other flower parts.
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18
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Harder LD, Strelin MM, Clocher IC, Kulbaba MW, Aizen MA. The dynamic mosaic phenotypes of flowering plants. THE NEW PHYTOLOGIST 2019; 224:1021-1034. [PMID: 31087328 DOI: 10.1111/nph.15916] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 05/08/2019] [Indexed: 06/09/2023]
Abstract
Ecological interaction and adaptation both depend on phenotypic characteristics. In contrast with the common conception of the 'adult' phenotype, plant bodies develop continuously during their lives. Furthermore, the different units (metamers) that comprise plant bodies are not identical copies, but vary extensively within individuals. These characteristics foster recognition of plant phenotypes as dynamic mosaics. We elaborate this conception based largely on a wide-ranging review of developmental, ecological and evolutionary studies of plant reproduction, and identify its utility in the analysis of plant form, function and diversification. An expanded phenotypic conception is warranted because dynamic mosaic features affect plant performance and evolve. Evidence demonstrates that dynamic mosaic phenotypes enable functional ontogeny, division of labour, resource and mating efficiency. In addition, dynamic mosaic features differ between individuals and experience phenotypic selection. Investigation of the characteristics and roles of dynamic and mosaic features of plant phenotypes benefits from considering within-individual variation as a function-valued trait that can be analysed with functional data methods. Phenotypic dynamics and within-individual variation arise despite an individual's genetic uniformity, and develop largely by heterogeneous gene expression and associated hormonal control. These characteristics can be heritable, so that dynamic mosaic phenotypes can evolve and diversify by natural selection.
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Affiliation(s)
- Lawrence D Harder
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Marina M Strelin
- Grupo de Ecología de la Polinización, INIBIOMA, CONICET-Universidad Nacional del Comahue, San Carlos de Bariloche, Río Negro, 8400, Argentina
- Universidad Nacional Autónoma de México, Instituto de Ecología, Ciudad de México, 04510, México
| | - Ilona C Clocher
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Mason W Kulbaba
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Marcelo A Aizen
- Grupo de Ecología de la Polinización, INIBIOMA, CONICET-Universidad Nacional del Comahue, San Carlos de Bariloche, Río Negro, 8400, Argentina
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Marshall AF, Bardua C, Gower DJ, Wilkinson M, Sherratt E, Goswami A. High-density three-dimensional morphometric analyses support conserved static (intraspecific) modularity in caecilian (Amphibia: Gymnophiona) crania. Biol J Linn Soc Lond 2019. [DOI: 10.1093/biolinnean/blz001] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Ashleigh F Marshall
- Department of Genetics, Evolution and Environment, University College London, London, UK
- Department of Life Sciences, The Natural History Museum, London, UK
| | - Carla Bardua
- Department of Genetics, Evolution and Environment, University College London, London, UK
- Department of Life Sciences, The Natural History Museum, London, UK
| | - David J Gower
- Department of Life Sciences, The Natural History Museum, London, UK
| | - Mark Wilkinson
- Department of Life Sciences, The Natural History Museum, London, UK
| | - Emma Sherratt
- Department of Life Sciences, The Natural History Museum, London, UK
- School of Biological Sciences, University of Adelaide, Adelaide, Australia
| | - Anjali Goswami
- Department of Genetics, Evolution and Environment, University College London, London, UK
- Department of Life Sciences, The Natural History Museum, London, UK
- Department of Earth Sciences, University College London, Gower Street, London, UK
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20
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Armbruster WS, Wege JA. Detecting canalization and intra-floral modularity in triggerplant (Stylidium) flowers: correlations are only part of the story. ANNALS OF BOTANY 2019; 123:355-372. [PMID: 30383191 PMCID: PMC6344225 DOI: 10.1093/aob/mcy184] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 09/18/2018] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS The Berg hypothesis proposes that specialized-flower traits experience stronger stabilizing selection than non-floral structures and predicts that variation in specialized-flower traits will be mostly uncorrelated with variation in non-floral traits. Similarly, adaptive-accuracy theory predicts lower variation (as a proportion of the mean) in floral traits than in non-floral ones. Both hypotheses can be extended to comparisons between floral traits, where different parts of the flower can be expected to experience different strengths of stabilizing selection, resulting in contrasting patterns of variation. The present study tests these ideas by analysing variation/covariation in those floral traits influencing the location of pollen placement on, and stigma contact with, pollinators ('pollination-mechanics traits', PMTs) in relation to variation/covariation in non-floral traits and floral traits not directly involved in the mechanics of pollination. The prediction was that PMTs are canalized (buffered against genetic and environmental variation) relative to attraction traits, as manifested in lower variances and modular independence. METHODS Floral and inflorescence structures of ten species of triggerplants (Stylidium, Stylidiaceae) in south-western Australia were measured; the data were analysed using multivariate and bivariate approaches to detect modular structure of floral and non-floral traits and assess evidence for canalization of PMTs. KEY RESULTS Only six of the ten species had PMTs with smaller correlation coefficients than attraction traits, in contrast to the Berg expectation. However, allometric and variance patterns were generally consistent with the predictions of an extended Berg hypothesis and adaptive accuracy. There was modular separation of most floral traits from non-floral traits and clear intra-floral modular structure. PMTs showed lower proportional variation and shallower allometric slopes than pollinator-attraction traits in nine and eight, respectively, of ten species. CONCLUSIONS This study demonstrates the value of allometric and variance analyses (in addition to correlation) in assessing the evolutionary significance of floral-trait stability and plasticity.
