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Henry J



Posts: 4014
Joined: Mar. 2005

(Permalink) Posted: Mar. 19 2010,15:06   

I vaguely remember that place...

  
FrankH



Posts: 525
Joined: Feb. 2009

(Permalink) Posted: Mar. 19 2010,17:03   

As I can't yet start a new thread and I can't find one that seems to address this issue, one of the "best evidences" he ahas against evolution is that Humans are unique.  One of the traits is our curiosity.  Our curiosity, it was stated, goes against evolution as fear means we should be afraid of everything.

What I replied as a rebuttal is that not everything can be seen as a danger in the beginning.  It is the perceived threat vs the chance to gain food, shelter, etc that need to be weighed against the other, especially for a species that has replaced a great deal of instinct with intelligence.

I think that sort of backfired as he then stated that the loss of instinct in humans shows we were designed as well.

Any ideas?

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Marriage is not a lifetime commitment, it's a life sentence!

  
Henry J



Posts: 4014
Joined: Mar. 2005

(Permalink) Posted: Mar. 19 2010,17:13   

First thing that comes to mind is that loss of instinctual behavior is simply a side effect of the gain in intelligence, and the hard wired instincts that are still present are now being overridden some of the time.

  
JohnW



Posts: 2207
Joined: Aug. 2006

(Permalink) Posted: Mar. 19 2010,17:14   

Quote (FrankH @ Mar. 19 2010,15:03)
As I can't yet start a new thread and I can't find one that seems to address this issue, one of the "best evidences" he ahas against evolution is that Humans are unique.  One of the traits is our curiosity.  Our curiosity, it was stated, goes against evolution as fear means we should be afraid of everything.

What I replied as a rebuttal is that not everything can be seen as a danger in the beginning.  It is the perceived threat vs the chance to gain food, shelter, etc that need to be weighed against the other, especially for a species that has replaced a great deal of instinct with intelligence.

I think that sort of backfired as he then stated that the loss of instinct in humans shows we were designed as well.

Any ideas?

I think you handled it quite well.  My gut response to nonsense like this is usually along the lines of "Bollocks!"

Natural selection would hardly favour an animal which was afraid of everything.  If it's afraid of everything, it hides in its cave and/or runs away whenever anything happens, and starves to death before it mates.  I suppose it might be a psotive trait in something like a sessile marine worm, but I don't see how it could be anything other than certain death for a vertebrate.

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Math is just a language of reality. Its a waste of time to know it.
- Robert Byers

  
Dr.GH



Posts: 1950
Joined: May 2002

(Permalink) Posted: Mar. 19 2010,18:00   

"instinct" is a hardwired behavior. The rules of the behavior can be very simple. Step 1, pick up object, Step 2, carry to a location, Step 3, repeat, Step 4 (triggered by a big pile of objects) pat down the center. This more or less is "building a nest."

Experiments have shown that "instinct" is merely to steps, but the sequence is learned. The most well known example was when Konrad Lorenz raised mouse pups without any exposure to another mouse. They could do each of the instinctual behaviors- but not in the correct order.

The reduction of instinctual behaviors to smaller and smaller units allows greater and greater adaptability, and requires more and more learning. Humans are rather at the extreme end of the distribution, but only that. We know that many other critters are capable of learning, and are in social groups that facilitate teaching.

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"Science is the horse that pulls the cart of philosophy."

L. Susskind, 2004 "SMOLIN VS. SUSSKIND: THE ANTHROPIC PRINCIPLE"

   
Badger3k



Posts: 861
Joined: Mar. 2008

(Permalink) Posted: Mar. 19 2010,20:28   

Quote (Dr.GH @ Mar. 19 2010,18:00)
"instinct" is a hardwired behavior. The rules of the behavior can be very simple. Step 1, pick up object, Step 2, carry to a location, Step 3, repeat, Step 4 (triggered by a big pile of objects) pat down the center. This more or less is "building a nest."

Experiments have shown that "instinct" is merely to steps, but the sequence is learned. The most well known example was when Konrad Lorenz raised mouse pups without any exposure to another mouse. They could do each of the instinctual behaviors- but not in the correct order.

The reduction of instinctual behaviors to smaller and smaller units allows greater and greater adaptability, and requires more and more learning. Humans are rather at the extreme end of the distribution, but only that. We know that many other critters are capable of learning, and are in social groups that facilitate teaching.

