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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."
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.
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.
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.
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.
Yes we did. The better you can hold your glass, the more alcohol you are able to drink. The more alcohol you drink, the more likely you are to end up with some ugly girl who also was able to drink herself unconscious.
Now imagine that you would drop your glass before you are at that point. You would never be drunk enough to go with THAT girl and she won't go home with YOU.
Without fingerprints, we would be extinct by now.
Don't fight for your country, if your country does not fight for you.
most evolutionary features get kept that do not kill the person/animal having it, and which does not put it at a disadvantage in reproducing. There are many more evolved features that do nothing that have been kept than you think.
Exactly -- why does it have to be for any particular use? More likely it's just an artifact of how skin develops. People forget that many traits didn't evolve for a specific purpose, but rather, were random mutations that were not selected against, becauee they did the species no harm.
The whole question also shows a profound ignorance of the rest of the animal kingdom:
Dogs have noseprints that are as unique as fingerprints (and in fact are legal ID for dogs in Canada). Why is this? Probably no reason at all, other than quirks of individual cell layout in the skin layer.
Chickens have similar uniqueness in the surface of their combs. Why? Likewise, probably no reason, other than it's just a trivial quirk of how the skin cells piled up in a given individual.
~REZ~ #43301. Who'd fake being me anyway?
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