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Affiliation(s)
- W Scott Armbruster
- School of Biological Sciences, University of Portsmouth, Portsmouth, UK
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Juliet A Wege
- Western Australian Herbarium, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Bentley, Western Australia, Australia
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21
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Felice RN, Randau M, Goswami A. A fly in a tube: Macroevolutionary expectations for integrated phenotypes. Evolution 2018; 72:2580-2594. [PMID: 30246245 PMCID: PMC6585935 DOI: 10.1111/evo.13608] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 09/07/2018] [Accepted: 09/13/2018] [Indexed: 02/03/2023]
Abstract
Phenotypic integration and modularity are ubiquitous features of complex organisms, describing the magnitude and pattern of relationships among biological traits. A key prediction is that these relationships, reflecting genetic, developmental, and functional interactions, shape evolutionary processes by governing evolvability and constraint. Over the last 60 years, a rich literature of research has quantified patterns of integration and modularity across a variety of clades and systems. Only recently has it become possible to contextualize these findings in a phylogenetic framework to understand how trait integration interacts with evolutionary tempo and mode. Here, we review the state of macroevolutionary studies of integration and modularity, synthesizing empirical and theoretical work into a conceptual framework for predicting the effects of integration on evolutionary rate and disparity: a fly in a tube. While magnitude of integration is expected to influence the potential for phenotypic variation to be produced and maintained, thus defining the shape and size of a tube in morphospace, evolutionary rate, or the speed at which a fly moves around the tube, is not necessarily controlled by trait interactions. Finally, we demonstrate this reduced disparity relative to the Brownian expectation for a given rate of evolution with an empirical example: the avian cranium.
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Affiliation(s)
- Ryan N Felice
- Department of Life Sciences, The Natural History Museum, London SW7 5DB, United Kingdom.,Department of Genetics, Evolution, and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Marcela Randau
- Department of Life Sciences, The Natural History Museum, London SW7 5DB, United Kingdom.,Department of Genetics, Evolution, and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Anjali Goswami
- Department of Life Sciences, The Natural History Museum, London SW7 5DB, United Kingdom.,Department of Genetics, Evolution, and Environment, University College London, London WC1E 6BT, United Kingdom
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22
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Smyth DR. Evolution and genetic control of the floral ground plan. THE NEW PHYTOLOGIST 2018; 220:70-86. [PMID: 29959892 DOI: 10.1111/nph.15282] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 05/21/2018] [Indexed: 06/08/2023]
Abstract
Contents Summary 70 I. Introduction 70 II. What is the floral ground plan? 71 III. Diversity and evolution of the floral ground plan 72 IV. Genetic mechanisms 77 V. What's next? 82 Acknowledgements 83 References 83 SUMMARY: The floral ground plan is a map of where and when floral organ primordia arise. New results combining the defined phylogeny of flowering plants with extensive character mapping have predicted that the angiosperm ancestor had whorls rather than spirals of floral organs in large numbers, and was bisexual. More confidently, the monocot ancestor likely had three organs in each whorl, whereas the rosid and asterid ancestor (Pentapetalae) had five, with the perianth now divided into sepals and petals. Genetic mechanisms underlying the establishment of the floral ground plan are being deduced using model species, the rosid Arabidopsis, the asterid Antirrhinum, and in grasses such as rice. In this review, evolutionary and genetic conclusions are drawn together, especially considering how known genes may control individual processes in the development and evolution of ground plans. These components include organ phyllotaxis, boundary formation, organ identity, merism (the number or organs per whorl), variation in the form of primordia, organ fusion, intercalary growth, floral symmetry, determinacy and, finally, cases where the distinction between flowers and inflorescences is blurred. It seems likely that new pathways of ground plan evolution, and new signalling mechanisms, will soon be uncovered by integrating morphological and genetic approaches.
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Affiliation(s)
- David R Smyth
- School of Biological Sciences, Monash University, Clayton Campus, Melbourne, Victoria, 3800, Australia
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23
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Sauquet H, Magallón S. Key questions and challenges in angiosperm macroevolution. THE NEW PHYTOLOGIST 2018; 219:1170-1187. [PMID: 29577323 DOI: 10.1111/nph.15104] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 02/05/2018] [Indexed: 05/26/2023]
Abstract
Contents Summary 1170 I. Introduction 1170 II. Six key questions 1172 III. Three key challenges 1177 IV. Conclusions 1181 Acknowledgements 1182 References 1183 SUMMARY: The origin and rapid diversification of angiosperms (flowering plants) represent one of the most intriguing topics in evolutionary biology. Despite considerable progress made in complementary fields over the last two decades (paleobotany, phylogenetics, ecology, evo-devo, genomics), many important questions remain. For instance, what has been the impact of mass extinctions on angiosperm diversification? Are the angiosperms an adaptive radiation? Has morphological evolution in angiosperms been gradual or pulsed? We propose that the recent and ongoing revolution in macroevolutionary methods provides an unprecedented opportunity to explore long-standing questions that probably hold important clues to understand present-day biodiversity. We present six key questions that explore the origin and diversification of angiosperms. We also identify three key challenges to address these questions: (1) the development of new integrative models that include diversification, multiple intrinsic and environmental traits, biogeography and the fossil record all at once, whilst accounting for sampling bias and heterogeneity of macroevolutionary processes through time and among lineages; (2) the need for large and standardized synthetic databases of morphological variation; and (3) continuous effort on sampling the fossil record, but with a revolution in current paleobotanical practice.
