Ergonomics of load transport in the seed harvesting ant Messor barbarus Linnæus, 1767: morphology influences transportation method and efficiency

We studied in the field the load transport behavior of workers of the polymorphic Mediterranean seed harvester ant Messor barbarus Individual ants used two different methods to transport food items: carrying and dragging. The probability of dragging instead of carrying varied significantly with both the mass of the item transported and its linear dimension. Moreover, the values of item mass and length at which dragging began to occur increased...