Table 1. This table summarizes the main results and presents the predictions of the model
(see Fig. 4) in each case. The excitatory power (in bold) of the different navigational module
(i.e., visual matching (VM); path integrator (PI); backtracking (Ba) and systematic search
(SS)) were attributed a value between 0 and 3 according to their current situation (VM:
current view familiarity; PI: current vector length, Ba: last view seen; SS: always 1; see gray
text in Fig. 5). In all conditions, the ants were released in unfamiliar terrain so that the
excitatory power of VM is always 0. The weight of the connections (in italic) chosen for the
different module (VM: 3; PI: 2; Ba: 1; SS: 1) reflect their relative importance given the past
literature (see SI5). The predicted behavior depends on the relative influence of the different
modules.
Figure
Starting
distance
(feeder)
Travel pattern
before capture
Current
PI vector
length
Last view
seen
Observed behavior
(unfamiliar terrain)
Fig. 1
A, B
8m
8m back
0m
Nest area
Backtrack
Fig. 2
A, B
A) 8 m
B) 16 m
A) 4 m back
B) 12 m back
4m
4 m from nest
Follow PI vector
Fig. 2
A, B
A) 8 m
B) 16 m
A) 6 m back
B) 14 m back
2m
2 m from nest
Random direction
Fig. 2
A, B
A) 8 m
B) 16 m
A) 7 m back
B) 15 m back
1m
1 m from nest
Backtrack
Fig. 4
A, C
8m
8 m – 4 m, 8 m –
4 m back
0m
4 m from nest
Random direction
Fig. 4
B
8m
8 m – 4 m, 8 m –
4 m back
0m
Nest area
Backtrack
Modules hypothetical relative
influence (excitatory power ×
weight of the connection)
VM: 0 × 3 = 0
PI: 0 × 2 = 0
Ba: 3 × 1 = 3
SS: 1 × 1 = 1
VM: 0 × 3 = 0
PI: 2 × 2 = 4
Ba: 0 × 1 = 0
SS: 1 × 1 = 1
VM: 0 ×3 = 0
PI: 1 × 2 = 2
Ba: 2 × 1 = 2
SS: 1 × 1 = 1
VM: 0 ×3 = 0
PI: 0 × 2 = 0
Ba: 3 × 1 = 3
SS: 1 × 1 = 1
VM: 0 ×3 = 0
PI: 0 × 2 = 0
Ba: 0 × 1 = 0
SS: 1 × 1 = 1
VM: 0 ×3 = 0
PI: 0 × 2 = 0
Ba: 3 × 1 = 3
SS: 1 × 1 = 1