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Affiliation(s)
- Hervé Sauquet
- National Herbarium of New South Wales (NSW), Royal Botanic Gardens and Domain Trust, Sydney, NSW, 2000, Australia
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS, UMR 8079, Orsay, 91405, France
| | - Susana Magallón
- Instituto de Biología, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Coyoacán, México City, 04510, México
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24
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Tomaszewski CE, Kulbaba MW, Harder LD. Mating consequences of contrasting hermaphroditic plant sexual systems. Evolution 2018; 72:2114-2128. [PMID: 30095165 DOI: 10.1111/evo.13572] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 07/15/2018] [Indexed: 11/27/2022]
Abstract
For hermaphroditic angiosperms with multiple flowers, the sex roles can be exclusively combined in bisexual flowers (monocliny), strictly separated among different flowers (monoecy), or arrayed in mixtures of bisexual flowers with female flowers (gynomonoecy) or male flowers (andromonoecy). The hypothesized benefits favoring the evolution of these contrasting hermaphroditic sexual systems are typically examined individually, usually by assessing success through only one sex role. We tested predictions of most hypotheses experimentally with an andromonoecious species, Anticlea occidentalis (Melanthiaceae), based on the performance of intact plants (andromonoecy) and those with emasculated bisexual flowers (functionally monoecious) or emasculated male flowers (functionally monoclinous with sterile peripheral flowers). Andromonoecy in this species enables efficient, size-dependent resource allocation, emphasizing female function in large plants. Emasculation revealed that anthers in male flowers promote female mating quality (outcrossing rate and mate diversity), whereas anthers in bisexual flowers promote male mating quantity (pollen dispersal distance and probability of any siring success). Thus, different hermaphroditic sexual systems likely evolve to capitalize on suites of benefits, rather than just one, and provide compromises between quantitative and qualitative reproductive components. These compromises apparently maximize an individual's combined genetic contributions through female and male functions, rather than separate contributions through each sex role.
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Affiliation(s)
| | - Mason W Kulbaba
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada.,Current Address: Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, Minnesota, 55108
| | - Lawrence D Harder
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
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25
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Losada JM, Leslie AB. Why are the seed cones of conifers so diverse at pollination? ANNALS OF BOTANY 2018; 121:1319-1331. [PMID: 29528365 PMCID: PMC6007286 DOI: 10.1093/aob/mcy029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 02/16/2018] [Indexed: 05/24/2023]
Abstract
BACKGROUND AND AIMS Form and function relationships in plant reproductive structures have long fascinated biologists. Although the intricate associations between specific pollinators and reproductive morphology have been widely explored among animal-pollinated plants, the evolutionary processes underlying the diverse morphologies of wind-pollinated plants remain less well understood. Here we study how this diversity may have arisen by focusing on two conifer species in the pine family that have divergent reproductive cone morphologies at pollination. METHODS Standard histology methods, artificial wind pollination assays and phylogenetic analyses were used in this study. KEY RESULTS A detailed study of cone ontogeny in these species reveals that variation in the rate at which their cone scales mature means that pollination occurs at different stages in their development, and thus in association with different specific morphologies. Pollination experiments nevertheless indicate that both species effectively capture pollen. CONCLUSIONS In wind-pollinated plants, morphological diversity may result from simple variation in development among lineages rather than selective pressures for any major differences in function or performance. This work also illustrates the broader importance of developmental context in understanding plant form and function relationships; because plant reproductive structures perform many different functions over their lifetime, subtle differences in development may dramatically alter the specific morphologies that they use to meet these demands.
