Friend, foe or queen? Study highlights the complexities of ant perception

University of Illinois postdoctoral researcher Adrian Smith, right, and entomology professor Andrew Suarez found that ants are highly attuned to the chemical context of the hive. CHAMPAIGN, Ill. Researchers report that trap-jaw ants recognize the unique odor of a fertile queen only if the queen also shares the workers' own chemical cologne - a distinctive blend of dozens of smelly, waxy compounds that coat the ants' bodies from head to tarsus. The discovery offers new insights into how social animals evolved and communicate with others in their group, the researchers say. The findings, reported in Biology Letters, reveal that chemical context makes all the difference to the trap-jaw ant ( Odontomachus brunneus ), said University of Illinois postdoctoral researcher Adrian Smith , who led the study with U. of I. entomology professor and animal biology department head Andrew Suarez. "In that overall chemical profile - 40 to 50 compounds that they're producing and that coat their entire body - the ants can tell who belongs in the nest and who doesn't," Smith said. Once they recognize the distinctive blend of odors that defines their nest, the ants can sniff out the queen, who also smells of nonacosene, a universal signal of fertility in this species of trap-jaw ant.