Humans are considered to have a poor sense of smell. However, when parents are presented with baby clothing, they are able to identify the clothing with which their own infant had been in contact with a high degree of accuracy. Specially trained individuals, such as wine and perfume testers, are able to identify large numbers of different kinds of molecules that the average person cannot identify. Birds rely primarily on sound and sight for information about their environment; they have a poor sense of smell. Most mammals are known to have a very well-developed sense of smell. Is it possible that we have evolved into sound-and-sight-dependent organisms like birds and have lost the keen sense of smell of our ancestors? Or is it that we just don't use our sense of smell to its full potential? Can you devise an experiment that would help shed light on this question?

What would indicate that humans have the ability to smell things but do not use that ability?

To devise an experiment you should take into account such things as the following: Should you use one person or a large number of different people? What kinds of odors should you choose to use in your experiments? Does the number of molecules of the compound(s) chosen make a difference? What will be the control and experimental situation? Can the experiment be repeated many times? Should you expect individual variation among different people? How will you prevent people from trying to "give you the right answer"?