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A common response to seeing an ant in your house is to stamp on it. But if you crush a member of the ant species? , you might catch a hwiff of strange  smell, a smell that reminds some people of blue cheese, rancid butter or rotten coconut¹. In fact the smell is so noticable that the insect's common name is the odorous house ant, and many people call it the coconut ant. In an effort to figure out why people have these reations, researchers enlisted² visitors at an event called the North Carolina Bug³ Fast. One hundred and forty-three volunteers smelled smashed ants and were asked to identify the scent⁴ from four choices, blue cheese, rancid butter, rotten coconut or just other. All the websites overwhelmingly call the smell rotten coconut. Almost forty percent of the human judges picked  blue cheese and about twenty-five percent picked rotten  coconut, more than thirty percent went with  the choice of other. The scentists then analysed the chemicals responsible for the ant odor as well as the smelly chemicals in blue cheese, fresh coconut and coconut buried underground for three days. It turns out the chemistry of the ant scent is indeed similar to that of the blue cheese and rotten coconut, but not to fresh coconut. And researchers note that  the  penicillin microbes that turn coconut oil rancid are also involved in the production of blue cheese. The study is in the journal America Entomologist. The researchers also noted⁵ that the most common right candidate as a prescription⁶ for the ants' aroma⁷ was cleaning spray, and one little girl told them that the ants, " smelled exactly like her doctor."