Almost everyone in the world carries a unique ID with them at their fingertips. These are their fingerprints. It is a swooping spiral pattern on the fine ridges of the skin on the pads of the fingers. No two people have the same fingerprints. Nor are they identical twins. That's why some mobile phones can be unlocked at the user's fingertips. And why are fingerprints left at crime scenes useful in identifying criminals?
Fingerprints are formed before birth. The pattern starts at her three spots on each fingertip: under the nail, in the middle of the pad of the finger, and in the crease of the first knuckle of the finger. The design of a fingerprint is determined by how the skin ridges spread out and fuse from these three spots. A person's fingerprints can spread slightly throughout their lifetime. However, the overall pattern remains the same.
When someone touches an object, it can leave a fingerprint on that object. This mark can be made of oil, dirt, or other substances on a person's skin. Forensic scientists have long collected such fingerprints from crime scenes. These traces can provide clues about who was at a particular location and what they did there.
Investigators can't always find the right culprit through fingerprints. Criminals have been wiping fingerprints from objects at crime scenes to cover their tracks. Additionally, it was difficult to determine whether fingerprints found at crime scenes were left by the perpetrator or at another time. But new research makes fingerprint evidence even more reliable.
One team has discovered a way to detect wiped fingerprints. This technology is based on the fact that chemicals in human fingerprints corrode metal surfaces. Corrosion can be detected even if the printed matter is not visible. Other scientists have discovered ways to estimate age from fingerprints. They do this by observing the chemicals in fingerprints that change over time due to interaction with air. This can reveal whether the fingerprint dates from the time of the crime or before or after the crime.
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How fingerprints are formed is no longer a mystery A mathematical theory proposed in the 1950s helps explain this process. (2023/5/10) Readability: 7.3
Were those fingerprints left at the time of the crime?A new test may provide the answer. In a potential boon for forensic science, chemists have identified a way to date fingerprints. (2023/1/11) Readability: 7.3
Forensic scientists have an advantage when it comes to crime. Advances in technology can reveal hidden fingerprints and help identify missing people. (2022/12/22) Readability: 6.7
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Each person’s fingerprints are unique and last a lifetime. But are fingerprint patterns random, or do people inherit their characteristics from their parents? If fingerprint patterns are inherited, pairs of siblings are more likely to have similar fingerprints than pairs of unrelated people. This experiment from Science Buddies lets you find out if that’s true.
Source: www.snexplores.org
