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Clonal reproduction by males and females in the little fire ant


Sexual reproduction can lead to major conflicts between sexes and within genomes1,2,3,4. Here we report an extreme case of such conflicts in the little fire ant Wasmannia auropunctata. We found that sterile workers are produced by normal sexual reproduction, whereas daughter queens are invariably clonally produced. Because males usually develop from unfertilized maternal eggs in ants and other haplodiploid species, they normally achieve direct fitness only through diploid female offspring. Hence, although the clonal production of queens increases the queen's relatedness to reproductive daughters, it potentially reduces male reproductive success to zero. In an apparent response to this conflict between sexes, genetic analyses reveal that males reproduce clonally, most likely by eliminating the maternal half of the genome in diploid eggs. As a result, all sons have nuclear genomes identical to those of their father. The obligate clonal production of males and queens from individuals of the same sex effectively results in a complete separation of the male and female gene pools. These findings show that the haplodiploid sex-determination system provides grounds for the evolution of extraordinary genetic systems and new types of sexual conflict.

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Figure 1: Site and nest locations.
Figure 2: Neighbour-joining dendrogram of the genetic (allele-shared) distances between queens (Q), gynes (G) and male sperms (M) collected over all the five sites (A–E).
Figure 3

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  1. Hamilton, W. D. Extraordinary sex ratios. Science 156, 477–488 (1967)

    Article  ADS  CAS  PubMed  Google Scholar 

  2. Eberhard, W. G. Evolutionary consequences of intracellular organelle competition. Q. Rev. Biol. 55, 231–249 (1980)

    Article  CAS  PubMed  Google Scholar 

  3. Hurst, L. D. Intragenomic conflict as an evolutionary force. Proc. R. Soc. Lond. B 248, 135–140 (1992)

    Article  ADS  Google Scholar 

  4. Pomiankowski, A. in Levels of Selection in Evolution (ed. Keller, L.) 121–152 (Princeton Univ. Press, Princeton, 1999)

    Google Scholar 

  5. Hölldobler, B. & Wilson, E. O. The Ants (Springer, Berlin, 1990)

    Book  Google Scholar 

  6. Torres, J. A., Snelling, R. R. & Canals, M. Seasonal and nocturnal periodicities in ant nuptial flights in the Tropics (Hymenoptera: Formicidae). Sociobiology 37, 601–626 (2001)

    Google Scholar 

  7. Sherman, P. W., Seeley, T. D. & Reeve, H. K. Parasites, pathogens, and polyandry in social Hymenoptera. Am. Nat. 131, 602–610 (1988)

    Article  Google Scholar 

  8. Crozier, R. H. & Page, R. E. On being the right size: male contributions and multiple mating in social Hymenoptera. Behav. Ecol. Sociobiol. 18, 105–115 (1985)

    Article  Google Scholar 

  9. Cole, B. J. & Wiernasz, D. C. The selective advantage of low relatedness. Science 285, 891–893 (1999)

    Article  CAS  PubMed  Google Scholar 

  10. Pearcy, M., Aron, S., Doums, C. & Keller, L. Conditional use of sex and parthenogenesis for worker and queen production in ants. Science 306, 1780–1783 (2004)

    Article  ADS  CAS  PubMed  Google Scholar 

  11. Baudry, E. et al. Whole-genome scan in thelytokous-laying workers of the Cape honeybee (Apis mellifera capensis): central fusion, reduced recombination rates and centromere mapping using half-tetrad analysis. Genetics 167, 243–252 (2004)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Koeniger, N., Hemmling, C. & Yoshida, T. Drones as sons of drones in Apis mellifera. Apidologie (Celle) 20, 391–394 (1989)

    Article  Google Scholar 

  13. Cook, J. M. & Crozier, R. H. Sex determination and population biology in the Hymenoptera. Trends Ecol. Evol. 10, 281–286 (1995)

