Gender and Sexual Dimorphism in Flowering Plants

ISBN-13: 9783540645979 / Angielski / Twarda / 1998 / 305 str.

Monica A. Geber; Lynda F. Delph; Todd E. Dawson

Opis

While the majority of flowering plant species are hermaphroditic, gender di- morphism, or the occurrence of two sexual morphs, has, nevertheless, evolved on repeated occasions. Gender dimorphism is found in nearly half of all angio- sperm families and in approximately 10% of flowering plant species. Where plants are dimorphic in gender, they can also be dimorphic in secondary sex characters. We refer to dimorphism of the latter kind as sexual dimorphism, in keeping with the term's usage by most zoologists. This book is about the evolution of both forms of dimorphism -hence the book's lengthy title. Gender dimorphism in plants has been an active topic of research from theoretical and empirical perspectives, and has been the focus of several re- cent reviews and book chapters. By contrast, sexual dimorphism in plants is of the much less widely appreciated. Indeed, the last comprehensive review subject dates back to Lloyd and Webb's 1977 paper on "Secondary Sex Char- we first spoke of editing a book on sexual acters in Plants. " In addition, when dimorphism in plants, some people doubted that there was enough material to justify the effort. We hope that this book not only provides an update to Lloyd and Webb's seminal work but also dispels doubts about the widespread nature of sexual dimorphism in plants. We decided to combine reviews of both gender and sexual dimorphism in a single book, because each form of dimorphism can provide the evolutionary impetus for the other.