We've seen this teaching/learning behavior in the wild - dolphins, chimps, birds...maybe more.  I have one paper where a rodent was taught to get food by using a rake with it's paws.  Totally fantastic stuff, and it makes me wonder really what exactly "intelligence" is - since more and more animals are exhibiting (or we are noticing, rather) more "intelligent" behavior, perhaps it is not what we always thought it was.  The idea of "intelligence" really being the control/overriding of instinct seems more realistic than the more traditional one.  I'll have to look up that Lorenz stuff - I've read a bit but have not really looked at his work in depth.

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"Just think if every species had a different genetic code We would have to eat other humans to survive.." : Joe G

  
Acipenser



Posts: 35
Joined: Jan. 2010

(Permalink) Posted: Mar. 19 2010,21:52   

Quote (Badger3k @ Mar. 19 2010,20:28)
Quote (Dr.GH @ Mar. 19 2010,18:00)
"instinct" is a hardwired behavior. The rules of the behavior can be very simple. Step 1, pick up object, Step 2, carry to a location, Step 3, repeat, Step 4 (triggered by a big pile of objects) pat down the center. This more or less is "building a nest."

Experiments have shown that "instinct" is merely to steps, but the sequence is learned. The most well known example was when Konrad Lorenz raised mouse pups without any exposure to another mouse. They could do each of the instinctual behaviors- but not in the correct order.

The reduction of instinctual behaviors to smaller and smaller units allows greater and greater adaptability, and requires more and more learning. Humans are rather at the extreme end of the distribution, but only that. We know that many other critters are capable of learning, and are in social groups that facilitate teaching.

We've seen this teaching/learning behavior in the wild - dolphins, chimps, birds...maybe more.  I have one paper where a rodent was taught to get food by using a rake with it's paws.  Totally fantastic stuff, and it makes me wonder really what exactly "intelligence" is - since more and more animals are exhibiting (or we are noticing, rather) more "intelligent" behavior, perhaps it is not what we always thought it was.  The idea of "intelligence" really being the control/overriding of instinct seems more realistic than the more traditional one.  I'll have to look up that Lorenz stuff - I've read a bit but have not really looked at his work in depth.

I like Rico

Quote

Rico's remarkable "vocabulary" raises new questions about language learning in animals

Rico, a dog with an approximately 200-word "vocabulary," can learn the names of unfamiliar toys after just one exposure to the new word-toy combination.


A 9-year-old border collie who apparently understands a vocabulary of 200 words—most of them in German—has led scientists to conclude that the remarkable dog has language-learning ability comparable, in some ways, to a human toddler. Their findings raise anew the question of whether language is strictly a human trait.

Rico is hardly the first non-human animal to show skills at language comprehension; his vocabulary size is comparable to that of language-trained apes, dolphins, sea lions and parrots. But researchers writing in the 11 June 2004 issue of the journal Science say the German canine shows a process of learning called "fast-mapping" not seen to this extent in animals other than humans.

Like a young human child, Rico can quickly form rough hypotheses about the meaning of a new word after a single exposure by inferring that the new word is connected to an object he is seeing for the first time. That suggests to scientists that the ability to understand sounds is not necessarily related to the ability to speak, and that some aspects of speech comprehension evolved earlier than, and independent from, human speech.

Rico's skill was the subject of a news conference in Berlin on 10 June 2004 organized by Science, AAAS and the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Scientist Julia Fischer, along with her Science co-author and Rico's owners, brought the study to life for a room filled with journalists representing media outlets around the world.

And, of course, there was Rico. After an appearance on a German game show about three years ago that launched his science-and-show-biz career, followed by months of methodical scientific testing, Rico emerged from the news conference as an international star.

"Such fast, one-trial learning in dogs is remarkable," said Katrina Kelner, Science's deputy editor for life sciences. "This ability suggests that the brain structures that support this kind of learning are not unique to humans, and may have formed the evolutionary basis of some of the advanced language abilities of humans."

In the early chapters of Rico's story, he appeared on the popular German game show "Wetten, das...?" Fischer heard about his amazing performance and arranged a meeting with Rico in September 2001. After Rico's caretakers agreed to the collaboration, Fischer's team at the Planck Institute set out to test the dog's word skills. In a series of controlled experiments, he correctly retrieved, by name, a total of 37 out of 40 items randomly chosen from his toy collection.

