The source of the cichlid images used in the graphic accompanying Tom Tregenza and Roger K. Butlinrs “Speciation without isolation” (Nature 400, 311–312; 1999) should have been acknowledged as a photograph taken by Michael K. Oliver. The photograph of the species concerned, Dimidiochromis compressiceps, and others can be viewed at The Cichlid Fishes of Lake Malawi, Africa http://www.connix.com/mko