Evidence for no sexual isolation between Drosophila albomicans and D. nasuta
Article first published online: 3 JUN 2013
© 2013 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Ecology and Evolution
Volume 3, Issue 7, pages 2061–2074, July 2013
How to Cite
Ecology and Evolution 2013; 3(7): 2061–2074
- Issue published online: 10 JUL 2013
- Article first published online: 3 JUN 2013
- Manuscript Accepted: 1 MAY 2013
- Manuscript Revised: 22 APR 2013
- Manuscript Received: 18 FEB 2013
- National Institutes of Health. Grant Number: R01 HD060679
- cuticular hydrocarbons;
- D. albomicans ;
- D. nasuta ;
- mating behavior;
Sexual isolation, the reduced tendency to mate, is one of the reproductive barriers that prevent gene flow between different species. Various species-specific signals during courtship contribute to sexual isolation between species. Drosophila albomicans and D. nasuta are closely related species of the nasuta subgroup within the Drosophila immigrans group and are distributed in allopatry. We analyzed mating behavior and courtship as well as cuticular hydrocarbon profiles within and between species. Here, we report that these two species randomly mated with each other. We did not observe any sexual isolation between species or between strains within species by multiple-choice tests. Significant difference in the courtship index was detected between these two species, but males and females of both species showed no discrimination against heterospecific partners. Significant quantitative variations in cuticular hydrocarbons between these two species were also found, but the cuticular hydrocarbons appear to play a negligible role in both courtship and sexual isolation between these two species. In contrast to the evident postzygotic isolation, the lack of sexual isolation between these two species suggests that the evolution of premating isolation may lag behind that of the intergenomic incompatibility, which might be driven by intragenomic conflicts.