page_title: Red harvester ant
section_title: Caste system
hierarchical_section_title: Red harvester ant / Division of labor / Caste system
caption_attribution_description: I took this photo showing the barren nature of a red harvester ant mound.
context_page_description: Pogonomyrmex barbatus is a species of harvester ant from the genus Pogonomyrmex. Its common names include red ant and red harvester ant. These large ants prefer arid chaparral habitats and are native to the Southwestern United States. Nests are made underground in exposed areas. Their diets consist primarily of seeds, and they consequently participate in myrmecochory, an ant-plant interaction through which the ants gain nutrients and the plants benefit through seed dispersal. Red harvester ants are often mistaken for fire ants, but are not closely related to any fire ant species, native or introduced.
context_section_description: Red harvester ants are eusocial insects, characterized by a high level of cooperation and an organized division of labor. The worker caste is sterile. As with most ant species, reproduction is performed by a mating caste that consists of winged alates (reproductives) that reside in the nest until weather permits them to fly away and mate. After copulation, the male usually dies, while the now-fertilized queen returns to the ground to search for a suitable nesting site. Once she has chosen a site, she sheds her wings and begins to reproduce, creating a new colony. She produces "worker ants" for 1–20 years until her death. Some queens have been known to live up to 30 years in the wild.
  In P. barbatus, reproductive and nonreproductive tasks are divided into a caste system, as discussed above. Some individuals are specialized for reproductive function, while other ants are responsible for nonreproductive roles such as defense, caring for the brood, and foraging for food. The system of division of labor naturally arises in conjunction with the formation of the group, rather than as a secondary adaptation; otherwise solitary queen harvest ants placed in forced association had division of labor arise in groups that lack an evolutionary history of such social arrangements.
caption: Red harvester ant nest entry
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