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Time in your Eyes
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Last night I watched a great reality-style documentary on the
philosopher Derrida, and was struck by something he said; that as we age, our eyes
are the only parts of our bodies that remain unchanged. I was
curious about what scientific research might be out there to support
the notion, so I googled "eyes & age" and came across an
interesting study that was conducted recently by Danish scientists.
Apparently, during the first year of life, our eyes are uniquely imprinted with a type of "time stamp"
in the form of lens proteins or crystallines. By measuring the amount of radioactive carbon-14 in the
lens, one can accurately determine a person's year of birth!
[image via leketoys]
The key to the dating process is the incorporation into the crystallines of carbon-14, which is found in all the food a person consumes. The Earth's atmosphere normally has a fairly constant level of carbon-14: it decays into nitrogen-14 with a half-life of 5,730 years, but is constantly replenished by the interaction of cosmic rays with nitrogen-14. Because it is taken up by plants, all living organisms have a concentration of carbon-14 equal to that in the atmosphere. When the organism dies, the isotope decays slowly until none of it is left -- the phenomenon that is used for radiocarbon dating of archaeological artifacts. [via LA Times]
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April 8, 2008 6:32 PM
Moshe
Derrida apparently said "as we age, our eyes are the only parts of our bodies that remain unchanged..."
Just curious what is the context, this sentence as stated is manifestly wrong, unfortunately our eyes age like all other parts of our body, this aging affects our eyesight among other things, I must be missing something...
April 22, 2008 3:55 PM
Ziya Tong
Have you had a chance to see the film Young@Heart? I'm thinking he meant it more in that vein. i.e, in the sense of a youth that resides in the eyes.
April 25, 2008 9:33 AM
Azrael Brown
This sounds like an explanation for degenerative diseases of the eye being common and not as easily preventable as others, and that there's no 'exercise' to improve eyesight...if the eye isn't growing or regenerating like hair, bones, lungs, they're going to be more succeptible to problems or inability to accomodate slow change. Time still has its effects, as well as the growth around them -- I know more than one person who has gone in and out of needing glasses as they went through puberty.
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