We all hate flies buzzing around us and spreading disease. They are capable of carrying over 100 pathogens, such as those causing typhoid, cholera, salmonellosis, bacillary dysentery, tuberculosis, anthrax, ophthalmia, and parasitic worms. Flies can’t eat solids and so they vomit on the food they land on to make it into a liquid. They also deposit faeces constantly. Ewww!
Flies also lay eggs that turn into maggots. Until the seventeenth century, the spontaneous generation of maggots in rotten meat was not associated with flies.
In 1668 the Italian physician Francisco Redi sought to demonstrate that meat does not spontaneously produce maggots. In one of the first ever controlled experiments Redi filled six jars with decaying meat. Three were closed and the remaining jars were left open. When maggots developed on the meat in the open jars, Redi believed he had demonstrated that spontaneous generation did not occur. However, supporters of the notion of spontaneous generation claimed that it was the lack of fresh air rather than the absence of flies which had prevented maggots from appearing on the meat.
Therefore, Redi undertook a second experiment, in which he covered the tops of three of the jars with muslin instead of sealing them. Once again, maggots failed to appear on the meat in the covered jars, but did appear on the meat in the open jars, where flies were able to lay their eggs.
This proved that living organisms could only arise through spontaneous generation if they arose only from other living organisms (biogenesis).
So what can you do to discourage flies?
- Flies don’t like these herbs: Basil (and Lemon Basil), Rosemary, Lavender, Bay Leaf, Mint, Tansy and Sweet Woodruff. So grow as much as you can!
- Fit bug screens to your windows.
- Keep all food and rubbish tightly covered, clean your rubbish bins with disinfectant regularly.
- Fill clear plastic bags with water and hang them at the entrance – not sure this really works but doesn’t cost much to try.
- As a general rule flying insects do not like smoke. So light an incense stick or a candle to drive them away from an area. There special candles that contain citronella that also deter certain flies.
- Buy a fly swat!