Pictures (gif format)

Pictures show a greyscale representation of how many times a walker has stepped on a particular lattice site. The nest sites are in blue. Each simulation had a length of 20000 time steps and used 50 total walkers. The starting number of food was 25000, with a food per site of 100 and a food lifetime of 100. The simulations were carried out on a 200x200 square lattice.

Random Walkers: random_ps.gif
- Gaussian spread in concentration, like a random walker.

Active Walkers - Single Pheromone (minefield model):
Positive Interaction: sp_pos.gif
- Self attractive. Walkers tend to cluster and remain around nest site. As the areas around the nest site become saturated, it behaves more like random walker. If walker wanders off the path, it is generally reinforced. Notice the high distribution around the nest site.
Negative Interaction: sp_neg.gif
- Self avoiding. Walkers tend to repel one another. However as the areas become saturated, behavior tends towards more random if all surrounding sites have pheromone. The walkers which do get out tend to stay away. Notice that the distribution is spread out much more than for the positive case.

Active Walkers - Two Pheromone:
Non-Inertial: tp_ps.gif
- Start of trail formation to nearby the nest sites.
Inertial: tp_ps_inertia.gif
- Short range trail formation to a food site and back to the nest. It appears as if some of the walkers may have become "stuck" (dark islands).
Trunk Trail Inertial Walker: rnt_inertia.gif
- Weak trail formation to points nearby nest sites.
Hybrid Inertial Walker: rnw_inertia.gif
- Weak trail formation to a food site to the north-east of the nest sites.

Movie Output Files (must have AtomViewer to view; set radius = 1.0)

All movie files correspond to 500 timesteps during the above simulations. The files are written out in a format readable by AtomViewer. The walkers are shown and the nest sites are where there is a clustering of walkers in most cases.

Random Walkers: random_mov.v
- The first 500 timesteps of the simulation run. Diffuses randomly in gaussian distribution as random walker. Walkers disappear as they run into food (minefield model).

Active Walkers - Single Pheromone (minefield model):
Movie files generated from first 500 timesteps in simulation.
Positive Interaction: sp_pos_mov.v
- Self attractive. Walkers tend to cluster and remain around nest site. As the areas around the nest site become saturated, it behaves more like random walker. If walker wanders off the path, it is generally reinforced.
Negative Interaction: sp_neg_mov.v
- Self avoiding. Walkers tend to repel one another. However as the areas become saturated, behavior tends towards more random if all surrounding sites have pheromone. The walkers which do get out tend to stay away.

Active Walkers - Two Pheromone:
Here the walkers must return to the nest site with food to register a food collected. These files were taken beginning at the point in a simulation where the walkers started to collect a large ammount of food.
Non_Inertial: tp_mov.v
- Beginning to see a trail form to Southeast of the nest sites.
Inertial: tp_inertia_mov.v
- A trail is more prevalent here to the Northeast of the nest sites.
Trunk Trail Inertial Walker: rnt_inertia_mov.v
- Weak trail formation to points nearby nest sites.
Hybrid Inertial Walker: rnw_inertia_mov.v
- Weak trail formation to a food site to the north-east of the nest sites.

For more information on the different types of walker models please see our code page.