Figure 2.

Principal Component Analysis (PCA) of larval behaviours in the M and S forms of An. gambiae in the absence of a predator. A) Principal Component 1 (PC1) shows the relationship between time spent browsing at the bottom of the container and thrashing in the middle vs. all other behaviours of 2^nd (dark grey), 3^rd (light grey) and 4^th (white) instar larvae of An. gambiae M and S molecular forms. Mean (± SE) with similar letters are not significantly different from one another (Tukey-Kramer multiple comparisons test). B) Biplot along PC2 and PC3 (mean ± SE) showing the behaviour of 2^nd (dark grey), 3^rd (light grey) and 4^th (white) instars larvae of An. gambiae M (squares) and S (circles) molecular forms.