Smell is a duplicitous sense, simultaneously straightforward and mysterious. First it tells us the toast is burning and then it resurrects faint recollections from childhood. From our distant ancestors we have acquired hardwiring to certain smells and our response to them is reflexive but to many others we learn a response that includes the emotions, memory, and the endocrine system. The more we understand about our sense of smell, the more we have to redefine its true function. In popular belief it is a warning system: bad smells indicate spoiled food, gas leaks, and other hazards. But while the existence of bad smells is easy to explain, there is, to date, no satisfactory biological reason for good smells. It may be that our very survival depends upon our ability to distinguish between “good” genes and “bad” genes, and it appears we do this by smell.
Tim Jacob earned a degree in biochemistry from Sussex University and a Ph.D. in biophysics from the University of East Anglia. His research interests include smell acquisition, smell’s effect on behavior, smell hedonics, psychophysiological responses to smell, olfactory function measurement, pheromones, and smell’s contribution to flavor. He has written or contributed to over 75 papers, which have appeared in journals such as Physiology and Behavior, Neuropsychopharmacology, Clinical Neurophysiology, Journal of Physiology, and Chemical Senses and in books such as Signals and Perception (2002) and Art and the Senses (2011). Outside his research, he maintains leading websites on smell and taste and frequently contributes to radio and TV. His work has been funded by the Medical Research Council, the Wellcome Trust, and the Royal Society.