Ants work both individually and collectively

http://www.independent.co.uk/environment/nature/ants-have-unique-ability-to-switch-between-individual-and-collective-action-says-study-10425367.html

"Ants have an almost unique ability among animals to switch between individual and collective action, according to new research which uncovers the mystery behind their impressive teamwork.

The insects are able to transport objects such as food that are much larger than themselves by intuitively understanding when to be part of the collective muscle and when to play an individual 'scouting' role for the group, researchers found.
Experiments using the Cheerios breakfast cereal showed how groups of a dozen or more ants working in unison could haul much bigger items by pushing in the same direction. But crucially, when the group moves off-course or trouble looms, the ant who first realises the problem transforms into a highly individualistic leader."

This is pretty cool. There is really no leader. there is one ant who is in the best position to give directions at that time.