Skip to comments.Footprints In The Ash (Human-Mexico-40,000-YA)
Posted on 05/31/2008 12:25:17 PM PDT by blam
Footprints in the ash
By Sid Perkins
May 29th, 2008
Humans may have been walking around what is now central Mexico 40,000 years ago
Footprints (one left) left in volcanic ash that fell in central Mexicos Valsequillo Basin about 40,000 years could be evidence that humans have inhabited the Americas far longer than previously confirmed. Laser scans of the prints (right) confirm their human origins, the researchers report today at the American Geophysical Union meeting.
Footprints left in volcanic ash that fell in central Mexicos Valsequillo Basin about 40,000 years ago are evidence that humans have inhabited the Americas far longer than previously confirmed, a new study suggests.
Analyses of three-dimensional laser scans of the imprints (example at right) confirm their human origin, says Silvia Gonzalez, a geoarchaeologist at Liverpool John Moores University in England.
Previous finds of human remains elsewhere in the region couldnt be precisely dated because they were found in layers of mixed gravels that probably incorporated materials of many different ages.
However, a new analysis of the coarse-grained, print-ridden volcanic ash which would have hardened quickly after it fell, says Gonzalez strongly suggest the material fell around 40,000 years ago, she and her colleagues reported today in Fort Lauderdale, Fla., at a meeting of the American Geophysical Union.
Excavations at several sites have suggested that humans have inhabited the Western Hemisphere for at least 20,000 years, but results suggesting dates of occupation before 14,000 years ago typically havent been confirmed and remain controversial.
Nevertheless, says Gonzalez, recent excavations at a site in Baja California have unearthed a rock shelter containing heaps of shells that have been carbon-dated as 44,000 years old, a finding that bolsters the notion that people lived throughout the region about 40 millennia ago.
(Excerpt) Read more at sciencenews.org ...
From Russia you can see the Diomede Islands. From the Diomede Islands you can see Alaska. Swimming?
By what means are things dated?
Plenty of ways - tree rings, carbon dating, sediments, recorded history.
So we’re still looking at the Bering Crossing, but by canoe instead of walking.
Feasible, but incredibly remarkable for 40,000 years ago. It would have failed far more often than it would have succeeded.
There’s a (off-shore) kelp ‘forest’ running all the way from Japan to the tip of Chile.
Was that the case 40,000 years ago?
This new conclusion puts Clovis Man as an afterthought by tens of thousands of years.
Tree rings go up to 200,000 years?
Carbon dating is as valid as the gore bull warming/climate change models.
sediments are dated ... how?
The recorded history in the Bible is not valid?
Folks whose religious faith informs them that there have been only "10,000 years of existence" will never accept the answer to your question. This is because faith is unquestioning belief and acceptance without proof, whereas science is constant questioning, and a continual search for proof and knowledge. Religion and science are not incompatible except to religions wherein the teachings are rigidly fundamentalist.
A perfect example is found in those religions which teach that their adherents should not obtain medical help for illness or injury, but that one should only pray for whatever outcome God wills. Those religions are certainly entitled to their beliefs, but the rest of us are grateful for modern advances in medical science.
Similarly, religions which hold that the world is about 10,000 years old are perfectly entitled to their beliefs. The rest of us are grateful for scientific advances that enrich our knowledge of the grand sweep of earth and human history stretching billions of years into the past. God gave human beings brains capable of moving humanity from cave-dwellers to spacefarers in only about 100,000 years, and I, for one, think that's one of the most beautiful aspects of His creation.
In Dr. Libbys original work, he noted that the atmosphere did not appear to be in equilibrium. This was a troubling idea for Dr. Libby since he believed the world was billions of years old and enough time had passed to achieve equilibrium. Dr. Libbys calculations showed that if the earth started with no 14C in the atmosphere, it would take up to 30,000 years to build up to a steady state (equilibrium).
If the cosmic radiation has remained at its present intensity for 20,000 or 30,000 years, and if the carbon reservoir has not changed appreciably in this time, then there exists at the present time a complete balance between the rate of disintegration of radiocarbon atoms and the rate of assimilation of new radiocarbon atoms for all material in the life-cycle.
2Dr. Libby chose to ignore this discrepancy (nonequilibrium state), and he attributed it to experimental error. However, the discrepancy has turned out to be very real. The ratio of 14C /12C is not constant.
The Specific Production Rate (SPR) of C-14 is known to be 18.8 atoms per gram of total carbon per minute. The Specific Decay Rate (SDR) is known to be only 16.1 disintegrations per gram per minute.