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Affiliation(s)
- Juan M Losada
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, USA
- Arnold Arboretum of Harvard University, Boston, MA, USA
| | - Andrew B Leslie
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, USA
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Jadeja S, Tenhumberg B. Presence of fruits decreases probability of retaining flowers in a sequentially flowering plant. AOB PLANTS 2018; 10:ply033. [PMID: 29942460 PMCID: PMC6007677 DOI: 10.1093/aobpla/ply033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/21/2018] [Indexed: 06/08/2023]
Abstract
Both intrinsic and extrinsic plant processes affect the fate of flowers along an inflorescence in sequentially flowering plants. We investigated whether the intrinsic process of competition for limited resource between fruits and flowers owing to resource preemption or sink strength of basal fruits, or architectural effects due to positional differences in the probability of retaining flowers, explains a lower probability of retaining distal flowers in Yucca glauca. Further, we investigated how the extrinsic process of seed herbivory interacts with the plant's intrinsic processes of flower retention. We carried out a field experiment to compare flower retention among nine combinations of three inflorescence treatments (basal flowers only, distal flowers only, distal flowers with presence of basal fruits) and three ovule damage treatments (no, low and high) that serve as a cue for potential future seed herbivory. Also, we quantified flower retention in naturally pollinated inflorescences. Experimental results showed that the probabilities of retaining basal and distal flowers in the absence of basal fruits were similar, thus rejecting the architectural effects hypothesis. Further, in the presence of basal fruits that were in their initial stages of growth, the probability of retaining distal flowers decreased, which supports the sink strength hypothesis. We did not see an effect of ovule damage. In naturally pollinated inflorescences, the probability of retaining distal flowers decreased with increasing number of basal fruits. Results suggest that basal fruits constitute strong resource sinks reducing the probability of retaining distal flowers. Previous studies have tested this mechanism in cultivated plants. Our study shows evidence for this mechanism in a wild flower population.
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Affiliation(s)
- Shivani Jadeja
- School of Biological Sciences, University of Nebraska, Lincoln, NE, USA
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27
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Tsai T, Diggle PK, Frye HA, Jones CS. Contrasting lengths of Pelargonium floral nectar tubes result from late differences in rate and duration of growth. ANNALS OF BOTANY 2018; 121:549-560. [PMID: 29293992 PMCID: PMC5838813 DOI: 10.1093/aob/mcx171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 11/09/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND AND AIMS Much of morphological evolution in flowers has arisen from pollinator-mediated selection, often manifest as a match between the length of the pollinator's proboscis and the depth of tubular corollas or spurs. We investigate development, growth and homology of the unique nectar tube of Pelargonium, frequently described as 'a spur adnate to the pedicel'. METHODS We focused on two species. The nectar tube of P. ionidiflorum is three times longer than that of P. odoratissimum. Light and scanning electron microscopy were carried out, and daily growth measurements were used to compare nectar tube development and vascular patterns. KEY RESULTS Nectar tubes in both species are initiated centripetally to the dorsal sepal in a space created by lateral displacement of two antepetalous stamens. The cavity deepens through subsequent intercalary growth of the receptacle that proceeds at the same rate in both species until tubes reach approx. 10 mm in length. Differences in final nectar tube lengths arise via an increase in the rate and duration of growth of the receptacle that begins just before anthesis (floral opening) and continues for several days past anthesis in P. ionidiflorum but does not occur in P. odoratissimum. Epidermal cells of the dorsal surface of the nectar tube in P. ionidiflorum are approx. 1.6 times longer than those in P. odoratissimum. Histological sections show no evidence that the nectar tube is a spur that became evolutionarily fused to the pedicel. CONCLUSIONS Nectar tubes in Pelargonium are localized cavities that form in the receptacle via intercalary growth. Differences in the rate and duration of growth just prior to and following anthesis underlie differences in final tube lengths. Because differences in cell lengths do not fully account for differences in nectar tube lengths, evolutionary diversification must involve changes in both cell cycle and cell expansion.
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Affiliation(s)
- Timothy Tsai
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Pamela K Diggle
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Henry A Frye
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Cynthia S Jones
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
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28
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Strelin MM, Benitez-Vieyra S, Fornoni J, Klingenberg CP, Cocucci A. The evolution of floral ontogenetic allometry in the Andean genus Caiophora (Loasaceae, subfam. Loasoideae). Evol Dev 2017; 20:29-39. [PMID: 29243890 DOI: 10.1111/ede.12246] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The astounding variety of angiosperm flower morphologies has evolved in response to many selective forces. Flower development is highly coordinated and involves developmental associations between size and shape, ontogenetic allometry, which in turn affect the morphology of mature flowers. Although ontogenetic allometries can act as a developmental constraint and may influence adaptive evolution, allometries can evolve themselves and may change rapidly in response to selection. We explored the evolution of ontogenetic allometry in the flowers of 11 species of Loasoideae. Seven species belong to Caiophora, which radiated recently in the central Andes, and contains species that are pollinated by bees, hummingbirds, and small rodents. According to a previous study, the diversification of Caiophora involved departures from simple allometric scaling, but the changes to allometry that enabled flower diversification have not been explored yet. We characterized the ontogenetic allometry of each species with the methods of geometric morphometrics. We studied the evolution of allometries by constructing allometric spaces, in which the allometry of each species is represented by a point and the arrangement of points indicates the relations among allometric trajectories. To examine the history of changes of ontogenetic allometries, we projected the phylogeny into the allometric spaces. Inspection of allometric spaces suggests that ontogenetic variation is limited to a few dominant features. The allometries of the two main functional flower parts under study differ in their evolutionary labilities, and patterns of variation reflect pollination systems, differences in structural organization, and abiotic environmental factors.
