Figure 2

Geographic distribution of the 4 house mouse species of Mus in Eurasia. The three blue blocks show the distribution of species carrying primarily Xmvs, and the yellow block marks the range of the species carrying M/Pmvs. The blue line is the Yangtze River which roughly coincides with the transition between M. castaneus and musculus [66], and the red line represents the well-studied hybrid zone separating musculus and domesticus [211]. Infectious viruses of the indicated types were isolated from mice trapped at sites indicated with arrows; not shown: the X/P-MLV virus CasE#1 isolated from a California wild mouse.