Publication

Queen-worker conflict can drive the evolution of social polymorphism and split sex ratios in facultatively eusocial life cycles

Quinones, A. E., Henriques, G. J. B. & Pen, I., 26-Sep-2019, In : Evolution. 14 p.

Research output: Contribution to journalArticleAcademicpeer-review

  • Andres E. Quinones
  • Gil J. B. Henriques
  • Ido Pen

Hamilton's idea that haplodiploidy favors the evolution of altruism-the haplodiploidy hypothesis-relies on the relatedness asymmetry between the sexes caused by the sex-specific ploidies. Theoretical work on the consequences of relatedness asymmetries has significantly improved our understanding of sex allocation and intracolony conflicts, but the importance of haplodiploidy for the evolution of altruism came to be seen as minor. However, recently it was shown that haplodiploidy can strongly favor the evolution of eusociality, provided additional "preadaptations" are also present, such as the production of multiple broods per season and maternal ability to bias offspring sex ratios. These results were obtained assuming no influence of workers on the sex ratio, even though worker control of the sex ratio is known to occur. Here, we model the evolution of sex-specific fratricide as a mechanism of worker control over the sex ratio. We show that fratricide can facilitate the initial evolution of helping. However, fratricide can also hamper the evolution of unconditional help. Instead, social polymorphism evolves a mixture of helping and dispersing offspring. Finally, we show that the co-evolution of sex-allocation strategies of workers (fratricide) and queens leads to a split production of the sexes, with some colonies specializing in males and others in females. Thus, the model predicts that fratricide spawns a diversity of co-existing life cycles that strongly vary in degree of sociality and sex ratios.

Original languageEnglish
Number of pages14
JournalEvolution
Early online date14-Sep-2019
Publication statusPublished - 26-Sep-2019

    Keywords

  • Altruism, co-evolution, queen-worker conflict, sex allocation, social insects, KIN SELECTION, INCLUSIVE FITNESS, ANT WORKERS, SWEAT BEE, BROOD, HAPLODIPLOIDY, BEHAVIOR, MANIPULATION, RELATEDNESS, ELIMINATION

ID: 102695336