Next, the researchers tested Rico's ability to learn new words through fast-mapping. The German scientists placed a new toy among seven familiar toys. In a separate room, the owner asked Rico to fetch the new item, using a name the Border collie had never heard before.

Rico correctly retrieved the new item in seven of 10 such tests. He apparently uses a process of elimination, much as young children do, to surmise that new words tend to refer to objects that do not already have names. After a month without access to these target toys, Rico retrieved them, upon request, from groups of four familiar and four completely novel toys in three out of six sessions. His retrieval rate is comparable to the performance of three-year-old toddlers, according to the authors.

http://www.aaas.org/news/releases/2004/0610rico.shtml

  
snaxalotl



Posts: 9
Joined: Oct. 2005

(Permalink) Posted: Mar. 21 2010,18:45   

if you haven't seen it, Jon Stewart makes some brilliant observations of the texas school board:
http://www.thedailyshow.com/watch....xtbooks

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Quid quid Latine dictum sit, altum viditur

  
Texas Teach



Posts: 995
Joined: April 2007

(Permalink) Posted: July 18 2011,18:17   

I just got the following via email:
Quote
Dear Science Educator:

Here is the latest information from TEA regarding our Supplemental Science Materials Adoption:

The final recommendations of the Commissioner of Education regarding instructional materials offered for adoption under the Request for Supplemental Science Materials are posted on the TEA website. The document is available at http://www.tea.state.tx.us/index2.aspx?id=2147487077.


The State Board of Education is scheduled to take action regarding the adoption of supplemental science materials at its meeting on July 20-22. More information about the State Board of Education meeting is available at http://www.tea.state.tx.us/index3.aspx?id=1156 .


I thought some of you might want to comb through those and/or pass them along to those who need to.

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"Creationists think everything Genesis says is true. I don't even think Phil Collins is a good drummer." --J. Carr

  
fnxtr



Posts: 2094
Joined: June 2006

(Permalink) Posted: July 18 2011,22:01   

Quote (Texas Teach @ July 18 2011,16:17)
I just got the following via email:
 
Quote
Dear Science Educator:

Here is the latest information from TEA regarding our Supplemental Science Materials Adoption:

The final recommendations of the Commissioner of Education regarding instructional materials offered for adoption under the Request for Supplemental Science Materials are posted on the TEA website. The document is available at http://www.tea.state.tx.us/index2.aspx?id=2147487077.


The State Board of Education is scheduled to take action regarding the adoption of supplemental science materials at its meeting on July 20-22. More information about the State Board of Education meeting is available at http://www.tea.state.tx.us/index3.aspx?id=1156 .


I thought some of you might want to comb through those and/or pass them along to those who need to.

I just get the "agency news" page with no mention of said materials. Site search on "supplemental science materials" just returns the "agency news" page

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"But it's disturbing to think someone actually thinks creationism -- having put it's hand on the hot stove every day for the last 400 years -- will get a different result tomorrow." -- midwifetoad

  
fnxtr



Posts: 2094
Joined: June 2006

(Permalink) Posted: July 18 2011,22:10   

...but here's the TEKS for BIO 9/10/11.

The money shot:

"(7)  Science concepts. The student knows evolutionary theory is a scientific explanation for the unity and diversity of life. The student is expected to:

(A)  analyze and evaluate how evidence of common ancestry among groups is provided by the fossil record, biogeography, and homologies, including anatomical, molecular, and developmental;  "

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"But it's disturbing to think someone actually thinks creationism -- having put it's hand on the hot stove every day for the last 400 years -- will get a different result tomorrow." -- midwifetoad

  
Texas Teach



Posts: 995
Joined: April 2007

(Permalink) Posted: July 19 2011,08:48   

Quote (fnxtr @ July 18 2011,22:01)
Quote (Texas Teach @ July 18 2011,16:17)
I just got the following via email:
   
Quote
Dear Science Educator:

Here is the latest information from TEA regarding our Supplemental Science Materials Adoption:

The final recommendations of the Commissioner of Education regarding instructional materials offered for adoption under the Request for Supplemental Science Materials are posted on the TEA website. The document is available at http://www.tea.state.tx.us/index2.aspx?id=2147487077.


