A study by Joseph R. Coelho showed that during territorial patrolling the species had a high and regulated thorax temperature. Experiments found that the wasp has the ability to shift heat from its thorax to its abdomen and that the abdomen is generally kept colder than the thorax. Dead wasps that were placed in the sun reached abnormally high temperatures when compared to those on nearby plants. Life cycle Emergence and mating After hatching, the offspring feed on the tissue of the cicadas provided by their mother. Males emerge before females and both genders are sexually receptive from emergence in July to early August, when they mate and brood. English naturalist Charles Darwin postulated that the pattern of male emergence before females evolved by natural selection to improve the chances of the male mating. The timing of the emergence of females has evolved to correspond with the similar emergence of the cicada species of the area, Tibicen duryi and T. parallela, which they hunt for the provisioning of their nests. Many have yellow markings located on their tergites (dorsal portion), although some have been found only from the first to fifth tergites. Because males emerge earlier than females, the males compete for mating territories surrounding the nests in which the females are located. During a fight, the males risk damaging their wings or appendages by butting and grappling. Another defense technique is to grab another male and carry it high into the air, which is thought to be a demonstration of strength. As a general rule, the larger the male the more predominant he is in battles. Age influences the success in the defense and security of territory; the younger the wasp the greater the chance of a successful takeover of territory. Some small males even engage in non-territorial mating tactics, and delay their emergence so as to have a fairer chance of survival. On emergence from the nest, the female is sexually receptive but does not choose her mate, but instead copulates with the first male of her species that finds her. Once the female has mated, she rebuffs all advances by other wasps. Nesting and perching Males perch after emerging from their nest. They pick out an area close to a nest with females inside and guard the territory around it so as to have a better chance of mating. They tend to perch on many different substrates