Evolutionary Significance of Whole-Genome Duplication -- Genetic Consequences of Polyploidy in Plants -- Meiosis in polyploid plants -- Origins of Novel Phenotypic Variation in Polyploids -- Identifying the Phylogenetic Context of Whole-Genome Duplications in Plants -- Ancient and Recent Polyploidy in Monocots -- Genomic Plasticity in Polyploid Wheat -- Maize (Zea mays) as a model for studying the impact of gene and regulatory sequence loss following whole genome duplication -- Polyploidy in legumes -- Jeans, genes, and genomes: cotton as a model for studying polyploidy.-Evolutionary implications of genome and karyotype restructuring in Nicotiana tabacum L -- Polyploid evolution in Spartina: Dealing with highly redundant hybrid genomes -- Allopolyploid speciation in action: the origins and evolution of Senecio cambrensis -- The early stages of polyploidy: rapid and repeated evolution in Tragopogon -- Yeast as a window into changes in genome complexity due to polyploidization -- Two Rounds of Whole Genome Duplication: Evidence and Impact on the Evolution of Vertebrate Innovations -- Polyploidy in fish and the teleost genome duplication -- Polyploidization and sex chromosome evolution in amphibians.-.

Polyploidy – whole-genome duplication (WGD) – is a fundamental driver of biodiversity with significant consequences for genome structure, organization, and evolution.  Once considered a speciation process common only in plants, polyploidy is now recognized to have played a major role in the structure, gene content, and evolution of most eukaryotic genomes.  In fact, the diversity of eukaryotes seems closely tied to multiple WGDs. Polyploidy generates new genomic interactions – initially resulting in “genomic and transcriptomic shock” – that must be resolved in a new polyploid lineage.  This process essentially acts as a “reset” button, resulting in genomic changes that may ultimately promote adaptive speciation.   This book brings together for the first time the conceptual and theoretical underpinnings of polyploid genome evolution with syntheses of the patterns and processes of genome evolution in diverse polyploid groups.  Because polyploidy is most common and best studied in plants, the book emphasizes plant models, but recent studies of vertebrates and fungi are providing fresh perspectives on factors that allow polyploid speciation and shape polyploid genomes.  The emerging paradigm is that polyploidy – through alterations in genome structure and gene regulation – generates genetic and phenotypic novelty that manifests itself at the chromosomal, physiological, and organismal levels, with long-term ecological and evolutionary consequences.