Generality
Fingerprints are literally defined as " mark left by fingertips on a smooth surface, used as a means of personal identification ".
The dermatoglyphics are nothing but the set of the crests and furrows present on the fingertips of the hands and which take different forms from individual to individual.
In truth, strictly speaking, dermatoglyphics are also present on the palms of the hands and on the plants and on the toes. However, in most cases, it is those present on the fingertips of the hands that are used as a means of recognition to identify an individual and distinguish him from another. Not surprisingly, the morphological differentiation of fingerprints is believed to be largely due to hereditary and genetic factors.
Characteristics of Fingerprints
Fingerprints can be used as a means of individual recognition thanks to their interesting features, such as:
- Individuality, that is, fingerprints are characteristics and unique for each individual, so much so that even the homozygotic twins - although they possess an identical chromosomal kit - have different fingerprints. However, it is worth remembering that this characteristic is attributed to fingerprints only on the basis of empirical data, since it has not yet been scientifically proven. On the other hand, such a scientific demonstration is, logically speaking, rather difficult to carry out, if not impossible.
- Immutability, since fingerprints are formed in the fetus, approximately around the eighth month of pregnancy and from that moment on, they no longer vary throughout the life of the individual. The only variation that the footprints can undergo is that relative to their dimensions which, of course, will tend to increase in adulthood.
If the skin of the fingertips is injured, it is healed and the skin is regenerated with the same morphological characteristics it had before the lesion. However, in some cases, scars (which are still visible and identifiable) could alter the morphology of the fingerprint permanently.
- Classification . The grooves and crests that make up fingerprints can take on different conformations, giving rise to different patterns. However, the possible variations are rather limited and this allows a systematic classification of the aforementioned schemes to be carried out.
Classification
As stated above, fingerprints can be classified according to the (limited) patterns that the ridges and furrows draw on the fingertips.
First of all, the fingerprint can be divided into three different areas that have specific lines:
- Basal zone, located near the line between the second phalanx and the fingertip. Normally, the lines of the basal zone are parallel to the above mentioned line spacing;
- Marginal zone, whose lines outline the fingertip in its apical part, in the radial part and in the ulnar part;
- Central area - otherwise known as the core of the imprint - which is located in the center of the fingertip and is delimited by the lines present in the other areas.
The lines formed by the crests on the surface of the fingertips can then assume different conformations, thus giving rise, substantially, to four different figures, named in the following way:
- Adelta ;
- Monodelta ;
- Bidelta ;
- Compound .
However, the classification and recognition of fingerprints are complicated procedures, which require considerable preparation.
The study - which includes both the relief and the examination of fingerprints - is called fingerprinting .
Purposes
As mentioned, fingerprints are mainly used as a means of personal recognition and their use is now known to recognize and identify criminals by law enforcement and security organs.
However, fingerprints are not only used in criminology, but can also be used in other sectors, such as:
- Anthropology, for ethnic systematics;
- Legal medicine;
- Human genetics, for example, to make the diagnosis of zygotic in twins.
Furthermore, in some cases, fingerprints can be used in the medical field for the detection of some pathologies. In fact, it seems that some forms of dermatoglyphs may be closely related to some chromosomal aberrations, such as the one that characterizes Down syndrome.
