Characteristics of CHC composition of F. yessensis.

(A) Gas-chromatogram of CHCs of F. yessensis. (B) Discriminant analyses of individual CHC profiles among four nests within the “Ishikari supercolony”; (C) Discriminant analyses of individual CHC profiles among three independent nests: “Hoshioki” (H) within and “Oshoro” (O) and “Hakkenzan” (Ha) outside the “Ishikari supercolony”. (D) Correlation between geographic distance and the Mahalanobis distance (average±SE) between the 4 nests within the “Ishikari supercolony”; (E) Correlation between geographic distance and the Mahalanobis distance (average±SE) between the three independent nests. For the discriminant analyses in (B) and (C) we used 24 peaks (A-X) that were commonly detected in all tested individuals, but omitted the 25th compound, Y, having a too high molecular mass to be chemically identified (see Table 1). The straight lines in (D) and (E) are regression lines drawn by the least-squares method.