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Affiliation(s)
- Marina Micaela Strelin
- Laboratorio Ecotono, INIBIOMA (Universidad Nacional del Comahue-CONICET), Bariloche, Rio Negro, Argentina
| | - Santiago Benitez-Vieyra
- Universidad Nacional de Córdoba, Facultad de Ciencias Exactas, Físicas y Naturales, Córdoba, Argentina.,CONICET, Instituto Multidisciplinario de Biología Vegetal (IMBIV), Córdoba, Argentina
| | - Juan Fornoni
- Universidad Nacional de Córdoba, Facultad de Ciencias Exactas, Físicas y Naturales, Córdoba, Argentina.,Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | | | - Andrea Cocucci
- Universidad Nacional de Córdoba, Facultad de Ciencias Exactas, Físicas y Naturales, Córdoba, Argentina.,CONICET, Instituto Multidisciplinario de Biología Vegetal (IMBIV), Córdoba, Argentina
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Camargo ID, Nattero J, Careaga SA, Núñez-Farfán J. Flower-level developmental plasticity to nutrient availability in Datura stramonium: implications for the mating system. ANNALS OF BOTANY 2017; 120:603-615. [PMID: 28981570 PMCID: PMC5737225 DOI: 10.1093/aob/mcx093] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 07/10/2017] [Indexed: 05/13/2023]
Abstract
BACKGROUND AND AIMS Studies of phenotypic plasticity in plants have mainly focused on (1) the effect of environmental variation on whole-plant traits related to the number of modules rather than on (2) the phenotypic consequences of environmental variation in traits of individual modules. Since environmental and developmental factors can produce changes in traits related to the mating system, this study used the second approach to investigate whether within-individual variation in herkogamy-related traits is affected by the environment during plant development in two populations of Datura stramonium , an annual herb with a hypothesized persistent mixed mating system, and to determine which morphological traits may promote self-fertilization. METHODS Full-sib families of two Mexican populations of D. stramonium , with contrasting ecological histories, were grown under low, mid and high nutrient availability to investigate the effects of genetic, environmental and within-plant flower position on flower size, corolla, stamen and pistil lengths, and herkogamy. KEY RESULTS Populations showed differences in familial variation, plasticity and familial differences in plasticity in most floral traits analysed. In one population (Ticumán), the effect of flower position on trait variation varied among families, whereas in the other (Pedregal) the effect of flower position interacted with the nutrient environment. Flower size varied with the position of flowers, but in the opposite direction between populations in low nutrients; a systematic within-plant trend of reduction in flower size, pistil length and herkogamy with flower position increased the probability of self-fertilization in the Pedregal population. CONCLUSIONS Besides genetic variation in floral traits between and within populations, environmental variation affects phenotypic floral trait values at the whole-plant level, as well as among flower positions. The interaction between flower position and nutrient environment can affect the plant's mating system, and this differs between populations. Thus, reductions in herkogamy with flower positions may be expected in environments with either low pollinator abundance or low nutrients.
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Affiliation(s)
- Iván Darío Camargo
- Laboratorio de Genética Ecológica y Evolución, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, 04510 Distrito Federal, Mexico
- Departamento de Ecología y Territorio, Facultad de Estudios Ambientales y Rurales, Pontificia Universidad Javeriana, Bogotá, 110231594, Colombia
| | - Julieta Nattero
- Instituto de Ecología, Genética y Evolución de Buenos Aires, CONICET, EGE, FCEyN, UBA, Buenos Aires, C1428EGA, Argentina
| | - Sonia A Careaga
- Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, CONABIO, Mexico City, 14010, Distrito Federal, Mexico
| | - Juan Núñez-Farfán
- Laboratorio de Genética Ecológica y Evolución, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, 04510 Distrito Federal, Mexico
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- For correspondence. E-mail
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Sauquet H, von Balthazar M, Magallón S, Doyle JA, Endress PK, Bailes EJ, Barroso de Morais E, Bull-Hereñu K, Carrive L, Chartier M, Chomicki G, Coiro M, Cornette R, El Ottra JHL, Epicoco C, Foster CSP, Jabbour F, Haevermans A, Haevermans T, Hernández R, Little SA, Löfstrand S, Luna JA, Massoni J, Nadot S, Pamperl S, Prieu C, Reyes E, dos Santos P, Schoonderwoerd KM, Sontag S, Soulebeau A, Staedler Y, Tschan GF, Wing-Sze Leung A, Schönenberger J. The ancestral flower of angiosperms and its early diversification. Nat Commun 2017; 8:16047. [PMID: 28763051 PMCID: PMC5543309 DOI: 10.1038/ncomms16047] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 05/18/2017] [Indexed: 01/05/2023] Open
Abstract
Recent advances in molecular phylogenetics and a series of important palaeobotanical discoveries have revolutionized our understanding of angiosperm diversification. Yet, the origin and early evolution of their most characteristic feature, the flower, remains poorly understood. In particular, the structure of the ancestral flower of all living angiosperms is still uncertain. Here we report model-based reconstructions for ancestral flowers at the deepest nodes in the phylogeny of angiosperms, using the largest data set of floral traits ever assembled. We reconstruct the ancestral angiosperm flower as bisexual and radially symmetric, with more than two whorls of three separate perianth organs each (undifferentiated tepals), more than two whorls of three separate stamens each, and more than five spirally arranged separate carpels. Although uncertainty remains for some of the characters, our reconstruction allows us to propose a new plausible scenario for the early diversification of flowers, leading to new testable hypotheses for future research on angiosperms.
