The Evolution of Asexual Reproduction in Plants

The main aim of this book is to understand why asexual reproduction per se and its many different forms have uneven distribution within and among different taxonomic groups. This is illustrated with reference to the major groups of land plants - the bryophytes, ferns, gymnosperms and angiosperms - although in his search for answers the author has made much use of insights gleaned from studies of asexuality in animals, and the arguments presented can be applied equally to both Kingdoms.

Part 1 Prologue: preamble; reproduction, growth and the individual; sexual and asexual reproduction. Part 2 Patterns of reproduction in bryophytes and tracheophytes: patterns of reproduction in oogamous eukaryotes; sex organs and gametophyte ontogeny in bryophytes and tracheophytes; sexual and asexual reproduction in bryophytes and tracheophytes. Part 3 The costs, benefits and constraints of asexual reproduction in plants: the costs of sexual and asexual reproduction in homospores and heterospores; the capacity for asexual reproduction in homospores and heterospores. Part 4 Cosexuality, asexuality and the male function: the male function and the fitness of asexual lineages; the male function and the maintenance of asexuality; the male function and geographic parthenogenesis; the male function and pseudogamy. Part 5 The genetic control of apomixis: concepts and conundrums; the components of apomixis and the nature of their control; a model for the genetic control of generative and aposporous apomixis; verification and fine-tuning of the model. Part 6 At the court of the red queen: genetic recombination and offspring fitness; genetic recombination and meitotic reduction; the evolutionary potential of asexual organisms. Part 7 Reflections.