A Comprehensive Review on Genomics of Plant Speciation: How Hybridization and Polyploidy Drive Evolutionary Innovation

Hybridization and polyploidy are the two main evolutionary mechanisms that fundamentally drive plant speciation. With the use of contemporary genomic techniques like long-read sequencing, pangenomics, phylogenomic networks, and epigenomic profiling, these processes long acknowledged by evolutionary biologists have now been revealed in previously unheard-of detail. While polyploidy, particularly allopolyploidy, produces immediate reproductive isolation, unique gene interactions, and subgenome specialization, hybridization promotes adaptive introgression, gene flow, and the creation of hybrid species. When combined, these processes result in ecological innovation, regulatory divergence, and genetic reorganization, allowing plants to quickly diversify and colonize new habitats. This review emphasizes important case studies, summarizes genetic insights into hybridization and polyploidy, and addresses upcoming difficulties in comprehending reticulate evolution and the intricate histories of plant lineages.