Speciation, the evolution of reproductive isolation among populations, is continuous,
complex, and involves multiple, interacting barriers. Until it is complete, the effects of this …

Darwin's theory of sexual selection fundamentally changed how we think about sex and
evolution. The struggle over mating and fertilization is a powerful driver of diversification …

In recent years, scientists have realized that evolution can occur on timescales much shorter
than the" long lapse of ages" emphasized by Darwin—in fact, evolutionary change is …

The transition from 'well-marked varieties' of a single species into 'well-defined species'—
especially in the absence of geographic barriers to gene flow (sympatric speciation)—has …

As populations diverge, genetic differences accumulate across the genome. Spurred by
rapid developments in sequencing technology, genome-wide population surveys of natural …

Speciation is a fundamental evolutionary process, the knowledge of which is crucial for
understanding the origins of biodiversity. Genomic approaches are an increasingly …

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 …

Personality differences are a widespread phenomenon throughout the animal kingdom. Past
research has focused on the characterization of such differences and a quest for their …

Most speciation events probably occur gradually, without complete and immediate
reproductive isolation, but the full extent of gene flow between diverging species has rarely …

Hybridization has many and varied impacts on the process of speciation. Hybridization may
slow or reverse differentiation by allowing gene flow and recombination. It may accelerate …