 In a 2011 study which investigated the causes of ant sting anaphylaxis in Australia, 265 of the 376 human participants reacted to the sting of several "Myrmecia" species.Of these, nine serum samples taken from patients were IgE positive to the venom of "M. regularis".These ants are both diurnal and nocturnal, foraging on the trunks of "Eucalyptus" trees to feed on sap and nectar, or capturing small insects (such as caterpillars and ants in the genus "Camponotus" or subgenus "Orthocrema").