Why do we grow fingerprints? What is the biological meaning of fingerprints?

On December 26th, according to foreign news media, a man, named Thomas Jennings, fled the scene in 1910 after the attack, but he left a complete fingerprint on the railing outside the crime scene, which led to his conviction in 1911.
this is the first time fingerprint identification has been used as evidence in criminal investigations.
since then, fingerprinting has been cited as a key piece of evidence in criminal investigations.
Because everyone's fingerprint recognition is unique, fingerprint recognition is undoubtedly a great crime-breaking tool, it's like a special purpose for this.
but that is certainly not the case.
so the question is: Why do we grow fingerprint recognition? What is the biological significance of fingerprint recognition? In fact, scientists have been arguing about the answer to this question. According to Roland Ennos, a biomechanics researcher and visiting professor of biology at the University of Hull in the UK,
, there are two ideas about fingerprinting: one is that it helps to increase friction in grip, and the other is that it helps to enhance touch.
Ennos has spent her first research on the first idea that fingerprint recognition can enhance our grip.
for a long time, the theory has been dominant in the idea that the fine grooves of fingerprint recognition can create friction between the hand and the surface of the object.
fingerprint recognition may function similar lying like rubber tires in a car.
rubber is naturally flexible and fits well to the ground.
, the pattern of the grooves on the tyre increases the surface area of the tire, further enhancing its friction and grip.
this may support the idea that fingerprint recognition enhances fingertip friction.
, Ennos conducted validation in the lab. "We wanted to see if fingerprint recognition would enhance the friction between the fingertips and the contacted surface, like a tire pattern, "
. "To find out, the researchers placed an plexiglass plate between the fingertips of the subjects' hands, applied forces of varying sizes to them, and used the mud to determine the area of contact between the fingertips and the glass, "
.
and the results were surprising: because the gap of fingerprint recognition did not touch the glass, fingerprint recognition reduced the area of contact between the fingertip and the glass.
in other words, fingerprint recognition seems to reduce friction compared to smooth skin in the rest of the body, at least for smooth surfaces.
, Mr. Ennos points out, does not completely overturn the theory that fingerprint recognition enhances grip.
perhaps fingerprint recognition increases friction between the fingertips and the surface of the object in wet conditions, just as the pattern of a tire can be drained by a capillary action.
but this view is harder to verify because it is difficult to accurately simulate the performance of human fingerprint ingress under such conditions.
But don't forget, there's another point of view.
subtle touch a few years ago, a biologist at the University of Paris, whose full name is Georges Debr?geas, suddenly became interested in the role of touch as he pondered the reasons why humans had fingerprint recognition.
our fingertips are distributed with four mechanical receptors, cells that respond to mechanical stimuli such as touch.
de Bregias is particularly interested in one of the all-named Pacinian corpuscles.
the receptor is located about 2 mm below the skin of the fingertip. "The reason I'm interested in it is that we've learned from previous experiments that these receptors can regulate the perception of fine textures, "
.
", "These mechanical receptors are particularly sensitive to faint vibrations at frequencies of 200 Hz, and thus give the fingertips a high sensitivity.
de Bregias wondered whether fingerprint recognition reinforced this sensitivity. to find out
, he and his colleagues designed a bionic tactile sensor that mimics the structure of a human finger and is equipped with a Pasini-like small body that can detect faint vibrations.
they produced two versions, one with a smooth surface and the other with a trench-like structure similar to human fingerprint recognition.
the two devices from the same surface, the researchers were surprised to find that the trench structure on the second device could amplify the vibration of a particular frequency, and the Pasini-style small body is the most sensitive to the vibration of that frequency.
suggests that human fingerprint recognition may also be able to screen for vibrations at specific frequencies and pass the filtered vibrations to the mechanical receptors beneath the skin.
theory is that by amplifying this fine sensory information, fingerprint recognition can enhance our tactile sensitivity.
as Debregias puts it: "Fingerprint recognition on the skin has completely changed the nature of these tactile signals.
", what good is this super-sensitive fingertip? For thousands of years, our hands have been a key tool for helping us forage, eating, and exploring the world, tasks that need to be accomplished with touch.
from an evolutionary perspective, sensitivity to texture is particularly important because it helps us find the right food, distinguishes the food that can be imported from the food in question, and prevents us from eating something that is rotten and spoiled.
de Bregias also noted that this fingerprint recognition is also "paired" with Pasini-style small bodies in animals such as chimpanzees and koalas that need to be foraged with sensitive touch.
but he stressed that these experiments do not prove that fingerprint ingestion evolved for these purposes.
But the theory is persuasive, as if "everything is right".
in fact, Debregias believes that humans may have evolved fingerprint recognition for both purposes.
"We are so good at manipulating and grasping objects because we have a great sense of touch that forms an ongoing feedback loop between what we touch and our feelings, helping us to adjust the force of our fingers on the object in real time."
", for example, if you take something in your hand and slip, you need to feel the change in the surface of the object with your sensitive fingertips to catch it.
so de Bregias believes that our ability to grip with fine touch and precision is actually complementary and co-evolved.
Ennos also offers another possible explanation: fingerprint recognition may prevent long blisters from the fingertips.
fingerprint-identified trench-shaped structure may in some direction swell the skin, inhibit blister production, but also allow the skin to stretch at a specific angle, with the surface of the object to maintain contact, a bit similar to the reinforced tire used in the steel cord.
so what's the final conclusion? At this stage, apart from providing the police with nail-biting evidence of crime, the purpose of fingerprinting remains a mystery to us.
Source: Sina Technology.