Sympatric Speciation through Intraspecific Social Parasitism

• Published in: Proceedings of the National Academy of Sciences - PNAS 2003-06, Vol.100 (12), p.7169-7174
• Main Authors: Savolainen, Riitta, Vepsäläinen, Kari
• Format: Article
• Language: English
• Subjects: Animals; Ants; Ants - genetics; Ants - parasitology; Ants - physiology; Base Sequence; Bayes Theorem; Biological Evolution; Biological Sciences; Biological taxonomies; DNA, Mitochondrial - genetics; Ecology; Ecosystem; Evolution; Female; Host-Parasite Interactions; Inquilinism; Male; Models, Biological; Molecular Sequence Data; Parasite hosts; Parasites; Phylogeny; Queen insects; Social Behavior; Social parasitism; Speciation; Species Specificity; Sympatric species; Topology
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1036825100

Sympatric speciation through intraspecific social parasitism has been proposed for the evolution of Hymenopteran workerless parasites. Such inquilines exploit related host taxa to produce their own sexual offspring. The relatedness of inquilines to their hosts has been generalized in Emery's rule, suggesting that social parasites are close or the closest relatives to their host species. If the closest relative of each parasite is its host, then multiple independent origins of the parasite species are implied even within a single genus, probably through sympatric speciation. To test the plausibility of sympatric speciation in inquilines, we conducted a mitochondrial DNA phylogenetic analysis in three inquiline-host pairs of Myrmica ant species. We show that congeneric inquilines have originated independently several times. We also show that two of the inqulines are more closely related to their hosts than to any other species. Our results suggest sympatric speciation of Myrmica inquilines. Sympatric speciation is probably facilitated by the social biology and ecology of Myrmica, with polygyny as a prerequisite for the evolution of intraspecific parasitism.