Figure 2.

Proportion of trunk-ants or leaf-ants that were re-sighted working on the same tasks as on the previous day, in relation to colony-size parameters (n = 17 colonies). Re-sighting of an ant performing the same task is a measure of behavioural specialization. The specialization of trunk-ants increased with number of (a) tree spines, (b) workers and (c) tree diameter. Leaf-ants were not more specialized (d) in trees with more spines, nor (e) in colonies with more workers, nor (f) in trees with greater trunk diameter. Correlations of foraging specialization with number of spines and workers are statistically significant when excluding the largest colony (see text).