Wednesday, January 23, 2008

The Potentially Oldest Human Skull Fossil Found

An almost complete human skull fossil that could date back 100,000 years was unearthed in Henan last month, Chinese archaeologists announced Tuesday.
"It is the greatest discovery in China after the Peking Man and Upper Cave Man skull fossils were found in Beijing early last century, and will shed light on a critical period of human evolution," said Shan Jixiang, director of the State Administration of Cultural Heritage.

You can read more here.

Some questions:
-How do we know we can trust the dates ascribed to Fossils?
-Are there instances where a fossil was found but it was known to be of a different date than what was assigned to it?
-Can humans be 100,000+ years old?
-Are they referring to micro-evolution in the statement above?


pastorbrianculver said...

I think the only time on fossils I would trust would be the ones from

Roland said...

Is carbon 14 dating flawed?

j razz said...

First, plants discriminate against carbon dioxide containing 14C. That is, they take up less than would be expected and so they test older than they really are. Furthermore, different types of plants discriminate differently. This also has to be corrected for.2

Second, the ratio of 14C/12C in the atmosphere has not been constant—for example, it was higher before the industrial era when the massive burning of fossil fuels released a lot of carbon dioxide that was depleted in 14C. This would make things which died at that time appear older in terms of carbon dating. Then there was a rise in 14CO2 with the advent of atmospheric testing of atomic bombs in the 1950s.3 This would make things carbon-dated from that time appear younger than their true age.

Measurement of 14C in historically dated objects (e.g., seeds in the graves of historically dated tombs) enables the level of 14C in the atmosphere at that time to be estimated, and so partial calibration of the ‘clock’ is possible. Accordingly, carbon dating carefully applied to items from historical times can be useful. However, even with such historical calibration, archaeologists do not regard 14C dates as absolute because of frequent anomalies. They rely more on dating methods that link into historical records.

The above was taken from this link

That is one view.

Apparently Atomic Mass Spectroscopy is a lot more reliable. I will leave this to Bill at Physics Ramblings though as he is way more the expert than I.

j razz

pastorbrianculver said...

Wow, I thought I had witnessed a genius in the making!! I am glad there are other people who are able to discern truths in science!

B Nettles said...

"plants discriminate against ...14C"
Wow. I wonder if he means all or some. It would have been interesting to see an actual scientific reference for that study. I seriously doubt that discrimination against (or for) 14C is more than 1/1000 if that large. This is a quick estimate based on what the hyperfine splitting measurements of atomic energy levels of C13. Hyperfine splitting means that the energy level is 4.000007 units instead of 4.000005 units. It's very measurable with sophisticated instrumentation, but makes close to zero difference in metabolic chemical reactions. It's like saying that the octane in your gasoline that has 14C has a different burn rate than the octane with 12C or 13C.

"ratio...has not been constant" It's interesting that the examples given have all been within the past 200 years. 14C dating isn't used for objects in that period.

The article doesn't state what method was used to date the skulls. Are there other articles that do tell?

When using any radiometric dating technique you have to be concerned with contamination and try to get some self-calibration markers. Carbon contamination is especially easy since carbon-12,13,and 14 is around us continually. Plus due to the halflife of 14C, getting anything beyond 50000 years has been a problem. Better technology is allowing an extension of the because neutron activation (bombarding a sample with neutrons) and Fourier transform mass spectroscopy (which allows for measuring miniscule amounts of specific isotopes) is giving us much better data than we had 15-20 years ago.