Spis treści

1 Gender and Sexual Dimorphism in Flowering Plants: A Review of Terminology, Biogeographic patterns, Ecological Correlates, and Phylogenetic Approaches.- 1.1 Introduction.- 1.2 Terminology.- 1.3 Incidence of Dioecy.- 1.3.1 Overview.- 1.3.2 Ecological Associations.- 1.3.3 Geographic Patterns.- 1.4 Importance of Phylogenetic Approaches.- 1.5 Using Phylogenies to Understand Process and Pattern.- 1.5.1 Phylogenetic Distributions.- 1.5.2 Self-Incompatibility and Dioecy.- 1.5.3 Dioecy and Fleshy Fruits.- 1.5.4 Habitat Shifts, Pollination Biology, and Changes in Outcrossing Rates.- 1.6 Conclusions.- References.- 2 Theories of the Evolution of Dioecy.- 2.1 Introduction.- 2.2 Importance of Theoretical Models.- 2.3 Pathways to Dioecy.- 2.4 Theoretical Relationships Between Allocation of Reproductive Resources and Invasion of Populations by New Sex Morphs.- 2.4.1 Fitness in Outcrossing and Partially Selfing Cosexes and Allocation in Cosexes.- 2.4.2 Invasion of Populations by Females and Males.- 2.4.3 Effect of Cosex Allocations on Invasion by Unisexuals or Partially Sterile Types.- 2.4.4 Effects of Unisexuals on Cosex Allocations.- 2.4.5 Other Possible Routes to Dioecy.- 2.5 Testing the Theory.- 2.5.1 Comparative Tests.- 2.5.2 Gain Curves.- 2.5.3 Intraspecific Data.- 2.5.4 Genetic Data.- 2.6 Conclusions.- 2.7 References.- 3 Empirical Studies: Evolution and Maintenance of Dimorphic Breeding Systems.- 3.1 Introduction.- 3.2 Evolutionary Pathways to Gender Dimorphism.- 3.2.1 Approaches to the Study of Gender.- 3.2.1.1 Quantitative Description of Plant Gender.- 3.2.1.2 Theoretical Modelling.- 3.2.1.3 Phylogenetic Analysis.- 3.2.2 Overview of Pathways.- 3.2.3 From Cosexuality Via Gynodioecy to Dioecy.- 3.2.4 From Monoecy Via Paradioecy to Dioecy.- 3.2.5 From Cosexuality Via Androdioecy to Dioecy.- 3.2.6 From Heterostyly to Dioecy.- 3.2.7 From Duodichogamy or Heterodichogamy to Dioecy.- 3.2.8 The Evolution of Trioecy.- 3.3 Maintenance of Gender Dimorphism in Natural Populations.- 3.3.1 Sex Ratios.- 3.3.2 Evidence for an Outcrossing Advantage: Rates of Selfing and Levels of Inbreeding Depression.- 3.3.3 Relative Seed Fecundity of the Two Sexes.- 3.3.4 Relative Pollen Fecundity of the Two Sexes.- 3.3.5 Case Studies: Tests of Theoretical Models.- 3.3.5.1 Female Frequency and Habitat in Plantago lanceolata.- 3.3.5.2 Plant Vigour, Fruit Production and the Sex Ratio in Hebe strictissima.- 3.3.5.3 Rates of Selfing, Inbreeding Depression and the Sex Ratio.- 3.3.5.4 The Breakdown of Outcrossing Mechanism in Aralia.- 3.4 Directions for Future Research.- 3.4.1 Testable Predictions from Ecological Correlations.- 3.4.2 Other Research Gaps.- 3.5 Conclusions.- References.- 4 Theories of the Evolution of Sexual Dimorphism.- 4.1 Introduction.- 4.2 Models of Sexual Dimorphism.- 4.2.1 Types of Models.- 4.2.2 General Features.- 4.2.3 Sexual Dimorphism in a Dioecious Organism.- 4.2.3.1 Genetic Models.- 4.2.3.2 ESS Models.- 4.2.4 The Evolution of Gender and Sexual Dimorphism.- 4.2.4.1 ESS Models.- 4.2.4.2 Genetic Models.- 4.3 The Biology of Sexual Dimorphism.- 4.3.1 Disruptive Selection on Homologous Characters.- 4.3.1.1 Biological Circumstances.- 4.3.1.2 Theory on Disruptive Selection in Dioecious Organisms.- 4.3.1.3 Theory on the Evolution of Gender and Sexual Dimorphism.- 4.3.1.4 Disruptive Selection and Sexual Dimorphism in Plants.- 4.3.2 Ecological Competition.- 4.3.2.1 Biological Circumstances.- 4.3.2.2 Theory on Character Displacement Due to Intraspecific Competition.- 4.3.2.3 Competitive Character Displacement and SSS in Dioecious Plants.- 4.3.3 Intersexual Selection.- 4.3.3.1 Biological Circumstances.- 4.3.3.2 Theory on Intersexual Selection.- 4.3.3.3 Mate Choice and Sexual Dimorphism in Plants.- 4.4 Conclusions.- References.- 5 Sexual Dimorphism in Flowers and Inflorescences.- 5.1 Introduction.- 5.2 Patterns.- 5.2.1 Perianth Size.- 5.2.2 Perianth Shape.- 5.2.3 Nectar.- 5.2.4 Vestigial Characters.- 5.2.5 Other Flower Characters.- 5.2.6 Multi-Flower Characters.- 5.2.7 Questions.- 5.3 Evolutionary Hypotheses.- 5.3.1 Sexual Selection and Character Exaggeration.- 5.3.2 Specific Tests, Hypotheses, and Uncertainties.- 5.3.2.1 Perianth Size.- 5.3.2.2 Perianth Shape.- 5.3.2.3 Nectar.- 5.3.2.4 Vestigial Character.- 5.3.2.5 Other Flower Characters: Longevity.- 5.3.2.6 Multi-Flower Characters.- 5.4 Conclusions.- 5.4.1 Towards Quantitative Understanding.- 5.4.2 Size-Number Trade-Offs.- 5.4.3 Costs of Exaggeration.- 5.4.4 Variation in Costs and Benefits.- 5.4.5 Macro evolution.- References.- 6 Sexual Dimorphism in Live History.- 6.1 Introduction.