Someday, an enthomologist told me it was easy to modelise ants behaviour.
I tried this...

Controls :
• Get an ant out of the anthill : "n" key
• Create a batch of ants on the playground : mouse or touch drag
• Create a batch of food pieces : any key + mouse or touch drag
• Create a unique red repulsive ant : "a" key
• Make all the ants turn : keyboard arrows
• Make all ants get back to the anthill : "h"
• Make all ants stop for a short moment : "s"