    Article  CAS  PubMed  Google Scholar 

  14. Simon, J.-C., Delmotte, F., Rispe, C. & Crease, T. Phylogenetic relationships between parthenogens and their sexual relatives: the possible routes to parthenogenesis in animals. Biol. J. Linn. Soc. 79, 151–163 (2003)

    Article  Google Scholar 

  15. Normark, B. B. The evolution of alternative genetic systems in insects. Annu. Rev. Entomol. 48, 397–423 (2003)

    Article  CAS  PubMed  Google Scholar 

  16. Werren, J. H., Nur, U. & Eickbush, D. An extrachromosomal factor causing loss of paternal chromosomes. Nature 327, 75–76 (1987)

    Article  ADS  CAS  PubMed  Google Scholar 

  17. Nur, U., Werren, J. H., Eickbush, D. G., Burke, W. D. & Eickbush, T. H. A ‘selfish’ B chromosome that enhances its transmission by eliminating the paternal genome. Science 240, 512–514 (1988)

    Article  ADS  CAS  PubMed  Google Scholar 

  18. Ulloa-Chacon, P. & Cherix, D. Quelques aspects de la biologie de Wasmannia auropunctata (Roger) (Hymenoptera, Formicidae). Actes Colloq. Insectes Sociaux 4, 177–184 (1988)

    Google Scholar 

  19. Rice, W. R. Sexually antagonistic male adaptation triggered by experimental arrest of female evolution. Nature 381, 232–234 (1996)

    Article  ADS  CAS  PubMed  Google Scholar 

  20. Swanson, W. J., Yang, Z., Wolfner, M. F. & Aquadro, C. F. Positive Darwinian selection drives the evolution of several female reproductive proteins in mammals. Proc. Natl Acad. Sci. USA 98, 2509–2514 (2001)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  21. Arnqvist, G. & Rowe, L. Antagonistic coevolution between the sexes in a group of insects. Nature 415, 787–789 (2002)

    Article  ADS  CAS  PubMed  Google Scholar 

  22. Helms-Cahan, S. & Keller, L. Complex hybrid origin of genetic caste determination in harvester ants. Nature 424, 306–309 (2003)

    Article  ADS  CAS  PubMed  Google Scholar 

  23. Parker, J. D. A major evolutionary transition to more than two sexes? Trends Ecol. Evol. 19, 83–86 (2004)

    Article  PubMed  Google Scholar 

  24. Chapuisat, M. Mating frequency of ant queens with alternative dispersal strategies, as revealed by microsatellite analysis of sperm. Mol. Ecol. 7, 1097–1105 (1998)

    Article  Google Scholar 

  25. Fournier, D. et al. Characterization and PCR multiplexing of polymorphic microsatellite loci for the invasive ant Wasmannia auropunctata. Mol. Ecol. Notes 5, 239–242 (2005)

    Article  CAS  Google Scholar 

  26. Raymond, M. & Rousset, F. GENEPOP (version 1.2): population genetics software for exact tests and ecumenicism. J. Hered. 86, 248–249 (1995)

    Article  Google Scholar 

  27. Page, R. D. M. TreeView: an application to display phylogenetic trees on personal computers. Comput. Appl. Biosci. 12, 357–358 (1996)

    CAS  PubMed  Google Scholar 

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We are grateful to the Laboratoire Environment de Petit Saut (EDF-CNEH) for hosting us during field work, the Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD) of French Guiana for allowing access to plantations, S. Aron for performing flow cytometry analysis, and M. Chapuisat, P. Christe, D. Haig, R. Hammond, S. Helms Cahan, K. Parker and D. Queller for comments on the manuscript. The work was supported by grants from the French Ministère de l'Écologie et du Développement Durable to A.E. and the Swiss NSF to L.K.

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Correspondence to Denis Fournier or Arnaud Estoup.

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Fournier, D., Estoup, A., Orivel, J. et al. Clonal reproduction by males and females in the little fire ant. Nature 435, 1230–1234 (2005).

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