The State Board of Education is scheduled to take action regarding the adoption of supplemental science materials at its meeting on July 20-22. More information about the State Board of Education meeting is available at http://www.tea.state.tx.us/index3.aspx?id=1156 .


I thought some of you might want to comb through those and/or pass them along to those who need to.

I just get the "agency news" page with no mention of said materials. Site search on "supplemental science materials" just returns the "agency news" page

Weird.  Let me try that again:

here

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"Creationists think everything Genesis says is true. I don't even think Phil Collins is a good drummer." --J. Carr

  
fnxtr



Posts: 2094
Joined: June 2006

(Permalink) Posted: July 19 2011,10:11   

That worked. "Discovery Education" gave me tachycardia, until I realized it links to Discovery Channel. Whew!


eta the 'y' in the 2nd 'discovery'.

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"But it's disturbing to think someone actually thinks creationism -- having put it's hand on the hot stove every day for the last 400 years -- will get a different result tomorrow." -- midwifetoad

  
Richardthughes



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Joined: Jan. 2006

(Permalink) Posted: July 19 2011,10:46   

http://scienceblogs.com/dispatc....ion.php

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"Richardthughes, you magnificent bastard, I stand in awe of you..." : Arden Chatfield
"You magnificent bastard! " : Louis
"ATBC poster child", "I have to agree with Rich.." : DaveTard
"I bow to your superior skills" : deadman_932
"...it was Richardthughes making me lie in bed.." : Kristine

  
Henry J



Posts: 4014
Joined: Mar. 2005

(Permalink) Posted: July 19 2011,13:49   

Quote
(A)  analyze and evaluate how evidence of common ancestry among groups is provided by the fossil record, biogeography, and homologies, including anatomical, molecular, and developmental;  "

In detail, or just an overview? Brief overview I could do; details would require studying.

  
fnxtr



Posts: 2094
Joined: June 2006

(Permalink) Posted: July 19 2011,14:03   

Quote (Henry J @ July 19 2011,11:49)
Quote
(A)  analyze and evaluate how evidence of common ancestry among groups is provided by the fossil record, biogeography, and homologies, including anatomical, molecular, and developmental;  "

In detail, or just an overview? Brief overview I could do; details would require studying.

Like a 16-year-old would have the skill set for this.

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"But it's disturbing to think someone actually thinks creationism -- having put it's hand on the hot stove every day for the last 400 years -- will get a different result tomorrow." -- midwifetoad

  
Texas Teach



Posts: 995
Joined: April 2007

(Permalink) Posted: July 19 2011,15:13   

Quote (fnxtr @ July 19 2011,14:03)
 
Quote (Henry J @ July 19 2011,11:49)
 
Quote
(A)  analyze and evaluate how evidence of common ancestry among groups is provided by the fossil record, biogeography, and homologies, including anatomical, molecular, and developmental;  "

In detail, or just an overview? Brief overview I could do; details would require studying.

Like a 16-year-old would have the skill set for this.

Actually, I'm not sure there's anything wrong with that part of the standard as written.  The analyze and evaluate are standard "Bloom's taxonomy" jargon that are overused, but not intrinsically bad.  It's really asking that the kids can pull together the various types of evidence for common descent and explain why it makes a good case.  Listing the types of evidence is a way to force the teachers to cover all of the items (thus the "including" (which we've been told means must) rather than the phrase "such as" (which means may)).  

The problem with the standard is that there will be some teachers who still won't follow it or who give it a day or two at best.  Also, the old TAKS standardized test would rarely have more than one question on evolution, and they tended to be things you could answer without much background.  So there was no real "penalty" for teachers that taught no evolution or even anti-evolution because their students still got decent scores.  

This year we move to the end of course exams in biology and the hope/fear is that they will be much more rigorous.  We teachers haven't had much information yet about what it will look like.  I can say that my physics students who took a field test of the physics EOC told me it covered everything we'd done last year plus some things we hadn't.  The physics test also will have a 3 page formula chart as compared to 3/4 of a page for all three sciences on the old TAKS exam.  If the questions on the biology test actually test some real understanding of evolutionary theory, it will be very interesting to see what happens in schools that haven't been teaching it.

