> What purpose do fingerprints serve? Apart from improving our grip on objects... This has been partially debunked[1][2]: The area of skin in contact...was alw

> What purpose do fingerprints serve? Apart from improving our grip on objects... This has been partially debunked[1][2]: The area of skin in contact...was always 33% less than if the fingerpads were completely smooth. This confirmed that fingerprints do not improve our grip, because they actually reduce our skin's contact with the objects that we hold. I say "partially debunked" because it might improve grip on wet surfaces: They may allow water trapped between our finger pads and the surface to drain away and improve surface contact in wet conditions. It seems similar to the situation with tire treads. If you ask most people why tires have ridges and valleys, they'll say that it improves grip on the road. But if the road is dry, you'll get bigger contact area and therefore better grip with completely smooth tires. In fact race cars use completely smooth tires for better grip (when the racetrack is dry). Tire treads exist to conduct away water when the road is wet, and they improve grip only in that situation. In an interview with the co-author of the friction study, he made some interesting speculation about the purpose of fingerprints: My preferred theory is that they allow the skin to deform and thus stop blistering. That is why we get blisters on the smooth parts of our hands and feet and not the ridged areas: our fingerpads, palms and soles.[3] [1] http://newsvote.bbc.co.uk/mpapps/pagetools/print/news.bbc.co.uk/2/hi/health/8093134.stm?ad=1 http://newsvote.bbc.co.uk/mpapps/pagetools/print/news.bbc.co... [2] http://jeb.biologists.org/content/212/13/2016 http://jeb.biologists.org/content/212/13/2016 (actual paper) [3] http://www.manchester.ac.uk/discover/news/article/?id=4715 http://www.manchester.ac.uk/discover/news/article/?id=4715