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Affiliation(s)
- Hervé Sauquet
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, Orsay 91405, France
| | - Maria von Balthazar
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - Susana Magallón
- Instituto de Biología, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Coyoacán, México City 04510, México
| | - James A. Doyle
- Department of Evolution and Ecology, University of California, Davis, California 95616, USA
| | - Peter K. Endress
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich 8008, Switzerland
| | - Emily J. Bailes
- School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK
| | - Erica Barroso de Morais
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich 8008, Switzerland
| | - Kester Bull-Hereñu
- Departamento de Ecología, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile
| | - Laetitia Carrive
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, Orsay 91405, France
| | - Marion Chartier
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - Guillaume Chomicki
- Systematic Botany and Mycology, Department of Biology, University of Munich LMU, Munich 80638, Germany
| | - Mario Coiro
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich 8008, Switzerland
| | - Raphaël Cornette
- Institut de Systématique, Evolution, Biodiversité, Muséum National d’Histoire Naturelle, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, 57 rue Cuvier, CP39, Paris 75005, France
| | - Juliana H. L. El Ottra
- Laboratório de Sistemática Vegetal, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277. Cidade Universitária, São Paulo 05508-090, Brazil
| | - Cyril Epicoco
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, Orsay 91405, France
| | - Charles S. P. Foster
- School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Florian Jabbour
- Institut de Systématique, Evolution, Biodiversité, Muséum National d’Histoire Naturelle, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, 57 rue Cuvier, CP39, Paris 75005, France
| | - Agathe Haevermans
- Institut de Systématique, Evolution, Biodiversité, Muséum National d’Histoire Naturelle, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, 57 rue Cuvier, CP39, Paris 75005, France
| | - Thomas Haevermans
- Institut de Systématique, Evolution, Biodiversité, Muséum National d’Histoire Naturelle, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, 57 rue Cuvier, CP39, Paris 75005, France
| | - Rebeca Hernández
- Instituto de Biología, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Coyoacán, México City 04510, México
| | - Stefan A. Little
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, Orsay 91405, France
| | - Stefan Löfstrand
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - Javier A. Luna
- Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh EH3 5LR, UK
| | - Julien Massoni
- Institute of Microbiology, ETH Zurich, Zurich 8093, Switzerland
| | - Sophie Nadot
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, Orsay 91405, France
| | - Susanne Pamperl
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - Charlotte Prieu
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, Orsay 91405, France
| | - Elisabeth Reyes
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, Orsay 91405, France
| | - Patrícia dos Santos
- Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
| | - Kristel M. Schoonderwoerd
- Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - Susanne Sontag
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - Anaëlle Soulebeau
- Institut de Systématique, Evolution, Biodiversité, Muséum National d’Histoire Naturelle, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, 57 rue Cuvier, CP39, Paris 75005, France
| | - Yannick Staedler
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - Georg F. Tschan
- Department of Plant and Environmental Sciences, University of Gothenburg, Carl Skottsbergs gata 22B, Göteborg 413 19, Sweden
| | - Amy Wing-Sze Leung
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
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Heywood JS, Michalski JS, McCann BK, Russo AD, Andres KJ, Hall AR, Middleton TC. Genetic and environmental integration of the hawkmoth pollination syndrome in Ruellia humilis (Acanthaceae). ANNALS OF BOTANY 2017; 119:1143-1155. [PMID: 28334177 PMCID: PMC5604580 DOI: 10.1093/aob/mcx003] [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: 10/01/2016] [Accepted: 01/11/2017] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIMS The serial homology of floral structures has made it difficult to assess the relative contributions of selection and constraint to floral integration. The interpretation of floral integration may also be clouded by the tacit, but largely untested, assumption that genetic and environmental perturbations affect trait correlations in similar ways. In this study, estimates of both the genetic and environmental correlations between components of the hawkmoth pollination syndrome are presented for chasmogamous flowers of Ruellia humilis , including two levels of control for serial homology. METHODS A greenhouse population for quantitative genetic analysis was generated by a partial diallel cross between field-collected plants. An average of 634 chasmogamous flowers were measured for each of eight floral traits that contribute to the hawkmoth syndrome. Genetic correlations (across parents) and environmental correlations (across replicate flowers) were estimated by restricted maximum likelihood. KEY RESULTS Stigma height, anther height and floral tube length were very tightly integrated in their responses to both genetic and environmental perturbations. The inclusion of floral disc width as a control for serial homology suggests this integration is an adaptive response to correlational selection imposed by pollinators. In contrast, integration of non-homologous traits was low. Furthermore, when comparisons between the dimensions of serially homologous structures were excluded, the genetic and environmental correlation matrices showed little congruence. CONCLUSIONS The results suggest that hawkmoths have imposed strong correlational selection on floral traits involved in the deposition and removal of pollen, and that this is a consequence of stabilizing selection on the relative positions of stigmas and anthers in the face of substantial flower size variation. Low integration of other floral traits, and conflicting patterns of genetic and environmental correlations among these traits, suggest weak or no correlational selection within the range of variability expressed within a population.
