Scientists at the University of Liverpool have traced the evolution of a species of tropical butterfly, infected with a bacterium that kills males, by comparing current butterfly populations with more than 200 museum specimens.
The bacteria, called Wolbachia, are a parasitic microbe and are known to significantly alter the reproductive capabilities of a high proportion of insect species, including wasps and fruit fly.
The team found that in some butterfly populations a gene had evolved that suppresses the effects of the bacteria so that infected males survive, but in other populations in the South Pacific for example, the frequency of the bacterium varied greatly and could rise to extreme levels. The result was that the sex-ratio of a population changed rapidly from a balanced male/female population to female-biased, which can alter the butterfly's behavior and reproductive biology.
The bacteria, called Wolbachia, are a parasitic microbe and are known to significantly alter the reproductive capabilities of a high proportion of insect species, including wasps and fruit fly.
The team found that in some butterfly populations a gene had evolved that suppresses the effects of the bacteria so that infected males survive, but in other populations in the South Pacific for example, the frequency of the bacterium varied greatly and could rise to extreme levels. The result was that the sex-ratio of a population changed rapidly from a balanced male/female population to female-biased, which can alter the butterfly's behavior and reproductive biology.


