Tuesday, 17 June 2014

Silencing of the crickets: rapid evolution in response to deadly flies

Scientists in the School of Biology, along with researchers from Edinburgh and the USA, have have published a new study on the rapid evolution of wild crickets from predominantly loud, chirping males to silent males in approximately one decade on two islands in Hawaii. Typically, male crickets attract females with their songs by rubbing their wings, which have a sound-producing file and scraper, together. However, parasitic flies use the sound of male songs to find the crickets and deposit baby maggots on their backs. The maggots burrow in and eat the crickets alive as they grow.

Some male crickets in Hawaii have silenced their songs because of a mutation that erases the file and scraper on their wings. Interestingly, these ‘flatwing’ mutations have happened independently, about two years apart, on both the islands of Kauai and Oahu. This convergent evolution is rarely observed at such evolutionary speed in the wild and is an excellent opportunity to look at this phenomenon in its earliest stages. The team, including Dr Sonia Pascoal, Prof. Michael Ritchie, and Dr Nathan Bailey, next hope to identify the mutations responsible for the changes.
[Full article: http://dx.doi.org/10.1016/j.cub.2014.04.053]BBC News story]