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Scientists Wonder What Fingerprints Are For
Hugh Pickens writes "The BBC reports that scientists say they have disproved the theory that fingerprints improve grip by increasing friction between people's fingers and the surface they are holding. Dr Roland Ennos designed a machine which enabled him to measure the amount of friction generated by a fingerprint when it was in contact with an acrylic glass at varying levels of pressure. The results showed that friction levels increased by a much smaller amount than had been anticipated, debunking the hypothesis that fingerprints provide an improved grip. Ennos believes that fingerprints may have evolved to grip onto rough surfaces, like tree bark; the ridges may allow our skin to stretch and deform more easily, protecting it from damage; or they may allow water trapped between our finger pads and the surface to drain away and improve surface contact in wet conditions. Other researchers have suggested that the ridges could increase our fingerpads' touch sensitivity."
I noticed this at the zoo watching a bunch of monkeys swing from branch the branch in a cage. The tree branches they had been given had been worn smooth through long use and every time a monkey grabbed on to a smooth branch I felt a jab in my fingers in sympathy. There is something bad about grabbing a smooth object and relying on it to save your life.
So maybe finger prints improve grip with smooth timber surfaces. Testing against glass doesn't sound very realistic. We didn't evolve to grip glass. Or maybe (as the summary suggests) it is something to do with detecting the texture of a surface to find a place to grip.
Of course they don't ask why people have unique finger prints. Maybe it evolved to make murderers easier to catch.
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It's obvious fingerprints were designed by our creator to help the Police catch murderers.
I also love how they never counterweight their centrifuges.
Throughout history, there have been lots of questions that science has not been able to answer. But science is not static. Over time, it has been able to answer more and more questions and close more and more of the 'gaps.'
For any theist, the 'God of the Gaps' defense is pretty weak. Just because we don't understand something doesn't require a God (or gods) to explain it.
This is not a rejection of theism, but simply a comment on science - just because we don't have an answer now doesn't mean we won't have an answer in the future. And not having an answer does not imply that there is a (or many) God(s).
Agreed. I'm not a scientist and to me the answer is as obvious as it is to you.
It is clearly a case of aliens genetically modifying the species to easily identify individuals; we do the same in tagging wildlife.
They use auto-balancing centrifuges.
Wanna fight ? Bend over, stick your head up your ass, and fight for air.
Sorry.
I'll get my coat.
In a survey of 100 programmers, 111111 thought that duck-typing was a good idea.
There is a fair amount of evidence that they increase tactile sensitivity. We have nerves that are sensitive to specific vibrational frequencies. As fingerprints run over edges, then generate vibrations at frequencies we have maximal sensitivity for.
http://www.sciencemag.org/cgi/content/abstract/323/5920/1503
"Other researchers have suggested that the ridges could increase our fingerpads' touch sensitivity."
:/)
from TFA (sorry i can figure out how to use the quote function
how is this not obvious? where he have some sort of ridge like pattern (hands, feet) we have more sensitive nerves there. The ridges increase surface area of our skin which means we can feel more using up less volume
the star nosed mole is the perfect example of increased surface area for more touch sensitivity.
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Careful with "purpose" -- Evolution is non-teleological, and "purpose" has no place in evolutionary explanations. I think you mean that everything has to ba adaptive, but even then I wonder how you know -- surely evolution would allow characteristics that are not adaptive as long as they have no cost. In fact, evolution depends to some extent on things that are not necessary, as Stephen J Gould pointed out -- a part of an organism can only adapt to a new function if it's not needed for something else.
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The USA's National Public Radio show, "Science Friday" discussed this:
http://www.npr.org/templates/story/story.php?storyId=105310429&ft=1&f=5
The show talks about this result, and reveals that New world monkeys have similarly ridged
skin on the gripping side of their tails. Touch sensitivity, and resistance to blistering are
posited as potential answers.
More grip, larger surface, which means more flexibility, more nerve-endings - more sensitivity, better warmth-exchange, 'folded-up-ness', which means more protection from wounds, easier to clean (like footprints, the mud just falls out), 'little bits that stick out' - meaning more sensitivity again.
Religion is what happens when nature strikes and groupthink goes wrong.
With articles such as this, it's hard to tell whether we're being subjected to bad science or bad journalism. Both the summary and TFA quite categorically state that the "myth" of fingerprints being used to improve grip has been disproven. They then go on to describe how this experiment tested whether fingerprints helped when grasping an extremely smooth surface, and found out that they didn't (well okay, actually they did, but not by very much).
Finally, some alternate hypotheses as to why fingerprints evolved are posited, the first of which is: they may improve grip on rough surfaces. Not acrylic glass or anything, but those other kind of surfaces - you know, the type that actually occur in nature.
I'm pretty sure I don't know much more now than I did before I read the article.
Or a population of primates that happened to have fingerprints became dominant for some other reason.
It is often the case that an environmental shift makes an existing trait advantageous (that trait may have been meaningless in the previous environment), rather than an advantageous trait arising in a static environment.
Nerd rage is the funniest rage.
If we have fingerprints, it's genetically possible to be born without, so it's very likely that that mutation existed in the history of evolution, and that one of those specimen procreated, creating that fingerprint-less type of monkey/man.
I would actually question to what extent this is a possibility. Human skin has all sorts of textures and patterns, most of which we don't treat with any significance. It may be that smooth skin is actually difficult to produce by biological processes. This is a possibility that should at least be considered.
"Welcome to our world. We are the wasted youth. And we are the future too." Yes, I know these are stupid lyrics.
Picking your nose seems like a good enough reason.
Some drink at the fountain of knowledge. Others just gargle.
Other than that they serve no other purpose, like wasps.
Hey, if it weren't for WASPs, who would shop at The Gap or Banana Republic? Who would buy purse-sized dogs? And who would keep psychotherapists and badminton set manufacturers in business?
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Most atheists explain it as "I won't believe until I see proof of it", though, which is very much scientific.
Although that seems like a good idea at first, if the treatment was powerful enough to remove his fingerprints, it could have caused some nerve damage as well, which could cause his diminished sensitivity. However, if he (and other such people) were to submit to tests and scans and general research, they would surely prove helpful in deciphering the mystery of the fingerprint.
I've had the experience of having no fingerprints for a time. I worked at UPS unloading trucks; one of the customers shipped many thousands of small boxes just before the end of the year; the boxes were the precise size that the only way to grip them was with the pads of fingers and thumb (I'm looking at you, Daytimers!). A large portion of those boxes passed through my hands. Shortly after I started work there, I noticed that I was having trouble gripping items that were wet - a water glass with condensation on it would routinely slip through my fingers. When I examined my hands I saw that the ridges of my fingerprints were basically worn away. I wore gloves for a bit while working and the problem cleared itself up.
Another illustration would be to look at the skiving on the bottom of a pair of deck shoes. On a dry surface, they offer no advantage whatsoever, but on a wet surface the difference in grip is remarkable. Or for that matter tire treads - a set of slicks is the absolute best way to maximize grip - unless it's wet, at which point they become the WORST configuration.
"As God is my witness, I thought turkeys could fly." A. Carlson
Perhaps they helped attract mates?
Naturally ribbed, err... fingers, for her pleasure?
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