 The genus Myrmecia is among the most primitive of all known living ants , and ants of the genus are considered specialist predators . Unlike most ants , workers are solitary hunters , and do not lay pheromone trails ; nor do they recruit others to food . Tandem running does not occur , and workers carrying other workers as a method of transportation is rare or awkwardly executed . Although Myrmecia is not known to lay pheromone trails to food , M. gulosa is capable of inducing territorial alarm using pheromones while M. pilosula can attack en masse , suggesting these ants can also induce alarm pheromones . M. gulosa induces territorial alarm behaviour using pheromones from three sources ; an alerting substance from the rectal sac , a pheromone found in the Dufour 's gland , and an attack pheromone from the mandibular gland . Despite Myrmecia ants being among the most primitive ants , they exhibit some behaviours considered " advanced " ; adults will sometimes groom each other and the brood , and distinct nest odors exist for each colony . 
