A NOVEL MECHANISM FOR JUMPING IN THE INDIAN ANT HARPEGNATHOS SALTATOR(JERDON) (FORMICIDAE, PONERINAE)

The Indian ant Harpegnathos saltator may be unique among insects in us ing its jumping capacity not only as an escape mechanism but also as a normal means of locomotion, and for catching its prey in flight. High -speed cinematography used to analyse the various phases of the jump s uggests that Harpegnathos employs a novel jumping mechanism to mediate these behaviours: namely the synchronous activation of its middle and hindlegs. Electrophysiological recordings from muscles or nerves in p airs of middle and hindlegs show remarkably synchronous activity durin g fictive jumping, supporting the synchronous activation hypothesis. H arpegnathos is not the only ant to jump, and a cladistic analysis sugg ests that jumping behaviour evolved independently three times during a nt evolutionary history.