Effects of Wolbachia on Butterfly Life History and Ecology pp. 343-350
Authors: (Ullasa Kodandaramaiah, Dept. of Zoology, Stockholm University, Stockhom, Sweden)
Abstract: Wolbachia are intracellular bacteria found in the cytoplasm of a wide range of arthropods. They are geographically ubiquitous and estimated to infect 20-70% of all insect species. They have been in the limelight due to their fascinating manipulations of the reproductive ecology of their hosts, all of which confer a selective advantage to the bacteria by enhancing their vertical transmission efficiency. In butterflies, they induce cytoplasmic incompatibility (CI) and feminization of genetic males. They have also been known to skew sex ratios in favour of females through direct male killing. CI is caused when sperm from infected males cannot produce viable offspring with eggs of females that are not infected by the same Wolbachia strain. Some species are infected by more than one strain, resulting in complex interactions between the hosts and Wolbachia. In this chapter, I present a synthesis of current knowledge about the extent of infestation and strain diversity of Wolbachia in butterflies. I also review experimental work on male-killing, feminization and CI in different butterfly species. I discuss further challenges and future avenues of research in this field.