Fig. 2.

Mean of differences (with 95% confidence intervals) in ant and beetle density or species richness between noncultivated vegetation and adjacent cotton fields, for nonTr, Bt, and BtHr cotton. (a and b) Ant density (a) and ant species richness (b) declined significantly from noncultivated vegetation to cotton fields. (c and d) Beetle density (c) and beetle species richness (d) increased significantly from noncultivated vegetation to cotton fields, except for species richness in Bt cotton. For ants, the year did not affect overall changes in density (P = 0.99) or species richness (P = 0.39) from noncultivated vegetation to the cotton types, nor the differences among changes in density (P = 0.98) or species richness (P = 0.13) in the cotton types. Similarly for beetles, the year did not affect overall changes in density (P = 0.85) or species richness (P = 0.73) from noncultivated vegetation to the cotton types, nor the differences among changes in density (0.64) or species richness (P = 0.96) in the cotton types.