http://xkcd.org/829/
On Thu, Dec 2, 2010 at 11:59 PM, Miles Parker <milespar...@gmail.com> wrote: > Yeah -- staying out of the name the pill controversy ;) -- one neat little > tidbit in the "I'm always amazed by how little I know and how little I've > thought about what I do know" category. We think of Arsenic as a poison, but > the only reason we think of it as a "poison" is (duh) that it is bad for > *us*, i.e. humans + every other critter that we've run into before now. But > the reason that it is bad is not that it is different from our chemistry, > like an acid, but that it is so close to our chemistry, being next to > phosphorous on the old periodic table, thus disrupting cellular mechanisms. > So while typically we think of things that are close in structure or design > to be friendly in fact here a movement to our nearest neighbor represents a > major boundary shift, while one to a distant neighbor would of course be > quite unlikely as the chances of slotting into the same role would be very > slim. That idea could certainly argue for the idea that the current six > element setup is arbitrary against some set of possible configurations. Once > a choice is made in that configuration space it would be very unlikely (and > only under these kind of extreme conditions) that we would move off it. The > fact that we can (hmm, I mean I actually probably can't so please don't > subject me to any experiments) anyway makes the argument that "because > that's the only way it works here" even more tenuous. > > > On Dec 2, 2010, at 9:21 PM, ERIC P. CHARLES wrote: > > Following Glen, Roger, and James, and also wondering why Nick is being a > pill.... > > I believe the report is of interest for showing an organism that uses > arsenic in interesting ways, but it gets its magical-shininess (i.e. Science > worthiness) for showing an organism that does not use phosphorous. We have > never found a life form that could do the "life" thing without phosphorous. It > is almost (almost) like finding an organism that uses silicon instead of > carbon. > > Oh, and then there is the potential for practical application... like > cleaning up arsenic, which is a common pollutant coming out of mines. But > anything like that is a long way off. > > Eric > > > On Thu, Dec 2, 2010 08:03 PM, *Roger Critchlow <r...@elf.org>* wrote: > > > > On Thu, Dec 2, 2010 at 4:39 PM, glen e. p. ropella > <g...@tempusdictum.com>wrote: >> >> >> [*] FWIW, I find it odd for you to ask, of this particular article, "why >> is this important?" Of all the obscure, mumbo-jumbo journal articles >> out there (our discussion of PoMo aside ;-), it seems blatantly obvious >> to me that the substitution of As for P in DNA is important, even if we >> don't know what the implications are. I am woefully ignorant of the >> literature, though. Is it fairly common to find and report substitutes >> for DNA components? >> >> No, it's not common, it's never been reported before, all DNA and RNA in > life as we have known it up until today has been based on phospho-esters. > > -- rec -- > > ============================================================ > FRIAM Applied > Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's > College > lectures, archives, unsubscribe, maps athttp://www.friam.org > > Eric Charles > > Professional Student and > Assistant Professor of Psychology > Penn State University > Altoona, PA 16601 > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org > > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org >
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org