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→T-Rex soft tissue?
:[[User:Philip J. Rayment|Philip J. Rayment]] 11:39, 29 April 2007 (EDT)
:[[User:Philip J. Rayment|Philip J. Rayment]] 11:39, 29 April 2007 (EDT)
:: Not at all. To use an analogy which came up earlier- say I have a tap measure that goes out to 10 meters. I can draw it out all the way. So if I measure how much it is drawn out I can get an answer less than 10 meters, or I can get 10 meters an answer which really means at least 10 meters. Similarly, if I get a date of about 60,000 years I know that the object is approximately at least that old. An object older than 60,000 years will in general not give a date less than about 50,000 years (this is due to the margin of error being high at the lower end of reliability). In general, carbon dating actually works best with objects that are about 2000 to 25,000 years old. The technique is reliable for a bit outside that range in both directions but the error bars become much larger and the precision of measurement required makes it difficult to perform without more specialized equipment. <small> Note that I haven't worked on C-14 dating related stuff in a while so the numbers I gave above may be slightly off, but they are close to correct </small> [[User:JoshuaZ|JoshuaZ]] 12:01, 29 April 2007 (EDT)
:: Not at all. To use an analogy which came up earlier- say I have a tap measure that goes out to 10 meters. I can draw it out all the way. So if I measure how much it is drawn out I can get an answer less than 10 meters, or I can get 10 meters an answer which really means at least 10 meters. Similarly, if I get a date of about 60,000 years I know that the object is approximately at least that old. An object older than 60,000 years will in general not give a date less than about 50,000 years (this is due to the margin of error being high at the lower end of reliability). In general, carbon dating actually works best with objects that are about 2000 to 25,000 years old. The technique is reliable for a bit outside that range in both directions but the error bars become much larger and the precision of measurement required makes it difficult to perform without more specialized equipment. <small> Note that I haven't worked on C-14 dating related stuff in a while so the numbers I gave above may be slightly off, but they are close to correct </small> [[User:JoshuaZ|JoshuaZ]] 12:01, 29 April 2007 (EDT)
The current upper limit of 60.000 years is the result of a technique [http://wwwpaztcn.wr.usgs.gov/rsch_highlight/articles/200511.html] [http://www.abc.net.au/science/news/stories/s990775.htm] developed in 2005, the research you linked to was done in 1994, when the upper limit was 35.000 to 40.000 years at best, and in case of the possibility of contamination it would have been closer to the 25.000 years Joshua pointed out.
Creationontheweb also does not provide a link to the research itself, I hypothesized a probable theory (I did say probably), but without the research itself, there is no way for me to say for certain what went wrong, although it wouldn't surprise me if the mistake has already been corrected recently, but is nevertheless still cited by creationists (see Piltdown Man).
Here is the original research used to determine whether C14-dating was useful (it links C14-dates on Egyptian mummy's among other things to corresponding historical dates) [http://www.c14dating.com/int.html].
[[User:Middle Man|Middle Man]]
==Feathers==
==Feathers==
I find it odd that one of the tenants on which CP was founded was the unreliability of wikipedia, yet a reference to an article there is used. Surely in the YECs attempt to prove evolution wrong you can do better (and by better I mean not AiG). [[User:Jrssr5|Jrssr5]] 14:52, 27 April 2007 (EDT)
I find it odd that one of the tenants on which CP was founded was the unreliability of wikipedia, yet a reference to an article there is used. Surely in the YECs attempt to prove evolution wrong you can do better (and by better I mean not AiG). [[User:Jrssr5|Jrssr5]] 14:52, 27 April 2007 (EDT)
:I wondered the same thing about the Wikipedia reference, although I did leave it there and improve it (the footnote). What's wrong with the AiG reference? (AiG is off-line at the moment, so I can't see the article to reference is to.) [[User:Philip J. Rayment|Philip J. Rayment]] 01:04, 28 April 2007 (EDT)
:I wondered the same thing about the Wikipedia reference, although I did leave it there and improve it (the footnote). What's wrong with the AiG reference? (AiG is off-line at the moment, so I can't see the article to reference is to.) [[User:Philip J. Rayment|Philip J. Rayment]] 01:04, 28 April 2007 (EDT)