be careful where you clique
As your finger rubs over the surface of something, vibrations (corresponding to texture) are generated and sensed within your skin by Pacinian Corpuscles. These specialized nerve endings in the subcutaneous layers are equipped to receive information about pressure and frequency. So whenever anything comes along and mechanically disturbs the sensor-in-waiting, ion channels open, an electrochemical gradient forms and a signal is generated. The signal in this excited nerve ending then transmits through afferent fibers back up to your brain which helps you analyze whatever it is you’re touching.
As ridges on the skin surface, fingerprints serve to amplify vibrations for these nerve receptors by increasing surface area. Ridges also serve to increase grip, like potato chips. Apparently it’s an important skill to have as we all, to some degree or another have fingerprints. Koalas also have fingerprints.
A recent fad at Japanese Biometric weigh stations is to don someone else’s prints. Japanese Police are on the lookout for fingerprint dealers who prepare “Lee pres-on fingerprints” fashioned out of silicon tape and sold among South Koreans. The process costs about 68 yen, but for some it means turning Japanese. Not all of us can pass for Fujimoris.
Due to the presence of eccrine glands and their high density on your palms and soles (500 per sqcm), your fingerprints also say much about your diet and intake. Smoking, nutritional status, certain disease states can all be detetected when you lay down prints; But these secretions didn’t develop for the sake of ID. They’re more about keeping you thermally regulated, protecting your surface from invasion, and eliminating those metabolites your body has no use for. Thank you skin.