- 6.2 Predictions Based on Sex-Differential Reproductive Investment.- 6.3 Patterns of Sexual Dimorphism in Life-History Traits.- 6.3.1 Response to Stress.- 6.3.2 Case Studies of Two Species in which the Cost of Reproduction Is Higher for Females.- 6.4 Factors Offsetting Between-Sex Differences in the Cost of Reproduction.- 6.4.1 Sexual Dimorphism in the Timing of Investment in Reproduction Versus Growth Within a Season.- 6.4.2 Sexual Dimorphism in the Timing of Flowering Within a Season.- 6.4.3 Sexual Dimorphism in the Frequency of Flowering.- 6.4.4 Sexual Dimorphism in Age of Maturation.- 6.4.5 Sexual Dimorphism in Physiological Traits.- 6.4.6 Sex-Differential Herbivory.- 6.5 The Contrary Case of Silene latifolia.- 6.6 Conclusions.- References.- 7 Dimorphism in Physiology and Morphology.- 7.1 Introduction.- 7.1.1 Causes of Sexual Dimorphism in Physiology and Vegetative Morphology.- 7.1.2 Physiological and Morphological Responses to Natural Selection.- 7.1.3 Physiological and Morphological Responses to Sexual Selection.- 7.1.4 Functional Significance of Dimorphism in Physiology and Morphology.- 7.2 History of Studies on Sexual Dimorphism in Plants.- 7.3 Sexual Dimorphism in Plant Form and Function in Species with SSS.- 7.3.1 Salix (Willow; Salicaceae).- 7.3.2 Acer negundo (Boxelder; Aceraceae).- 7.3.3 Simmondsia chinensis (Jojoba/Goat Nut; Buxaceae).- 7.3.4 Phoradendron juniperinum (Mistletoe; Viscaceae).- 7.3.5 Other Species.- 7.4 Sexual Dimorphism in Plant Form and Function in Species Without SSS.- 7.4.1 Silene latifolia (White Campion; Caryophyllaceae).- 7.4.2 Leucadendron (Proteaceae).- 7.4.3 Other Species.- 7.4.3.1 Agricultural and Weedy Species.- 7.4.3.2 Populus (Aspen; Salicaceae).- 7.5 Conclusions and Future Directions.- References.- 8 Sexual Dimorphism and Biotic Interactions.- 8.1 Introduction.- 8.1.1 Reproductive Allocation and Biotic Interactions.- 8.2 Sexual Differences in Competitive Ability.- 8.3 Sexual Differences in Herbivory.- 8.3.1 Herbivore Preference.- 8.3.2 Correlates of Sexual Differences in Herbivore Damage.- 8.3.3 Herbivore Performance on Male and Female Hosts.- 8.3.4 Sexual Differences in Response to Herbivory.- 8.4 Sexual Differences in Parasitism.- 8.4.1 Foliar Pathogens.- 8.4.2 Flower-Infecting Pathogens.- 8.4.3 Nonfungal Parasites.- 8.5 General Discussion.- 8.5.1 Biotic Interactions and Biased Sex Ratios.- 8.5.2 Evolution of Sexual Differences in Herbivory.- 8.5.3 Future Studies.- References.- 9 Genetics of Gender Dimorphism in Higher Plants.- 9.1 Introduction.- 9.2 Monoecious Plants.- 9.2.1 Gender Dimorphism in Cucumber.- 9.2.2 Molecular Biology of Gender Dimorphism in Maize.- 9.2.2.1 Tasselseed2.- 9.2.2.2 Gibberellin and gender dimorphism in maize.- 9.2.2.3 The Anther ear1 gene.- 9.3 Multigenic gender determination systems in dioecious plants.- 9.3.1 Mercurialis annua.- 9.3.2 A single gender determination locus.- 9.3.3 Sex chromosomes.- 9.3.3.1 Morphologically distinct sex chromosomes.- 9.3.3.2 Structure of sex chromosomes in plants.- 9.3.3.3 X/autosome balance can regulate gender dimorphism.- 9.3.3.4 X/autosome balance in Drosophila melanogaster.- 9.3.4 Comparison of Active Y Sex Chromosomes in Plants and Animals.- 9.3.4.1 The active-Y gender determination of white campion.- 9.3.4.2 The mammalian active-Y gender determination mechanism.- 9.3.4.3 Does dosage compensation occur in white campion?.- 9.3.5 Evolution of the active-Y chromosome: Male sterility.- 9.3.5.1 Cytoplasmic male sterility.- 9.3.5.2 Suppression of carpel or pistil development.- 9.4 Expression of MADS-box genes in unisexual flowers.- 9.5 Conclusions.- References.- 10 Quantitative Genetics of Sexual Dimorphism.- 10.1 Introduction.- 10.2 Quantitative Genetic Models of Sexual Dimorphism.- 10.3 Integration of Quantitative Genetics with Sexual Selection.- 10.4 Correlated Evolution and Divergence of Male and Female Traits in Dioecious Plants.- 10.5 Correlated Evolution and Divergence of Male and Female Function in Hermaphroditic Plants.- 10.6 Conclusions.- 10.7 References.- Taxonomic Index.

Blurb

This volume, which is written by the leading experts, consists of three sections: the first introduces readers to the tremendous variety of breeding systems and their evolution in plants and sets the stage for a consideration of the evolution of dimorphism in reproductive and non-reproductive characters. The second section deals with the evolution of secondary sexual characters, including the theory related to the evolution of sexual dimorphism and its empirical patterns. The last deals with the genetics of gender expression and of secondary sexual characters.