Journal of Genetics

, 80:1

Evolution of faster development does not lead to greater fluctuating asymmetry of sternopleural bristle number inDrosophila

  • Mallikarjun Shakarad
  • N. G. Prasad
  • M. Rajamani
  • Amitabh Joshi
Article

DOI: 10.1007/BF02811412

Cite this article as:
Shakarad, M., Prasad, N.G., Rajamani, M. et al. J Genet (2001) 80: 1. doi:10.1007/BF02811412

Abstract

Both strong directional selection and faster development are thought to destabilize development, giving rise to greater fluctuating asymmetry (FA), although there is no strong empirical evidence supporting this assertion. We compared FA in sternopleural bristle number in four populations ofDrosophila melanogaster successfully selected for faster development from egg to adult, and in four control populations. The fraction of perfectly symmetric individuals was higher in the selected populations, whereas the FA levels did not differ significantly between selected and control populations, clearly indicating that directional selection for faster development has not led to increased FA in sternopleural bristle number in these populations. This may be because: (i) development time and FA are uncorrelated, (ii) faster development does result in FA, but selection has favoured developmentally stable individuals that can develop fast and still be symmetrical, or (iii) the increased fraction of symmetric individuals in the selected populations is an artifact of reduced body size. Although we cannot discriminate among these explanations, our results suggest that the relationship between development time, FA and fitness may be far more subtle than often thought.

Keywords

sternopleural bristledevelopmental stabilityevolutioncanalizationfluctuating asymmetryDrosophila melanogaster

Copyright information

© Indian Academy of Sciences 2001

Authors and Affiliations

  • Mallikarjun Shakarad
    • 1
  • N. G. Prasad
    • 1
  • M. Rajamani
    • 1
  • Amitabh Joshi
    • 1
  1. 1.Evolutionary Biology Laboratory, Evolutionary and Organismal Biology UnitJawaharlal Nehru Centre for Advanced Scientific ResearchJakkur, BangaloreIndia
  2. 2.Poornaprajna Institute of Scientific ResearchBangaloreIndia