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"Creationists think everything Genesis says is true. I don't even think Phil Collins is a good drummer." --J. Carr

  
Wesley R. Elsberry



Posts: 4465
Joined: May 2002

(Permalink) Posted: Sep. 02 2011,07:58   

Revising Assessment of Clayton Williams, Jr.

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"You can't teach an old dogma new tricks." - Dorothy Parker

    
J-Dog



Posts: 4360
Joined: Dec. 2006

(Permalink) Posted: Sep. 02 2011,08:02   

Quote (Wesley R. Elsberry @ Sep. 02 2011,07:58)
Revising Assessment of Clayton Williams, Jr.

Thanks Wes.  We don't hear nearly enough about non-crazy Texans.  It's good to be reminded that they aren't all like Perry or The Bad Dentist!

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Come on Tough Guy, do the little dance of ID impotence you do so well. - Louis to Joe G 2/10

Gullibility is not a virtue - Quidam on Dembski's belief in the Bible Code Faith Healers & ID 7/08

UD is an Unnatural Douchemagnet. - richardthughes 7/11

  
OgreMkV



Posts: 3268
Joined: Oct. 2009

(Permalink) Posted: Sep. 02 2011,08:07   

OK is the state to watch out for now.  There is an openly creationist head of the education department and she's cleaning house, forcing the people who support science and education out and replacing them with her chosen cronies.

I wish I could tell you more about the EOC Texas project, but I avoid that as much as possible.

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Ignored by those who can't provide evidence for their claims.

http://skepticink.com/smilodo....retreat

   
Robin



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Joined: Sep. 2009

(Permalink) Posted: Nov. 22 2013,07:38   

Not sure where to put this, but this thread seems an appropriate place.

Ahem...a kerfluffle over textbooks that cover evolution.

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we IDists rule in design for the flagellum and cilium largely because they do look designed.  Bilbo

The only reason you reject Thor is because, like a cushion, you bear the imprint of the biggest arse that sat on you. Louis

  
OgreMkV



Posts: 3268
Joined: Oct. 2009

(Permalink) Posted: Nov. 22 2013,07:53   

Quote (Robin @ Nov. 22 2013,07:38)
Not sure where to put this, but this thread seems an appropriate place.

Ahem...a kerfluffle over textbooks that cover evolution.

I think that this isn't so much about the textbook.  Pearson does the Texas state assessments.  The school board may very well be holding the Pearson textbook hostage to get some concessions in the assessment area.

I wouldn't hold anything past these clowns.

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Ignored by those who can't provide evidence for their claims.

http://skepticink.com/smilodo....retreat

   
Robin



Posts: 1430
Joined: Sep. 2009

(Permalink) Posted: Nov. 22 2013,08:02   

Quote (OgreMkV @ Nov. 22 2013,07:53)
Quote (Robin @ Nov. 22 2013,07:38)
Not sure where to put this, but this thread seems an appropriate place.

Ahem...a kerfluffle over textbooks that cover evolution.

I think that this isn't so much about the textbook.  Pearson does the Texas state assessments.  The school board may very well be holding the Pearson textbook hostage to get some concessions in the assessment area.

I wouldn't hold anything past these clowns.

Ahh...ok. I admit that I've read only a little on this and thus I'm not totally acquainted with the issues. I took that last paragraph to indicate that there was discussion and a vote on how long it took for the planet to cool as covered in the textbook, but maybe I missed something. In any event, clearly there's some dubious decision-making going on.

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we IDists rule in design for the flagellum and cilium largely because they do look designed.  Bilbo

The only reason you reject Thor is because, like a cushion, you bear the imprint of the biggest arse that sat on you. Louis

  
OgreMkV



Posts: 3268
Joined: Oct. 2009

(Permalink) Posted: Nov. 22 2013,09:45   

Quote (Robin @ Nov. 22 2013,08:02)
Quote (OgreMkV @ Nov. 22 2013,07:53)
Quote (Robin @ Nov. 22 2013,07:38)
Not sure where to put this, but this thread seems an appropriate place.

Ahem...a kerfluffle over textbooks that cover evolution.

I think that this isn't so much about the textbook.  Pearson does the Texas state assessments.  The school board may very well be holding the Pearson textbook hostage to get some concessions in the assessment area.

