New Scientist
Image: LeGrimlin
In what could be a case of remarkably fast animal evolution, the crickets of Hawaii have begun to purr. The discovery is the latest twist in a decades-long battle between crickets and a parasitic fly that is attracted by their songs.
Male crickets usually sing to attract a mate, but this makes the Pacific field crickets (Teleogryllus oceanicus) on Hawaii easy targets for a parasite. This fly (Ormia ochracea) tracks down crickets by their songs, and deposits its maggots on them. These then burrow inside their host, killing it.
This strong incentive to stop singing meant that by around 1999, crickets on one Hawaiian island – Kaua’i – were evolving to stay silent. This was thanks to a mutation that gave males unusually flat wings, which stop them from producing a sound. By 2003, silent males made up about 90 per cent of the population – one of the fastest cases of evolution that has ever happened in the wild. Read more on newscientist.com…