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Chartier M, Löfstrand S, von Balthazar M, Gerber S, Jabbour F, Sauquet H, Schönenberger J. How (much) do flowers vary? Unbalanced disparity among flower functional modules and a mosaic pattern of morphospace occupation in the order Ericales. Proc Biol Sci 2017; 284:20170066. [PMID: 28381623 PMCID: PMC5394665 DOI: 10.1098/rspb.2017.0066] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 03/03/2017] [Indexed: 12/21/2022] Open
Abstract
The staggering diversity of angiosperms and their flowers has fascinated scientists for centuries. However, the quantitative distribution of floral morphological diversity (disparity) among lineages and the relative contribution of functional modules (perianth, androecium and gynoecium) to total floral disparity have rarely been addressed. Focusing on a major angiosperm order (Ericales), we compiled a dataset of 37 floral traits scored for 381 extant species and nine fossils. We conducted morphospace analyses to explore phylogenetic, temporal and functional patterns of disparity. We found that the floral morphospace is organized as a continuous cloud in which most clades occupy distinct regions in a mosaic pattern, that disparity increases with clade size rather than age, and that fossils fall in a narrow portion of the space. Surprisingly, our study also revealed that among functional modules, it is the androecium that contributes most to total floral disparity in Ericales. We discuss our findings in the light of clade history, selective regimes as well as developmental and functional constraints acting on the evolution of the flower and thereby demonstrate that quantitative analyses such as the ones used here are a powerful tool to gain novel insights into the evolution and diversity of flowers.
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Affiliation(s)
- Marion Chartier
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030 Vienna, Austria
| | - Stefan Löfstrand
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030 Vienna, Austria
- Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Maria von Balthazar
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030 Vienna, Austria
| | - Sylvain Gerber
- Muséum national d'Histoire naturelle, Institut de Systématique, Évolution, Biodiversité, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, 57 rue Cuvier, CP 39, 75005 Paris, France
| | - Florian Jabbour
- Muséum national d'Histoire naturelle, Institut de Systématique, Évolution, Biodiversité, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, 57 rue Cuvier, CP 39, 75005 Paris, France
| | - Hervé Sauquet
- Laboratoire Écologie, Systématique, Évolution, Université Paris-Sud, CNRS UMR 8079, 91405 Orsay, France
| | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030 Vienna, Austria
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Neustupa J. Asymmetry and integration of cellular morphology in Micrasterias compereana. BMC Evol Biol 2017; 17:1. [PMID: 28049419 PMCID: PMC5209845 DOI: 10.1186/s12862-016-0855-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Accepted: 12/17/2016] [Indexed: 01/07/2023] Open
Abstract
Background Unicellular green algae of the genus Micrasterias (Desmidiales) have complex cells with multiple lobes and indentations, and therefore, they are considered model organisms for research on plant cell morphogenesis and variation. Micrasterias cells have a typical biradial symmetric arrangement and multiple terminal lobules. They are composed of two semicells that can be further differentiated into three structural components: the polar lobe and two lateral lobes. Experimental studies suggested that these cellular parts have specific evolutionary patterns and develop independently. In this study, different geometric morphometric methods were used to address whether the semicells of Micrasterias compereana are truly not integrated with regard to the covariation of their shape data. In addition, morphological integration within the semicells was studied to ascertain whether individual lobes constitute distinct units that may be considered as separate modules. In parallel, I sought to determine whether the main components of morphological asymmetry could highlight underlying cytomorphogenetic processes that could indicate preferred directions of variation, canalizing evolutionary changes in cellular morphology. Results Differentiation between opposite semicells constituted the most prominent subset of cellular asymmetry. The second important asymmetric pattern, recovered by the Procrustes ANOVA models, described differentiation between the adjacent lobules within the quadrants. Other asymmetric components proved to be relatively unimportant. Opposite semicells were shown to be completely independent of each other on the basis of the partial least squares analysis analyses. In addition, polar lobes were weakly integrated with adjacent lateral lobes. Conversely, higher covariance levels between the two lateral lobes of the same semicell indicated mutual interconnection and significant integration between these parts. Conclusions Micrasterias cells are composed of several successively disintegrated parts. These integration patterns concurred with presumed scenarios of morphological evolution within the lineage. In addition, asymmetric differentiation in the shape of the lobules involves two major patterns: asymmetry across the isthmus axis and among the adjacent lobules. Notably, asymmetry among the adjacent lobules may be related to evolutionary differentiation among species, but it may also point out developmental instability related to environmental factors. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0855-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jiří Neustupa
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic.