I wouldn't hold anything past these clowns.

Ahh...ok. I admit that I've read only a little on this and thus I'm not totally acquainted with the issues. I took that last paragraph to indicate that there was discussion and a vote on how long it took for the planet to cool as covered in the textbook, but maybe I missed something. In any event, clearly there's some dubious decision-making going on.

Yeah, I haven't totally kept up either... but I'm not sure why a Biology book would have a discussion on the cooling of the Earth.

I check the ToC online and saw nothing about the Age of the Earth... I'll check my copy when I get home, but it is a previous edition (not the most current).

All these "midnight" meetings are more suspicious than anything else.

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Ignored by those who can't provide evidence for their claims.

http://skepticink.com/smilodo....retreat

   
Quack



Posts: 1748
Joined: May 2007

(Permalink) Posted: Nov. 22 2013,10:04   

WRT instincts. Some of our instincts are shared with all ilfe on this planet, but if we limit the scope to, sya. mammals, they are obious:

The primary and foremost instinct is the instinc to preserve one's life. if your life is threatened, all your resources are aimed at saving your life. Rational thinking can to a certain degree override that, to sacrifice your life in order to save somebody else. But then we are dealing with another strong instinct, that of preserving you own species.

And sex is of course another aspect of the same. It is both about preserving one's own genes and the species as well.

I don't know what creationists think but thinking is not one of their strengths. That, and excessive amounts of ignorance.

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YEC creationists denigrate science without an inkling of what their lives would be without it. YEC creationism is an enrageous, abominable insult to the the human intellect.
                                                         Me.

  
Cubist



Posts: 346
Joined: Oct. 2007

(Permalink) Posted: Nov. 22 2013,16:54   

Why would the Texas school board worry about whether or not a biology textbook is properly handling a geology thing like the cooling of the Earth? My guess would be, it's about Lord Kelvin's calculations re: the upper limit for the age of the Earth. The board's contingent of YECs could be trying to introduce a YEC lie about Kelvin's calculations, which (according to the finest scholars in YEC-land) proved the Earth couldn't be more than a few thousand years old.

  
Henry J



Posts: 4014
Joined: Mar. 2005

(Permalink) Posted: Nov. 22 2013,21:59   

And here I thought Kelvin's calculations allowed for it to be a few million years!

Or was it several million?

Ah well, physicists found a Curie for that problem.

Henry

  
Cubist



Posts: 346
Joined: Oct. 2007

(Permalink) Posted: Nov. 23 2013,02:27   

Quote (Henry J @ Nov. 22 2013,21:59)
And here I thought Kelvin's calculations allowed for it to be a few million years!

Or was it several million?

Ah well, physicists found a Curie for that problem.

Henry

You got it—Kelvin's initial calculations (as opposed to… whatever bullshit the YECs are making noise about) said the Earth was somewhere between 20 million years old, and 400 million years old. Later, Kelvin revised his estimate to 20-40 million years, still orders of magnitude greater than what YECs want, not that that sort of discrepancy would ever get in the way of a YEC's decision to bear false witness about a scientific finding.

  
jeffox



Posts: 528
Joined: Oct. 2007

(Permalink) Posted: Nov. 23 2013,11:55   

U/Pb radioactive dating of detrital zircons contained in carbonaceous chondrite meteors is the current yardstick, or at least that's what I was taught . . . .
Oh, and quite consistent at just a bit over 4.1 BY.
Anyways, my 2c.

  
Dr.GH



Posts: 1950
Joined: May 2002

(Permalink) Posted: Nov. 23 2013,15:03   

Some of my notes for an article I am working on Re: creationists, abiogenesis, and the age of the earth.

Zircon Geochronology

Zircons form in magma chambers under intense pressures. They are common, and extremely stable making them very attractive for geological dating. Their internal chemistry, and weathering are records of Earth's earliest physical conditions following consolidation and cooling.

