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    • Fulltext

       

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      Permanent link:
      https://www.ias.ac.in/article/fulltext/jbsc/039/04/0609-0620

    • Keywords

       

      Body size; disruptive selection; Drosophila; fitness

    • Abstract

       

      Darwinian fitness in holometabolous insects like the fruit fly Drosophila melanogaster is reported to be positively correlated with body size. If large individuals in a population have higher fitness, then one would expect directional selection to operate leading to uniformly large individuals. However, size polymorphism persists in nature and needs further probing. We assessed the effect of body size on some of the fitness and fitness-related traits in replicate populations of genotypically large, genotypically small and phenotypically small D. melanogaster flies. In this study, the time taken to attain reproductive maturity and copulation duration were independent of fly size. Fecundity and longevity of large females were significantly higher when they partnered genotypically small males than when they were with genotypically larger or phenotypically small males. The increased female longevity when in association with genotypically small males was not due to selective early death of males that would release the female partner from presumed cost of persistent courtship. On the contrary, the genotypically as well as phenotypically small males had significantly higher longevity than large males. The virility of the genotypically small males was not significantly different from that of genotypically large males. Our results clearly show that selection on body size operates in the opposite direction (disruptive selection) for the two genders, thus explaining the persistence of size polymorphisms in the holometabolous insect, Drosophila melanogaster.

    • Author Affiliations

       

      Jaya Handa1 K T Chandrashekara1 2 Khushboo Kashyap1 Geetanjali Sageena1 Mallikarjun N Shakarad1

      1. Department of Zoology, University of Delhi, Delhi 110 007, India
      2. Institute of Excellence, University of Mysore, Manasagangotri, Mysore 570 006, India

    • Dates

       
      Published
      September 2014

  • Journal of Biosciences | News

      Forthcoming Special issue.


    • To trigger further research on plant mitochondria, the Journal of Biosciences is bringing out a special issue titled "Plant Mitochondria: Properties and Interactions with Other Organelles".


      Plant mitochondria are quite distinct and have unique features, such as a cyanide-insensitive alternate pathway. They also interact with chloroplasts to optimize photosynthetic carbon assimilation.


      Submissions are welcome until 30 July 2023. The contributions can be original articles, short communications, reviews, or mini-reviews on any topic related to plant mitochondria.


      Authors can submit their articles online at https://www.editorialmanager.com/jbsc/default2.aspx

      Posted on April 12, 2023
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