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Why does carbon dating detect when things were alive? How are the atoms in living things any different from the atoms in dead things?

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  Why does carbon dating detect when things were alive? How are the atoms in living things any different from the atoms in dead things? Sam Wormley <swormley1@gmail.com> - 2015-10-22 16:34 -0500
    Re: Why does carbon dating detect when things were alive? How are the atoms in living things any different from the atoms in dead things? jimp@specsol.spam.sux.com - 2015-10-22 22:00 +0000

#527523 — Why does carbon dating detect when things were alive? How are the atoms in living things any different from the atoms in dead things?

Why does carbon dating detect when things were alive? How are the atoms 
in living things any different from the atoms in dead things?
> http://www.askamathematician.com/2013/12/q-why-does-carbon-dating-detect-when-things-were-alive-how-are-the-atoms-in-living-things-any-different-from-the-atoms-in-dead-things/


> Physicist: As far as carbon dating is concerned, the difference
> between living things and dead things is that living things eat and
> breathe and dead things are busy with other stuff, like sitting
> perfectly still.  Eating and breathing is how fresh 14C (carbon-14)
> gets into the body.


> Our atmosphere is brimming over with 14N.  Nitrogen-14 has 7 protons
> and 7 neutrons, and is about four fifths of the air you’re breathing
> right now.  In addition to all the other reasons for not hanging out
> at the edge of space, there’s a bunch of high-energy radiation
> (mostly from the Sun) flying around.  Some of this radiation
> sometimes takes the form of free neutrons bouncing around, and when
> nitrogen-14 absorbs a neutron it sometimes turns into carbon-14 and a
> spare proton (“spare proton” = “hydrogen”).
>
> This new 14C gets thoroughly mixed into the rest of the atmosphere
> pretty quickly, and carbon in the atmosphere overwhelmingly appears
> in the form of carbon dioxide.  It’s here that the brand-new 14C
> enters the carbon cycle.  Living things use carbon a lot
> (biochemistry is sometimes called “fun with carbon”) and this carbon
> enters the food chain through plants, which pull it from the air.
> Any living plant you’re likely to come across is mostly made of
> carbon (and water) it’s absorbed from the air in the last few years,
> and any living animal you come across is mostly made of plants (and
> other animals) that it’s eaten in the last few years.
>
> With the notable exception of the undead, when things die they stop
> eating or otherwise absorbing carbon.  As a result, the body of
> something that’s been dead for around 5700 years (the 14C half-life)
> will have about half as much 14C as the body of something that’s
> alive.  Nothing to do with being alive per se, but a lot to do with
> eating stuff.



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#527536

Sam Wormley <swormley1@gmail.com> wrote:
> Why does carbon dating detect when things were alive? How are the atoms 
> in living things any different from the atoms in dead things?

Dead things don't eat or breathe so they don't get any new atoms, shit head.

Have you ever wondered what your life might have been like if you had
the competence to do more than just copy the words of others, spamming
piece of shit?

-- 
Jim Pennino

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