Figure 1. Experimental setups for ethograms and choice experiments.

(A) Setup for observations on individual workers while excavating in soil and depositing pellets. Observations of individually marked workers were done both inside the clay arena, where soil pellets were excavated, and in the depositing box, where the most pellets were deposited. (B) Setup for choice experiments to test the influence of deposited pellets on the workers' decisions where to excavate. The motivation segment was connected to the subcolony to stimulate ants to excavate at that location, while soil pellets from the excavation box were placed at one side in the observation segment for the subsequent choice situation. After replacing the motivation segment with the observation segment (inset), it was observed at which side the ants started to dig first.