Put another way, dogs can detect some odors in parts per trillion. What does that mean in terms we might understand? Well, in her book Inside of a Dog, Alexandra Horowitz, a dog-cognition researcher at Barnard College, writes that while we might notice if our coffee has had a teaspoon of sugar added to it, a dog could detect a teaspoon of sugar in a million gallons of water, or two Olympic-sized pools worth. Another dog scientist likened their ability to catching a whiff of one rotten apple in two million barrels.
All well and good but surficants work quite well ~ but if you want to really screw up these dogs drag fried chicken all over the place ~