Cover image

Cover Schematic organization of a metaphase chromosome according to the pattern of evolution seen in the genus Drosophila. Some regions (white) tend to participate recurrently in chromosomal rearrangements. Chromosomal segments (blue) between these fragile regions harbor blocks of genes whose organization has been conserved during evolution of related species. Taking into account the magnitude of chromosome repatterning that has occurred in this lineage, a few of these conserved blocks (orange) contain an unusually large number of genes. (Cover illustration by Marcin von Grotthuss and Art Rodar Computer Graphic Studio, http://www.artrodar.pl/prezent/onas-ang.html. [For details, see von Grotthuss et al., pp. 1084–1096.])