for me, i like the 3rd and 4th pic.
3rd pic, somehow, u managed to get many of the ant's heads in focus. also i agree with titan, that this pic feel lively. very "mother nature".
i cant explain why i like the recce pic. maybe its the colour contrast and composition. altho there's quite a lot of empty space, i think the space gives a nice feel to the pic as a whole. feels a bit like those inspirational posters sold in bookstores. wasted not the whole ant is in focused.