Eusociality is a distinct form of biological organization. A key characteristic of advanced eusociality is the presence of non-reproductive workers. Why evolution should produce animals that sacrice their own reproductive potential in order to aid others is an important question in evolutionary biology. Here we provide a detailed analysis of the selective forces that determine the emergence and stability of non-reproductive workers. We study the effects, in situations where the queen of the colony has mated once or several times, of recessive and dominant sterility alleles acting in her offspring. Contrary to widespread belief based on heuristic arguments of genetic relatedness, non-reproductive workers can easily evolve in polyandrous species. The crucial quantity is the functional relationship between a colony's reproductive rate and the fraction of sterile workers present in that colony. We derive precise conditions for natural selection to favor the evolution of non-reproductive workers.
- Michael Doebeli, University of British Columbia, Canada
© 2015, Olejarz et al.
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How can natural selection favor the evolution of non-reproductive worker ants?
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