Natural neopolyploids: a stimulus for novel research.

Recently formed allopolyploid species offer unprecedented insights into the early stages of polyploid evolution. This review examines seven well-studied neopolyploids (we use 'neopolyploid' to refer to very recently formed polyploids, i.e. during the past 300 years), spanning different angiosperm families, exploring commonalities and differences in their evolutionary trajectories. Each neopolyploid provides a unique case study, demonstrating both shared patterns, such as rapid genomic and phenotypic changes, and unique responses to hybridization and genome doubling. While previous studies of these neopolyploids have improved our understanding of polyploidy, significant knowledge gaps remain, highlighting the need for further research into the varied impacts of whole-genome duplication on gene expression, epigenetic modifications, and ecological interactions. Notably, all of these neopolyploids have spontaneously arisen due to human activity in natural environments, underscoring the profound consequences of polyploidization in a rapidly changing world. Understanding the immediate effects of polyploidy is crucial not only for evolutionary biology but also for applied practices, as polyploidy can lead to novel traits, as well as stress tolerance and increased crop yields. Future research directions include investigating the genetic and epigenetic mechanisms underlying polyploid evolution, as well as exploring the potential of neopolyploids for crop improvement and environmental adaptation.