Why doesn't he find out the answer for himself? You can't expect the "scientists" to have answers to every single question about biological organisms. What I suggest the gentleman does is capture a sample of flies, and, carefully controlling for variables such as draughts and temperature fluctuations, introduce them individually into his room, and time how long they manage to fly without stopping. He should plot his results on a graph , and send them in to the Independent. Not only will he be enlightening readers about a subject we knew nothing about, but he will be demonstrating that the spirit of independent inquiry is not dead among the British after all.