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Recalibrating Carbon 14
Yet perhaps the most significant result of the bristlecone pine tree-ring chronology is its revolutionary implications for the carbon 14 dating method and our understanding of prehistory.
What do bristlecone pines have to do with carbon 14? All living things, including the bristlecone pine, contain a small amount of the radioactive element carbon 14. When an organism dies, the carbon 14 begins to decay at a known rate. By measuring the amount of remaining carbon 14 in a once living organism, scientists can closely estimate when that organism died.
But the radiocarbon dating technique is based on the questionable assumption that the amount of carbon 14 available to be incorporated into living organisms has remained constant for thousands of years. Since carbon 14 concentrations have been measured only in the past four decades, scientists could only assume that the same carbon 14 concentration applied to those past eras where no historical data was available as a check. Indeed, without that assumption, or at least some method of calibration, the radiocarbon dating method would be largely worthless.
Enter bristlecone pine. The 8,200-year sequence of bristlecone rings has provided a remarkable check on the primary assumption of radiocarbon dating. As each ring in a sequence grew, it recorded the carbon 14 concentration in the atmosphere at that time. By measuring the carbon 14 content of various rings, scientists were able to check the accuracy of the radiocarbon dating method. The conclusion of many years of research at the Universities of Arizona, Pennsylvania, and California is that the basic assumption of radiocarbon dating is not grossly in error. Indeed, the bristlecone studies have shown that radiocarbon dating is generally accurate over the past 3,000 years.
Older by 900 Years
But the bristlecone calibration also produced something unexpected: As we go back in time prior to about 1,000 B.C., the amount of carbon 14 in the environment was somewhat greater than at present. This means that certain samples dated by radiocarbon will be dated too young. In other words, the bristlecone pine calibration has shown that some archaeological samples should actually be dated up to 900 years older (earlier) than conventional carbon 14 analysis would indicate!
The bristlecone calibration of radiocarbon has drastically changed the archaeologist's understanding of some early cultures, especially in Europe. A leading British archaeologist, Colin Renfrew, believes the bristlecone pine will revolutionize our chronology of the development of early European civilization. Using the calibrated radiocarbon dates, Renfrew contends that megalithic tombs of Western Europe are actually older than the Egyptian pyramids (which are usually thought to predate the European tombs). He also asserts that Britain's Stonehenge, once thought to have been inspired by Mycenaean (Greek) builders, actually was completed well before the Mycenaean civilization began.”Now it is clear," says Renfrew, "that megalithic chamber tombs were being built in Brittany . . . a millennium before monumental funerary architecture first appears in the eastern Mediterranean and 1500 years before the raising of the pyramids."
Multiple Rings and the Appearance of Age
According to Renfrew, the bristle-cone calibration makes obsolete the formerly accepted theory that prehistoric culture began in the Near East and was only later diffused into "barbaric" Europe.
But could something be wrong with the bristlecone chronology and the resulting calibration of radiocarbon dating? And what of the common belief that God created the earth and all living things about six thousand years ago? How does this square with a reputed 8,200-year tree-ring chronology?
One explanation sometimes offered is that the bristle-cone pines must have produced multiple rings in many years, thus appearing much older (by growth-ring count) than they really are. This explanation might be true for some trees in special environments, but Dr. C. W. Ferguson, the world's leading authority on bristlecone pine dendrochronology, maintains that it is missing rings rather than multiple rings that pose the greatest problem.
"Those who claim we're dealing with multiple rings are sadly misinformed," Ferguson told The Plain Truth.”The real problem is that these bristle-cones grow in an arid environment where they sometimes fail to add a distinguishable annual ring."
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Photos by David Muench
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Moreover, for at least the past three thousand years, the carbon 14 content of the rings is consistent with what would be predicted on the assumption that each bristlecone ring represents one calendar year. Thus it would seem unlikely that the apparent antiquity of the bristle-cones is due to multiple rings.
