The origin of species, or speciation, the "mystery of mysteries", as Charles Darwin called it, is an issue at the very heart of evolutionary biology, critical to understanding the mechanisms behind the great diversity of life around us. This book is centred around three major research areas: (1) biodiversity patterns in relation to speciation scenarios; (2) mechanisms that produce pre- and postzygotic reproductive isolation and adaptive divergence; as well as (3) genetics, epigenetics, and genomics of speciation. Being a mishmash of new ideas, reviews, conventional and nonconventional case studies, this collection demonstrates more than anything how research can benefit from integration of traditionally divergent disciplines, such as biogeography, paleontology, taxonomy, molecular genetics, proteomics, and genomics.