Social isolation of mature workers affects nestmate recognition in the antCamponotus fellah

This study investigates the role of social stimulation on nestmate recognit ion in mature workers of Camponotus fellah. We isolated 4-week-old workers before examining their behaviour in dyadic reunion tests. At the age of 4 w eeks, workers are normally intolerant towards both allospecific and homospe cific but allocolonial individuals. However, when they were isolated for up to 20 days, allocolonial aggressions decreased while allospecific aggressi on remained constant. Workers isolated for 20 days also engaged in allocolo nial trophallaxis. These results suggest that workers need to be reinforced by social stimulation during their adult life to keep precise nestmate rec ognition capacities. We discuss our data under the perspective of recent ne uroethological data in social insects to propose a mechanism for the format ion of the neural template used in the nestmate recognition process. (C) 20 01 Elsevier Science B.V. All rights reserved.