The Aims of Artificial Life : Emergence

The concept of emergence is absolute fundamental to the premises of ALife. Many examples of emergence can be found in nature. Emergence is the fact complex behaviour arises without an overall controller responsible for coordinating the behaviour of the group as a whole.

Evidence of emergent behaviour can be seen from many examples in our world:

1. A Flock of Birds
   How do large flocks of birds fly through the air as a collective unit?
   Contrary to popular opinion there is not actually any 'lead' bird who gives instructions. Each bird follows a set of, if you like, preprogrammed instructions, which cause them to flock.

2. Claping after a concert or play
   Not convinced? Well when the audience shows its appreciation, (generally) no one is telling the people what rhythm to clap, and yet quickly the audience all claps in time..

3. Ant Colonies
   An ant colony of 500 000 ants can:
   • Form a nest of their bodies that regulate temperature to within one degree.
   • In a single day the colony can raid 200m through a trophical rain forst.
   • Form efficient teams for the purpose of transporting large items of prey.
   • Communicate with each other over the most efficient path to take when travelling towards food.
   The next page explains how some of these feats can be accomplished without an overall controller..

4. Traffic Jams
   Sure some traffic jams are caused by accidents, but what about those times where you're stuck in traffic, you figure there's been an accident and yet when you drive on a way, it clears and fortunately no accident has happened?
   No one has told the traffic to slow down, it just does. Some ALifers have modelled traffic jams, and found it is just one of those emmergent behaviours that occurs without any seemingly good explaination. For more on this see http://www.theo2.physik.uni-stuttgart.de/treiber/MicroApplet/.