Figure 4.

Principal component analysis (PCA) of CHC profiles obtained from single workers. Workers differ systematically, depending on treatment and are aligned on different axes. PCA reveals that the amounts of components integrated into the CHC profile within particular sub-colonies are variable. Ellipses represent 95% confidence areas. Blue: 11 workers of sub-colony 0, yellow: 12 workers of sub-colony A, red: eight workers of sub-colony AB, green: seven workers of sub-colony C. Gray arrows indicate loadings for the same 13 hydrocarbons as in Table 1.