Staff from Internet giant Yahoo this week predicted that users could soon be relying on diverse body parts like ears or knuckles to authenticate themselves, with no hardware needed for enrolment except a capacitive touchscreen.In a presentation at the 2015 Computer-Human Interaction Conference (CHI) in Seoul, Yahoo researchers demonstrated an solution called Bodyprint that can scan users' ears, knuckles, palms and fingers when they are pressed against the touchscreen.Capacitive sensors in the screen map the topography of these body parts, which Yahoo says are unique to each individual.”Since all current touchscreens use capacitive sensing, Bodyprint brings reliable biometric authentication to a vast number of commodity devices. In the case that future touchscreens support higher input”, writes the research paper on the subject.A study of 12 participants had an accuracy of 99.52 percent. The research has been led by Christian Holz, a researcher in Human-Computer Interaction at Yahoo Labs, along with Senaka Buthpitiya, and Marius Knaust.”Bodyprint brings biometric authentication to commodity mobile devices using the capacitive touchscreen as a low-resolution, but large-area image sensor to reliably identify users based on their ears, fists, or grips when pressed against the touchscreen. (left) To accept an incoming call, the user places the touchscreen onto his ear. (right) Bodyprint extracts features from the raw capacitive image to identify the user.”