[Stephonovich]

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Originally Posted by viator122 First off, organic matter less than 50,000 years old can be dated pretty accurately by carbon-14 dating.

I read 30,000. But no matter. I don't place much faith in C14 dating, mainly due to the fact that we've no idea what the physical makeup of the earth was like 5,000 years ago, much less 50,000. Without knowing how much carbon was present then, it's kind of difficult to judge.

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Second, the articles say that the age of the fossils have been reinterpreted through "argon/argon radiometric dating" on the volcanic ash layers found with the fossils and geologic interpretation of the sedimentary layers. The point is that the fossils were discovered in 1967, almost 40 years ago. Methods have impoved and that's not a reason to doubt archaeology/anthropology.

I missed that part, my bad.

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Also, these people are not pointing to 195,000 years ago as the bible truth, they plainly state: "The researchers acknowledge this themselves, admitting that they cannot entirely rule out the possibility that the skulls are as young as 104,000 years old."

A deviation of 91,000 years seems a bit much to me, personally. To scale it down for the car analogy, again, that'd be like me saying it could be as early as 1876. Obviously impossible, but still. Just seems odd to me.

 

[viator122]

This website has a lot of information on carbon dating, specifically it mentions that:
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proportion of radiocarbon in the atmosphere has varied by a few percent over time

So you're right, the ration of C14/C12 does change over time, but it seems like not by a lot. The website has a lot of information on carbon-dating calibration.

As for the possible 91,000 year variation, that's what they said they couldn't rule out, not what is likely or probable. Just like our knowledge of many other sciences, this is not exact and it is a process of continual refinement, improvement of method, etc. It is also a very contentious field (like astronomy I think), so that for every scientist saying these fossils are 195,000 years old there's someone saying "195,000 years? No way, that guy probably died on Tuesday." These arguments go on and on, for decades sometimes, until a consenus is reached.

In a modern archaeological dig, certain parts are left untouched because archaeologists believe there will always be technique improvements and they want to leave something pristine to study with the new techniques.

 

[princeclassic]

Quote:

Originally Posted by Stephonovich I read 30,000. But no matter. I don't place much faith in C14 dating, mainly due to the fact that we've no idea what the physical makeup of the earth was like 5,000 years ago, much less 50,000. Without knowing how much carbon was present then, it's kind of difficult to judge.

From what I've learned of radiocarbon dating, it's quite accurate going back 40,000 years. The amount of carbon in the atmosphere does change over time, but we have records of past carbon concentration from tree ring data and undisturbed carbonate shell deposits at the bottom of certain bodies of water. Using these, the radiocarbon ratios can be calibrated and provide an accuracy that's usually within 1% of the actual date.

 

[raisin]

So Mel Brooks just keeps getting older and older...

 

[viator122]

Here's a more detailed article on the findings from the NY Times:
http://www.nytimes.com/2005/02/17/science/17human.html