Bizzarro, Martin, Connelly, James N., Thrane, Kristine, Borg, Lars E., 2012 "Excess hafnium-176 in meteorites and the early Earth zircon record" Geochemistry, Geophysics, Geosystems Vol 13: 3, 1525-2027

Analysis of the SAH99555 angrite meteorite showed an isotopic enrichment of hafnium-176 from a high energy event ~4869 ± 34 Myr , ~300 million years before the aggregation of solids in the proto-solar system. This reflects an pre-collapse high energy event probably related to the trigger of proto-solar collapse. Terrestrial zircons from the early Archean (Hadean)  approximately 4.3 Ga indicate persistent unhomogenized hafnium reservoirs which limits Earth crustal dynamics to after ~4.4 Ga.

Wilde S.A., Valley J.W., Peck W.H. and Graham C.M. (2001). "Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago" Nature 409 (6817): 175–8.

4.4 Ga- oldest terrestrial minerals dated, Jack Hills Australia.

Mojzsis, S.J., Harrison, T.M., Pidgeon, R.T. (2001). "Oxygen-isotope evidence from ancient zircons for liquid water at the Earth's surface 4300 Myr ago". Nature 409 (6817): 178–181.

Ushikubo, T., Kita, N.T., Cavosie, A.J., Wilde, S.A. Rudnick, R.L. and Valley, J.W. (2008). "Lithium in Jack Hills zircons: Evidence for extensive weathering of Earth's earliest crust". Earth and Planetary Science Letters 272 (3–4): 666–676.

Joe Hiess, Daniel J. Condon, Noah McLean, Stephen R. Noble
2012 "238U/235U Systematics in Terrestrial Uranium-Bearing Minerals" Science 30 March 2012: Vol. 335 no. 6076 pp. 1610-1614 DOI: 10.1126/science.1215507

A mean 238U/235U value of 137.818 ± 0.045 (2?) (compared to the earlier value of 137.88) in zircon samples reflects the average uranium isotopic composition and variability of terrestrial zircon. This distribution is broadly representative of the average crustal and “bulk Earth” 238U/235U composition.

Birger Rasmussen, Ian R. Fletcher, Janet R. Muhling, Courtney J. Gregory and Simon A. Wilde
2011 "Metamorphic replacement of mineral inclusions in detrital zircon from Jack Hills, Australia: Implications for the Hadean Earth" Geology, v. 39, p. 1143-1146

Later inclusions can alter the results of zircon chronologies. Note they would appear younger than they really are.

Dating the Earth/Moon system from the Moon

Another approach was to use lunar rocks recovered by the Apollo missions. These were thought to date to the Earth/Moon formation, and would not have been subjected to the same weathering as terrestrial rock.


Alberto E. Saal, Erik H. Hauri, James A. Van Orman, and Malcolm J. Rutherford
2013 "Hydrogen Isotopes in Lunar Volcanic Glasses and Melt Inclusions Reveal a Carbonaceous Chondrite Heritage" Science 14 June 2013: 340 (6138), 1317-1320


Tacked on the end:

The author of this news item either failed to read the original article, or failed to understand it. The issue is not whether the early Earth had liquid oceans, and at least some dry land in the Hadean, or early Archean. This has been established by stronger data than is used in Marty et al, "Nitrogen Isotopic Composition and Density of the Archean Atmosphere" (see 1-3 below). Nor did the Marty et al paper address the relevant time period for the origin of life. They analyzed fluid inclusions from quartz dated 3.0, and 3.5 billion years ago. We have strong evidence for life as early as 3.8 billion years ago (Ga), and confirmed fossil evidence as early as 3.5 Ga (see 4-6).

The result of this news item is to mislead people less familiar with origin of life research.

1) Wilde S.A., Valley J.W., Peck
W.H. and Graham C.M. (2001). "Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago" Nature 409 (6817): 175–8.

2) Mojzsis, S.J., Harrison, T.M., Pidgeon, R.T. (2001). "Oxygen-isotope evidence from ancient zircons for liquid water at the Earth's surface 4300 Myr ago". Nature 409 (6817): 178–181.

3) Ushikubo, T., Kita, N.T., Cavosie, A.J., Wilde, S.A. Rudnick, R.L. and Valley, J.W. (2008). "Lithium n Jack Hills zircons: Evidence for extensive weathering of Earth's earliest crust". Earth and Planetary Science Letters 272 (3–4): 666–676.

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"Science is the horse that pulls the cart of philosophy."

L. Susskind, 2004 "SMOLIN VS. SUSSKIND: THE ANTHROPIC PRINCIPLE"

   
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