I was sitting outside the other evening with friends. Some of us had vodka drinks, others bourbon whiskey drinks. There were tiny, slow-moving flies hanging around which we noticed were always attracted to the bourbon glasses rather than the vodka glasses. Does anyone know why?
• The flies are most likely common fruit flies (). They are attracted to ripening and decaying fruit, as well as other rotting plant material. The flies are drawn by the complex aroma of esters, alcohols and carboxylic acids that ripe fruits release. Esters are a family of organic chemicals that have distinctive, sweet…
