Sympatric

Sympatric species occupy the same or overlapping geographic ranges. When two closely related species are sympatric, they typically show character displacement — exaggerating morphological differences in the area of overlap to reduce competition or reproductive interference (ecological character displacement and reproductive character displacement). Sympatric speciation (speciation without geographic isolation) is controversial but has been documented in several fish species, including cichlids of the African Great Lakes where new species have evolved in the absence of physical barriers through disruptive selection on colour patterns or feeding morphology.