Article Title

Mixed Colonies in Ants

Document Type



Mixed colonies of ants, in which different species live together in a single nest and raise their young in common, are usually the result of temporary social parasitism or of slave-making activities. Temporarily mixed colonies may be produced by the invasion of an already established nest of one species by a young fertilized female (queen) of another species that is unable to start a colony independently. The brood produced by this parasitic queen is raised by the workers of the host species, whose queen may be permitted to live out her life or who may have been killed, either by her own workers or by the invading queen. The workers of the host species may die out and so leave a pure colony of the parasite (temporary social parasitism) or may be replenished by slave-making raids (dulosis, or slavery). Colonies of the slave-making species (Sanguinea group of Formica and Polyergus) are always mixed. Temporary social parasitism is represented in the genera Formica by the Rufa, Exsecta and Microgyna groups, which are temporarily parasitic on colonies of the Fusca group and of the subgenus Neoformica. Mixed nests of the latter group are very rare, but there are usually many pure colonies, of temporary parasite as well as of host species.

Publication Date


Journal Title

Proceedings of the Iowa Academy of Science





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©1949 Iowa Academy of Science, Inc.



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