Forensic Science: Everything You Need to Know

As previously mentioned, there are three main types and six subtypes of fingerprints. Those are plain arch, tented arch, plain whorl, central pocket whorl, double-loop whorl, accidental whorl, radial loop and ulnar loop.

A plain arch starts on one side of the print, flows up, and then down, and exits on the opposite side of the print. A tented arch is similar to the plain arch, except there is a noticable increase in the middle, resembling a support pole holding up a tent. Neither of these arches have deltas.

A plain whorl is a print that appears to be in the form of a never-ending loop, similar to a black and white hypnosis wheel. The central pocket whorl is a pattern that appears to have a dot in the middle, resembling a hurricane eye on a weather forecast. The double-loop whorl is a pattern that appears to have two loops interconnected with each other. An accidental whorl is one that takes the shape of a kidney bean. All of these whorls have two deltas, except for the accidental whorl, which has three deltas.

A radial loop is a pattern type that enters on one side, recurves, and exits on the same side. The opening of the loop faces toward the thumb, so it called the radial loop. A second reason is that the radius bone is on the same side as the thumb. An ulnar loop takes the same pattern formation, except the opening faces the side of the little finger, which is also the side with the ulna bone. Both of these loops have only one delta.

There three types of prints found at a crime scene. Those are latent, patent, and plastic prints. These are all left behind at a crime scene, due to sweat and oils secreted from the sweat glands on our palms.

A latent print is a two-dimensional print that is left on a surface that allows the print to become invisible to the naked eye. A patent print is also two-dimensional, but it is seen in blood. A patent print is three-dimensional and can be found in mud, soap bars, and even butter.