How is it that a fly always seems to be buzzing around your food moments after you sit down for an outdoor meal?
The answer is practice. Or, more specifically: evolution. Flies and other insects have been on a multimillion-year journey of evolution, honing their ability to detect food. Being able to zero in on nutritious meals is a matter of life and death.
The family of flies that I study – the blow flies – are the buzzing ones that are usually a beautiful metallic blue, with bronze and green colors. They’ve perfected their ability to quickly sense the smells that naturally come off picnics and trash cans because they are a source of food for their offspring, also known as maggots.
