Genome Organization, Evolution of

Tests of hypotheses about the evolutionary forces that act on chromosomal structure variation are now possible with the availability of extensive complete genomes. This article provides overviews of the types of chromosomal variation found within and between species and of the evolutionary hypotheses that have been proposed to explain the karyotypic variation. Karyotypic diversity within species can limit the ability to shuffle allelic variation in the genome during meiosis, thus, acting as modifiers of recombination. The modification of recombination may be a leading cause for why karyotypes vary within and between species.