• Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/jgen/082/03/0095-0113

    • Keywords

       

      directional asymmetry; Drosophila subobscura ; fluctuating asymmetry; geometric morphometrics; isochromosomal lines; Procrustes analysis; wing shape; wing size

    • Abstract

       

      Fluctuating asymmetry (FA) is often used as a measure of underlying developmental instability (DI), motivated by the idea that morphological variance is maladaptive. Whether or not DI has evolutionary potential is a highly disputed topic, marred by methodological problems and fuzzy prejudices. We report here some results from an ongoing study of the effects of karyotype, homozygosity and temperature on wing form and bilateral asymmetry using isochromosomal lines ofDrosophila subobscura. Our approach uses the recently developed methodologies in geometric morphometrics to analyse shape configurations of landmarks within the standard statistical framework employed in studies of bilateral asymmetries, and we have extended these methods to partition the individual variation and the variation in asymmetries into genetic and environmental causal components. The analyses revealed temperaturedependent expression of genetic variation for wing size and wing shape, directional asymmetry (DA) of wing size, increased asymmetries at suboptimal temperature, and a transition from FA to DA in males as a result of increase in the rearing temperature. No genetic variation was generally detected for FA in our samples, but these are preliminary results because no crosses between lines were carried out and, therefore, the contribution of dominance was not taken into account. In addition, only a subset of the standing genetic variation was represented in the experiments.

    • Author Affiliations

       

      Pedro Fernández Iriarte1 Walkiria Céspedes1 Mauro Santos1

      1. Grup de Biologia Evolutiva (GBE), Departament de Genética i de Microbiologia, Universitat Autónoma de Barcelona, Bellaterra, Barcelona - 08193, Spain
    • Dates

       
  • Journal of Genetics | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.