3 What does this mean? If it takes about 30,000 years to reach equilibrium and 14C is still out of equilibrium, then maybe the earth is not very old.
Sorry, that happens not to be the case.
If you have any legitimate questions on radiocarbon dating I would be happy to address them (but don't even bother with the tripe from the creationist websites -- they lie when it comes to science.)
In the meantime here are some good links on radiocarbon dating:
ReligiousTolerance.org Carbon-14 Dating (C-14): Beliefs of New-Earth Creationists
This site, BiblicalChronologist.org has a series of good articles on radiocarbon dating.
Are tree-ring chronologies reliable? (The Biblical Chronologist, Vol. 5, No. 1)Tree Ring and C14 Dating
How does the radiocarbon dating method work? (The Biblical Chronologist, Vol. 5, No. 1)
Radiocarbon WEB-info Radiocarbon Laboratory, University of Waikato, New Zealand.
There is nothing whatsoever incompatible between ancient peoples migrating across the Bering Strait during the last Ice Age, and migrations in earlier times. Simply because modes of travel would have been primitive does not mean travel was impossible, either on foot or by primitive rafts or boats. It doesn't take much to make a large, if crude raft.
Even today, the Bering Strait is only about 58 miles wide, and the two Diomede Islands are almost exactly in the center of the strait. It's about 27 miles of open water from Siberia to Big Diomede Island, about 2 miles from there to Little Diomede Island, and then about 27 miles to Alaksa.
Homo sapiens has always been a migratory species, despite the rise of the nation-state (Egypt) and the concept of borders about 5000 years ago.
“God gave human beings brains capable of moving humanity from cave-dwellers to spacefarers in only about 100,000”
Actually it is not until Christ that mankind advances - we were still cave dwelling at 0 AD.
“Tree rings go up to 200,000 years?”
No but they are up to 10,000 years and carbon dating is a valid, scientifically proven and reproducible.
Which of the Bible authors was around 10000 years ago.
Well, that was easy.
Really? How is it, then, that the Egyptian, Sumerian and other Mesopotamian, Greek, Hebrew, Chinese, and early Roman civilizations began thousands of years BC, to say nothing of the European peoples who were farming, fishing, creating art, trading, making sophisticated tools, and building great works like Stonehenge, all of which occurred thousands of years BC.
Meanwhile, in the Americas the first evidence for the existence of agricultural practices in South America dates back to circa 6500 BC, when potatoes, chilies and beans began to be cultivated for food in the Amazon Basin. South American cultures began domesticating llamas and alpacas in the highlands of the Andes circa 3500 BC. The Clovis culture in what is now modern New Mexico flourished for some 2500 years, starting at about 3000 BC.
While I totally understand religious faith, I do not understand willful ignorance. Stick strictly to what you surely know as fact. You know ancient Egypt existed, if for no other reason than that it is discussed in the Bible. You know ancient Egypt existed long before Christ. You know ancient Egypt advanced human culture, religious thought (first monotheist religion), building, architecture, irrigation, embalming, and many other achievements. Yet you still claim that human beings did not advance until the Christian era. Willful ignorance. I have no time or patience for it.
Well, that was easy.
If you have any legitimate questions let me know. The stuff you posted above is typical of the fare at creationist sites--a mix of 50 year old quotes and rampant misinterpretations, all combined with a militant ignorance of the field. By this I mean that creationists know that radiocarbon dating is wrong, but they don't know enough about science to make any educated criticisms, nor can they appreciate the rebuttals to their uneducated criticisms. But they just know it's all wrong anyway!
Take a look at the links I posted and if you have any real questions let me know. I do a lot of work with radiocarbon dating and perhaps could give you a better answer than those creationist sites.
What I have a serious problem with is the insistence by some religious fundamentalists (that's what they are) that they not only remain willfully ignorant, but that all the rest of us must as well.
They can believe whatever they danged well want to believe. Just don't push it off onto me or mine through dishonest pseudo-science called intelligent design, or through the public schools, or law, etc.
Folks like knarf are not interested in real answers to real questions. Rather, they want to convert you and I, and all others who do not believe as they do. They want to bring us over to their religious viewpoint.
I'll concede that point, although even a 27 mile journey by raft in open ocean, assuming you could direct it in a straight path, is no small challenge. I would pay money to see anyone attempt it today, using nothing that wasn't available 40,000 years ago.
There has been some reports that mitochondrial evidence (something way beyond my expertise) suggests a south Pacific influx into South America about 15,000 years ago. That seems inherently implausible to me because it suggests an ocean passage far greater than a Bering Sea transit would be, and I don't think ocean currents could explain it.
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