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34
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Stanton DE, Reeb C. Morphogeometric Approaches to Non-vascular Plants. FRONTIERS IN PLANT SCIENCE 2016; 7:916. [PMID: 27446146 PMCID: PMC4921491 DOI: 10.3389/fpls.2016.00916] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 06/09/2016] [Indexed: 06/02/2023]
Abstract
Morphometric analysis of organisms has undergone a dramatic renaissance in recent years, embracing a range of novel computational and imaging techniques to provide new approaches to phenotypic characterization. These innovations have often developed piece-meal, and may reflect the taxonomic specializations and biases of their creators. In this review, we aim to provide a brief introduction to applications and applicability of modern morphometrics to non-vascular land plants, an often overlooked but evolutionarily and ecologically important group. The scale and physiology of bryophytes (mosses, liverworts, and hornworts) differ in important and informative ways from more "traditional" model plants, and their inclusion has the potential to powerfully broaden perspectives in plant morphology. In particular we highlight three areas where the "bryophytic perspective" shows considerable inter-disciplinary potential: (i) bryophytes as models for intra-specific and inter-specific phenotypic variation, (ii) bryophyte growth-forms as areas for innovation in architectural modularity, and (iii) bryophytes as models of ecophysiological integration between organs, individuals, and stands. We suggest that advances should come from two-way dialog: the translation and adoption of techniques recently developed for vascular plants (and other organisms) to bryophytes and the use of bryophytes as model systems for the innovation of new techniques and paradigms in morphogeometric approaches.
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Affiliation(s)
- Daniel E. Stanton
- Department of Ecology, Evolution and Behavior, University of Minnesota – Twin Cities, Saint PaulMN, USA
| | - Catherine Reeb
- Institut de Systématique Évolution Biodiversité UMR 7205, UPMC, MNHN, CNRS, EPHE, Muséum National d’Histoire NaturelleParis, France
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35
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Esteve-Altava B. In search of morphological modules: a systematic review. Biol Rev Camb Philos Soc 2016; 92:1332-1347. [DOI: 10.1111/brv.12284] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Revised: 05/06/2016] [Accepted: 05/10/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Borja Esteve-Altava
- Department of Comparative Biomedical Sciences; Royal Veterinary College; Hawkshead Lane, North Mymms Hatfield Hertfordshire AL9 7TA UK
- Department of Anatomy; College of Medicine, Howard University; 520 W Street, NW, Numa Adams Building Washington DC 20059 USA
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36
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Functional modularity in a forcible flower mechanism: relationships among morphology, biomechanical features and fitness. Evol Ecol 2015. [DOI: 10.1007/s10682-015-9783-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Fenster CB, Reynolds RJ, Williams CW, Makowsky R, Dudash MR. Quantifying hummingbird preference for floral trait combinations: The role of selection on trait interactions in the evolution of pollination syndromes. Evolution 2015; 69:1113-27. [DOI: 10.1111/evo.12639] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 02/18/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Charles B. Fenster
- Department of Biology; University of Maryland, College Park; College Park Maryland 20742
- Mountain Lake Biological Station; 240 Salt Pond Road Pembroke Virginia 24136
| | - Richard J. Reynolds
- Department of Biology; University of Maryland, College Park; College Park Maryland 20742
- Mountain Lake Biological Station; 240 Salt Pond Road Pembroke Virginia 24136
- Division of Clinical Immunology and Rheumatology, Department of Medicine; University of Alabama at Birmingham
| | - Christopher W. Williams
- Mountain Lake Biological Station; 240 Salt Pond Road Pembroke Virginia 24136
- Frostburg State University; Frostburg Maryland 21502
- National Institutes of Health, NIDDK; Bethesda Maryland 20892
| | | | - Michele R. Dudash
- Department of Biology; University of Maryland, College Park; College Park Maryland 20742
- Mountain Lake Biological Station; 240 Salt Pond Road Pembroke Virginia 24136
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González AV, Murúa MM, Pérez F. Floral integration and pollinator diversity in the generalized plant-pollinator system of Alstroemeria ligtu (Alstroemeriaceae). Evol Ecol 2014. [DOI: 10.1007/s10682-014-9746-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Armbruster WS, Pélabon C, Bolstad GH, Hansen TF. Integrated phenotypes: understanding trait covariation in plants and animals. Philos Trans R Soc Lond B Biol Sci 2014; 369:20130245. [PMID: 25002693 PMCID: PMC4084533 DOI: 10.1098/rstb.2013.0245] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Integration and modularity refer to the patterns and processes of trait interaction and independence. Both terms have complex histories with respect to both conceptualization and quantification, resulting in a plethora of integration indices in use. We review briefly the divergent definitions, uses and measures of integration and modularity and make conceptual links to allometry. We also discuss how integration and modularity might evolve. Although integration is generally thought to be generated and maintained by correlational selection, theoretical considerations suggest the relationship is not straightforward. We caution here against uncontrolled comparisons of indices across studies. In the absence of controls for trait number, dimensionality, homology, development and function, it is difficult, or even impossible, to compare integration indices across organisms or traits. We suggest that care be invested in relating measurement to underlying theory or hypotheses, and that summative, theory-free descriptors of integration generally be avoided. The papers that follow in this Theme Issue illustrate the diversity of approaches to studying integration and modularity, highlighting strengths and pitfalls that await researchers investigating integration in plants and animals.
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Affiliation(s)
- W Scott Armbruster
- School of Biological Sciences, University of Portsmouth, Portsmouth PO12DY, UK Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775, USA Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Christophe Pélabon
- Center for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Geir H Bolstad
- Center for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Thomas F Hansen
- Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, PO Box 1066, 0316 Oslo, Norway
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