POSTPHARYNGEAL GLAND SECRETION AS A MODIFIER OF AGGRESSIVE-BEHAVIOR IN THE MYRMICINE ANT MANICA RUBIDA

The role of postpharyngeal gland secretion in nestmate recognition was tested in Manica rubida. Behavioral tests comprised two consecutive e ncounters between five ants and their color-marked nestmate. The first encounter utilized an untreated ant constituting a control, whereas i n the second encounter the marked ant was treated with postpharyngeal gland exudate. Scoring was done using an aggression index obtained by direct observation and an agitation index deduced from a frame-by-fram e analysis of videotapes of the various tests. When the glandular secr etion originated from an alien ant, the ants became very agitated and were aggressive toward their nestmate. When the exudate originated fro m a nestmate, the ants generally remained calm, although their rates o f self-grooming increased.