We modeled a subset of the swarm as individual bees. Each bee had an interal state (dancing, scouting, etc) as described below

  • Each bee is placed randomly on a square region, and does not move while it is with the swarm.
  • Each bee has a discrete state which depends on her history. All but a few bees start as non-scouts.
  • The few initial scouts are assigned to random nest-sites and return to the swarm at intervals and at random locations.
  • A bee can become a scout in two ways:
    1. A bee becomes a scout randomly, with fixed low probability at each time step, and is assigned to a random nest-site.
    2. A bee is within range of a dancing scout and with fixed probability becomes a scout. The new scout is assigned to the nest-site being danced for, with no error.
  • Once a bee becomes a scout for a given nest-site, she goes through a sequence of events before returning to the non-scout state. Generally, she will dance, rest, re-investigage the site, then dance for a shorter time, rest, and so on until the 'dance time' becomes zero. At that point, she reverts to a non-scout. A bee never changes the nest-site she dances for while she is a scout. Once she becomes a non-scout again, she may be recruited to any nest without bias. Details follow:
    1. As soon as the bee becomes a scout, she leaves the swarm (to 'examine' the nest-site). She evaluates the quality of the site without error, and her 'dance duration' is set to a value proportional to the site quality. She then returns to the swarm after about 40 minutes.
    2. Upon return the bee goes to a random position on the swarm and 'dances' for the site. The bee's 'dance time' is decremented and checked to see if the time is zero.
      • If it is zero, the scout reverts to the non-scout state.
      • If it is non-zero, the bee dances for the alloted time, then rests for a fixed time.
    3. In the rest state the bee is completely inactive. When the rest time is done, the bee re-investigates the same nest-site then returns to state (2) described just above.


The current version is Version14. This code is from Run 1 (R1) as described below. The simulator is a mixed, continuous and discrete-event, simulator. The time resolution in all of the results below was 6 seconds. There is an initial busrt of scouts

Each bee has an internal state as listed:

  • Is the bee alive (true/false)
  • Is the bee a scout (true/false)
  • Is the scout out of the swarm (true/false)
  • Is the scout resting (true/false)
  • The time of the next event for this bee (e.g. returns to swarm)
  • The next event type
  • Bee's x-coordinate postion in the 2D swarm (0 to 0.3 meters)
  • Bee's y-coordinate postion in the 2D swarm (0 to 0.3 meters)
  • Probability of becoming a scout (per minute) spontaneously (no prefered nest)
  • Probability of becoming a scout (per minute) when viewing a recruiting dance
  • Distance to nearest dancing scout (if any)
  • Dance duration (if any) remaining for this scout
  • Dance duration decrment per return to swarm. Fixed at 0.5 minute.
  • Dance effective range. Fixed at 0.02 meters.
  • Rest duration before revisiting a nest site. Fixed at 30 min.
  • Destination nest, if any.
  • Nest evaluation time. Each bee's value is picked from a distribution given by a gaussian with a mean of 40 min, standard deviation of 5, but with a lower bound of 20 min.

Progam logic at each time step:

  • For each bee:
    • Test to see if the bee becomes a spontaneous scout
    • Test to see if the bee becomes a recurited scout
    • Check for an event has timed out for the bee. If so:
      • Return to swarm:
        • Position the bee randomly
        • If the remaining dance duration is zero trigger an end event.
        • If the remaing dance duration is greater than zero then dance and decrement remaining dance time. Trigger a rest event.
      • Rest:
        • Wait for the rest time, then trigger a re-scout event.
      • Re-scout a nest:
        • Wait for the nest evaluation time, then trigger a return-to-swarm event
      • End being a scout:
        • Return the scout to the pool of uncommitted bees.


All tables are shown for a case with 4 nests of relative qualities 1.0,...

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