Fingerprints have been used for identification purposes for a long time. They play an important role in running background checks, investigating crime scenes, and allowing access to secure facilities. All these important functions are only possible because of the uniqueness of human fingerprints. No two people have the same fingerprints, and even identical twins do not share the shame prints. This is because of the specific and unique way that the patterns on our fingers form.
The interesting lines and ridges that are present on the tips of your fingers are your fingerprints. They are friction ridges and can also be referred to as dermal ridges. Besides the fingertips, they also appear on the palms, soles, and toes. At a glance, it could seem as if everyone shares the same or similar patterns, but scientists have proved the one-of-a-kind nature of these groves extensively.
The Formation Process
Fingerprint formation takes place when the fetus is developing in the womb. This is covered in the field of developmental biology, and scientists believe that the process begins around the 10th week of pregnancy. By the time the fetus is 6 months old, the finger and toe prints are fully formed.
The exact process that creates the unique ridges and patterns is still largely a mystery, but there are some well-known and widely accepted theories about what takes place as a new human being is developing. These relate to the interactions of the three layers of the skin.
The skin is made up of two layers—the upper epidermis layer and the lower layer known as the dermis. The epidermis is further divided into two layers. These are the upper layers of the epidermis that are in contact with the external environment and the lower epidermis layer known as the basal layer of the epidermis. So, of the three layers, the basal layer of the epidermis forms the middle layer.
The most accepted theory about fingerprint formation is tied to the fact that the middle basal layer grows faster than the other two layers. It is believed that this skin layer becomes strained and scrunched up against the surrounding layers as it grows. As this continues, the pressure results in the folding of the epidermis layer into the dermis. These folds become what we know as fingerprints.
Fingerprints are formed under the top skin layer, and this makes them permanent. They do not fade as might be expected if they were formed on the very surface of the skin. Some wear does happen with use and age, but fingerprints cannot be destroyed by injuries on the surface of the fingers. People who perform repetitive physical activities such as bricklaying may find that their fingerprints are wearing off, but the ingrained prints can eventually grow back if the damage done is not too deep.
Looking at a large set of fingerprints can be a way to appreciate the beauty and uniqueness present in nature. The patterns are formed through the combination of two important contributors. These are the developmental conditions and the genetic make-up of the fetus. This means that the fingerprints are affected by DNA traits from the parents, but they are also affected by the physical conditions in the womb.
The physical or environmental conditions in the womb can be anything from the pressure that the fetal skin experiences, the supply of nutrients in the blood, and the concentration and density of the amniotic fluid in which the fetus is growing.
There are so many variables at play, and this means that even identical twins who have identical DNA have different fingerprints. Additionally, every one of your own fingerprints is completely unique.