FARJI-BRENER Alejandro Gustavo
congresos y reuniones científicas
Between inefficiency and interference; individual and collective solutions
Congreso; International Union for the Study of Social Insects. XVIIIth International Congress.; 2018
One advantage of social organisms is their option to individually or collectively resolve situations that alter the normal progress of an activity (hereafter, problems). Using the trail cleaning behavior of leaf-cutting ants as model, we evaluated a conceptual model according to which cleaning strategies depend on obstacle size and shape, ant flux in the trail and trail irregularities because the effectiveness, defined as the ability to produce the result that is wanted thoroughly with no waste of time or energy (i.e. the ability to be efficacious and efficient) varies with the strategy used. We placed obstacles of different sizes and shapes, in different flux conditions and type of trails in 10 field nests of Atta cephalotes, and compared the proportion of successful removals and the removal time, as estimator of efficacy and efficiency, of removals made by one or two-three workers. We found that (1) obstacles very large could only be removed collectively which might be a consequence of individual limitations for transporting big obstacles; (2) whatever the shape of obstacles collective removals had higher probability of success but spent more time than individual removals which might be a consequence of the need of coordination among individuals participating in the collective removals; (3) whatever the ant flux ants spent more time collectively than individually, but as the ant flux increased, the probability of success increased for collective removals and decreased for individual removals which might be a consequence of a big density of foragers around obstacles increases the strength necessary to remove; and (4) trail irregularities similarly affected the effectiveness of individual and collective removals. This work highlights one of the advantages of social organisms, the option of resolving collectively those problems that exceed the individual abilities, and its associated costs: the need of coordination among society members to make a joint action