I always liked this shot and I had a little fun thinking about it’s meaning. 
(Please don’t take me seriously!)

The first ant is Haru. Because he’s the silent leader. 
Makoto follows Haru with a distance between them, because Makoto knows Haru needs his personal space. 
Then there are Nagisa and Rei, walking side by side like the married couple they are. 
Next is Rin. He makes himself the outsider in Season one, so he keeps a distance from the group with a grumpy little ant-face. 
And then there is Sousuke. He got lost on the way a few times, but he’s on a good way to catch up to the others for Season 2. You go, Sousuke!!