Comments on: Fingerprints and Grip – Wrong vs Incomplete

By: johns224

johns224 — Mon, 29 Jun 2009 16:21:23 +0000

Steve, where did you get the bit about “…behaves more like rubber – where friction is mainly a function of surface area, not the force of contact.”?

I’m pretty sure that friction is simply a measure of force times coefficient of friction, rubber or not.

http://www.worsleyschool.net/science/files/tires/andfriction.html

By: Zelocka

Zelocka — Tue, 16 Jun 2009 20:00:29 +0000

Or it could just be that finger prints do nothing useful and are just a leftover of evolution that didn’t make enough of a difference to bother getting rid of. Just because we have something doesn’t mean it has to be useful. Sure I can keep spare change in my appendix and wag my tail nub when I am happy but that’s just me.

By: artfulD

artfulD — Tue, 16 Jun 2009 16:05:32 +0000

Here’s a link to the original paper:
http://ethomas.web.wesleyan.edu/wescourses/2004s/ees227/01/spandrels.html

And a good follow-up link:
http://en.wikipedia.org/wiki/Spandrel_(biology)

And to really feel good:
http://www.online-literature.com/voltaire/candide/

By: gfb1

gfb1 — Tue, 16 Jun 2009 13:54:46 +0000

i haven’t read the original paper… but, (and i know i dredge up the past…) anyone who works in this area (i.e., adaptation and evolution) should read, digest, then read-again gould&lewontin’s classic paper.

http://www.ncbi.nlm.nih.gov/pubmed/42062

do it; you’ll feel better

By: YairR

YairR — Mon, 15 Jun 2009 12:09:55 +0000

“the Earth is really an oblate spheroid and slightly larger in the Southern hemisphere”

It also pulsates with the tides.

By: JimV

JimV — Sun, 14 Jun 2009 22:43:47 +0000

The last time I read an article on nanotribology, several years ago (I think in “Scientific American”), it was presented that in fact friction is always poportional to contact area, rather than contact force, but that in harder materials, such as steel, an increase in contact force compresses microscopic ridges, increasing the actual contact area. So the high-school physics rule of thumb that friction force equals a coefficient times the normal force is just a convenient shortcut, not the primary physical relationship.

Which has nothing to do with the main point, other than perhaps as something else the media got wrong or glossed over.

By: Febo

Febo — Sat, 13 Jun 2009 13:09:56 +0000

The Isaac Asimov article mentioned by Bigfrozenhead was succinctly summarized in a recent episode of The Big Bang Theory, when someone said, “It’s wrong to say that a tomato is a vegetable, but it’s REALLY wrong to sat that it’s a suspension bridge.”

By: sonic

sonic — Sat, 13 Jun 2009 06:29:27 +0000

(I am a reformed headline writer.)

It is important to note that many headlines are written by ‘headline writers’- not the author of the article.
The job of the headline writer is to come up with some short phrase that will provoke emotion in the reader. The headline writer may or may not actually read the article that he is writing the headline for.

Anytime a story has complexity (as with economics, science, politics…) the difference between the headline ane the article can be large.

Facts to aid in the evaluation of information in the modern age.

By: bigfrozenhead

bigfrozenhead — Fri, 12 Jun 2009 21:55:30 +0000

A great essay dealing with the whole concept of wrong vs. incomplete is "The Relativity of Wrong" by Isaac Asimov. Highly recommended.

By: artfulD

artfulD — Fri, 12 Jun 2009 16:56:31 +0000

Fingerprints, more accurately, finger ridgings, serve the primary purpose of tactile discernment. They allow the fingers to act as a probing mechanism, which was arguably the first type of sensory apparatus developed by life forms. Like all sensory apparatuses, they help us uncover important information about the nature of our surroundings. For humans, they help the fingers tell us something about what a substance consists of that our eyes, ears, and noses, etc., cannot completely do.

Why are they all necessarily different? I suppose partly because there’s no necessity for them all to be the same.