The multi-dimensional nature of information drives prioritisation of private over social information in ants

When personally gathered and socially acquired information conflict, animals often prioritise private information. We propose that this is because private information often contains details that social information lacks. We test this idea in an ant model. Ants using a food source learn its location and quality rapidly (private information), whereas pheromone trails (social information) provide good directional information, but lack reliable information about food quality. If this lack is indeed responsible for the choice of memory over pheromone trails, adding information that better food is available should cause foragers to switch their priority to social information. We show it does: while ants follow memory rather than pheromones when they conflict, adding unambiguous information about a better potential food source (a 2µl droplet of good food) reverses this pattern, from 60% of ants following their memory to 75% following the pheromone trail. Using fluorescence microscopy, we demon...