Introgression is emerging as an important source of novel genetic variation, alongside
standing variation and mutation. It is adaptive when such introgressed alleles are …

Intrinsic postzygotic barriers can play an important and multifaceted role in speciation, but
their contribution is often thought to be reserved to the final stages of the speciation process …

The origin of biological diversity, via the formation of new species, can be inextricably linked
to adaptation to the ecological environment. Specifically, ecological processes are central to …

The emerging field of speciation genomics is advancing our understanding of the evolution
of reproductive isolation from the individual gene to a whole-genome perspective. In this …

Hybrid zones are, roughly speaking, narrow regions in which genetically distinct populations
meet, mate, and produce hybrids. They are often only a few hundred meters wide and yet …

Wolbachia is an endosymbiotic Alphaproteobacteria that can suppress insect-borne
diseases through decreasing host virus transmission (population replacement) or through …

Levels of genetic differentiation between populations can be highly variable across the
genome, with divergent selection contributing to such heterogeneous genomic divergence …

Hybridization may influence evolution in a variety of ways. If hybrids are less fit, the
geographical range of ecologically divergent populations may be limited, and prezygotic …

Many species are divided into a mosaic of genetically distinct populations, separated by
narrow zones of hybridization. Studies of hybrid zones allow us to quantify the genetic …

Hybrid zones are currently of interest because they offer experimental material for studies of
the characters and processes involved in divergence and speciation. Parapatric su6species …