Another possibility is that God created the trees with the appearance of age. After all, when God created trees, they certainly would have appeared to be at least several years old — and perhaps much older. But would God have created thousands of false rings? "If people are determined to make these bristle-cones younger," observes Dr. Bryant Bannister, director of the Laboratory of Tree-Ring Research, University of Arizona, "I suppose they might as well say God created them with thousands of rings already present. I personally don't believe it, but I guess it's a philosophical position that would be hard to disprove."
Bannister tells of an incident in Lebanon, when he was conducting tree-ring research near a mountain monastery.”One of the monks told me a 6,000-year-old tree had recently been blown down in a windstorm," recalls Bannister.”I was skeptical, but we went over and started to count the rings. It was soon evident that the tree was not nearly that old.
" 'I'm afraid this tree is only about 2,000 years old,' I informed the monk. 'On the contrary,' he replied, 'it may appear by your count to be only 2,000 years old, but you must realize that it was decreed in the beginning that this tree would only add one ring every three years!'
"It was obvious," adds Bannister, "that nothing I could say would ever convince him that the tree was not 6,000 years old."
Of course, Bannister's example is not really the appearance of age so much as the appearance of youth! But the same kind of mentality is involved whenever one claims a tree's true age is other than what the actual number of rings indicates.
A more serious difficulty with the apparent-age theory is that some dead bristle-cone logs have rings that indicate the trees lived and died seven or eight thousand years ago — before the supposed date of creation. If God created the earth only 6,000-years ago, this would imply that He also made "fossil trees" — trees that never actually grew but were only "planted" by God (perhaps to deceive man into thinking the earth was older?).
Whatever the merits of the concept of creation with the appearance of age, most people would agree it should not be pushed to the point where God becomes a cosmic practical joker. God is not the author of confusion (I Cor. 14:33), and His character makes it impossible for him to lie or devise a deceptive creation (Titus 1:2).
Dr. Paul Damon, chief scientist at the University of Arizona Radiocarbon Laboratory, is one of the principal investigators in the bristlecone calibration of carbon 14.”I know people say carbon 14 can't be accurate because it dates creatures long before 6,000 years ago," observes Damon.”But frankly, I think those who invoke `apparent age' so they can keep believing the earth is only 6,000 years old are intellectually dishonest. Paul told Timothy to guard against the pitfalls of 'endless genealogies' and Scripture says a day with the Lord is as a thousand years. I just don't think the Bible should be used to deny what any honest person can plainly see — namely that the earth must be older than 6,000 years."
Indeed, as The Plain Truth has often explained, the Bible allows for a world before Adam and a universe that may be billions of years old. (Write for the free booklet Did God Create a Devil?)
But what of Noah's Flood, which the Bible chronology would date at between two and three thousand years B.C.? Did the bristle-cones survive the Deluge?
The answer is obviously yes. The Flood described in the book of Genesis killed primarily animal life, not plant life. Because of Noah's Flood, "all flesh died that moved upon the earth" (Gen. 7:21). Yet plant life generally survived. For example, Noah sent out a dove which brought back an olive leaf growing on the newly emerged land (Gen. 8:11). Perhaps the bristle-cones were (supernaturally?) preserved in the same fashion.
Beyond 10,000 Years?
According to Bannister, tree-ring chronologies will probably be extended even further — perhaps beyond 10,000 years.”In the next decade or two," Bannister told The Plain Truth," I believe the Europeans may develop a continuous tree-ring chronology even longer than what we've achieved."
But one thing is certain: If the bristlecone pine chronology is indeed accurate, then many traditional and conventional concepts in archaeology and prehistory are destined to be seriously challenged and perhaps revised.
Outliving even the giant sequoias by nearly 2,000 years, the bristle-cone pine is proving to be a treasure trove of intriguing and useful information. Perhaps it is only fitting that the world's oldest living thing should also provide the key to so many fascinating riddles of the past.