The mean inbreeding coefficients found for Minami-cho (366 couples) and Shinsei-cho (511 couples) were 0.00307 and 0.00191, respectively. The mean inbreeding coefficient decreased and the mean marital distance increased as the year of marriage becomes more recent. The mean distances and their standard deviations between birthplaces of mates, father-offspring, mother-offspring, and sibs are 69.05 ± 229.64, 73.09 ± 246.66,49.81 ± 158.43, and 39.53 ± 159.51 km, respectively, at Minami-cho. These values are 188.45 ± 387.05, 187.79 ± 562.59, 148.26 ± 326.35, and 73.93 ± 225.92 km, respectively, at Shinsei-cho. The dimensionality of migration is closest to one di