All ears and eyes

Natural History, June, 2002 by Robert (American businessman and engineer) Anderson

The senses that allow us to perceive our world are remarkably complex. But in the past decade, biologists have begun to understand how we see, hear, smell, taste, and touch. Some of the advances are highlighted (in English and Spanish) by the Howard Hughes Medical Institute at www.hhmi.org/senses/.

Take the sense of smell. Most people would say it's done with the nose. But Gordon Shepherd, a professor of neuroscience at Yale University, tells us this is "a little like saying that we hear with our earlobes." Read through "The Mystery of Smell," and you will discover that the real work is done by about a thousand different receptors on the olfactory neurons, deep inside the nasal cavity. Or read "The Quivering Bundles That Let Us Hear," and you will learn about experiments in which the cilia of the hair cells in the inner ear "quivered to the high-pitched tones of violins, swayed to the rumblings of kettle drums, and bowed and recoiled, like tiny trees in a hurricane, to the blasts of rock-and-roll." Once you know more about these amazing structures (which do not repair themselves once damaged), you might turn that music down a few decibels.

This site sparked my interest in the senses, but it doesn't have any links to other sites for more information. So I will give you one more: BioMEDIA's "Eye to Eye" annotated Web link set (ebiomedia.com/gall/eyes/EyeAWLS .html)--a great list of sites on the biology, diversity, and evolution of eyes. Be sure to check out the "Eye to Eye Gallery" at the bottom of the page.

Robert Anderson is a freelance science writer living in Los Angeles.