Bacteria collective motion

From bird flocks to the human gathering, and from colonies of army ants to swimming bacteria, collective behaviors happens all the time.

According to Tamás Vicsek et al.,[1] collective behavior refers to the phenomenon that an individual unit’s action is dominated by the influence of the ‘‘others’’.

When flagellated bacteria are moving in bulk liquid, where the locomotion of one individual doesn’t affect the others, this movement is called swimming.

At a moist surface or in a thin liquid film, flagellated bacteria will exert another pattern, which is called swarming motility.

[2] Bacteria swarming refers to a rapid cellular bacterial surface movement powered by rotating flagella.