Most fingerprint scanners work the same way – the pad of the finger is pressed against the scanner’s glass surface, light is shone through the glass onto it, and the light that’s reflected back by the minuscule valleys between the print’s ridges is used to create an image of the print. It’s a system that’s usually effective, although it can fail to read prints that have been flattened by age or damaged, plus it can be fooled by gelatine casts of fingerprints. That’s why scientists from the Paris-based Langevin Institute have developed a more reliable scanner, that looks below the skin's surface.
Fingerprinting powders are still the go-to tool for investigators, both real and fictional. However, instead of oils, some fingerprints only leave a residue of amino acids and other compounds that fingerprinting powder doesn't adhere to very well. A new technique developed at Australia's CSIRO not only reveals fingerprints in cases where dusting won't, but makes them glow under UV light.
Do you remember Pig-Pen, the Peanuts comic character who's always surrounded by a cloud of his own filth? Well, it turns out that we're actually all a little like him. Scientists have discovered that not only does everyone emit an invisible "microbial cloud," but that individuals can be recognized by the bacteria that make up their particular cloud.
There are already several methods of identifying cattle –
branding, ear tags, tattooing and ear notching all come to mind. Now,
however, Egyptian scientists are working on a new biometric system that's less
invasive and more difficult to thwart: electronic muzzle-printing.