Patterns of self-organization in ants

Ants are simple animals and their behavioural repertory is limited to somewhere between ten and forty elementary behaviours. This is an attempt to explain the different patterns of self-organization in ants.

Bifurcation
This is an instant transition of the whole system to a new stable pattern when a threshold is reached. Bifurcation is also known as multi-stability in which many stable states are possible.

Examples of pattern types:
 * 1) Transition between disordered and ordered pattern
 * 2) Transition from an even use of many food sources to one source.
 * 3) Formation of branched nest galleries.
 * 4) Group preference of one exit by escaping ants.
 * 5) Chain formation of mutual leg grasping.

Synchronization
Oscillating patterns of activity in which individuals at different activity levels stimulate one another emerging from mutual activation.

Examples of pattern types:
 * 1) Short scale rhythms arising from mechanical activation from physical contact.
 * 2) Long scale rhythms in which temporal changes in food needs and larvae stimulate changes in the reproductive cycle.

Self organized waves
Traveling waves of chemical concentration or mechanical deformation.

Examples of pattern types:
 * 1) Alarm waves propagated by physical contact.
 * 2) Rotating trails from spatial changes in food resources acting on trail laying activity.

Self-organized criticality
Self-organized criticality is an abrupt disturbance in a system resulting from a build up of events without external stimuli.

Examples of pattern types:
 * 1) Abrupt changes in feeding activity.
 * 2) Mechanical grasping of legs forming ant droplets.