I want to create a MDS plot with pairwise Fst values derived from a population genetics project. My Fst values are in a tab-delimited file (lower triangle only) that I view with Excel. When I use the cmdscale command I get the message: Error in cmdscale(x) : Distances must be result of dist or a square matrix In addition: Warning messages: 1: "^" not meaningful for factors in: Ops.factor(left, right) 2: "^" not meaningful for factors in: Ops.factor(left, right) 3: "^" not meaningful for factors in: Ops.factor(left, right) 4: "^" not meaningful for factors in: Ops.factor(left, right) I transformed my values using the dist command, but the resulting plot is not right. My file of Fst values are the estimates of distance that I want to directly use in the MDS analysis. Looking for help in making my Fst file read in R as a distance matrix for this to work. -Jeff DaCosta dacostaj at unlv.nevada.edu