Title: Bones, Rocks and Stars – The Science of When Things Happened
Author: Chris Turney
Publisher:Macmillan, 2008 (First published 2006)
ISBN: 978-0-230-55194-7
Pages: 182
When a new archeological find is unearthed, or a paleontologist turns up with a fossil, or a cataclysmic event is said to have occurred in the earth’s early history, the foremost question on our minds is when it has occurred. And science usually comes up with an estimated age of the artifact or event. How do they do it? How can we say with certainty (though many are drastically revised on further evidence or new technology) that an event has occurred this many years ago? Chris Turney’s book is an excellent catalogue of such techniques used by scientists presented with delightfully lucid examples that can be appreciated by any class of readers. In fact, this book may even be recommended as a must-read for any reader of popular science. Turney argues that the past is the key to the future and we must use all the available time to see it with full comprehension. The book also makes scathing criticism about ‘Creation Scientists’ who take the Bible literally and argue that the earth was created only 6000 years ago. Such shortsightedness is perilous for the present society as we are denied the details of past extinctions of life species and to learn the lesson from them, at least to ward off a human-induced catastrophe in future. The most important contribution made by the author is the instructive description of various dating methods such as radiocarbon, argon-argon, electron spin resonance, luminescence and such. The book is superbly structured as to gently move from newer to older events, ending with the dating techniques of the origins of earth and the universe. The author is eminently well suited for the job, as he is a geologist and Chair in Physical Geography at the University of Exeter and has a rich repertoire of practical experience such as dating on the ‘Hobbit’ fossil from Flores, Indonesia. Interested readers may also like to go through Chris Stringer’s The Origin of Our Species, reviewed earlier in this blog, which also dedicates a considerable part to explain dating techniques.
The book begins with a literary exercise of estimating the date on which King Arthur is believed to have lived in England. Even though this does not include any of the phenomenon described by physical sciences, the piecing together of information of historical and literary treatises provides an entertaining idea of the whole operation. At the same time, radiocarbon dating provides a definitive estimate of the antiquity of an organic object. This is best illustrated in the unveiling of the ‘Shroud of Turin’, which was believed to be the burial shroud of Jesus Christ. However, when tested, it turned out that the linen cloth was made in the Middle Ages, precisely at around the period it was discovered by a French knight. But, here lies the crucial point; the radiocarbon dating can at best be represented only as a possible period in which the event had occurred. The three labs, to which a piece of the shroud was entrusted, came out with periods that are slightly offset from the figures declared by others. This fueled another controversy to breakout, which is still not settled. This argument is put succinctly by the head of the team from Oxford University with a fitting reply that if you employ scientific methods, you have to settle for a probability of dates and if you want absolute certainty, you have to rely on faith! But we should not lose sight of a commendable deed among this flurry of opposing voices – the decision of the Vatican – Pope John Paul II was the pontiff – to submit the shroud to scientific examination. The Church could have happily continued the status quo ante, and none would’ve been the wiser. That’s why the world should spare a congratulatory note to the late Pope, who boldly decided to sweep away the cobweb of superstition in order for scientific enlightenment to pass through. The shroud turned out to be forgery and this may perhaps deter later religious heads from testing their own relics!
Another technique which is sure to intrigue the reader is dating used with tree rings. Trees accumulate growth rings on its trunks, whose width is proportional to its growth in that year, which is more in a warm, moist climate. Each year therefore produces a characteristic ring, which will be similar to other trees growing in that area. Gathering and comparing data on rings, the patterns may be stretched back to antiquity by overlapping information from different pieces of wood that share an overlapping period in their growth stages. The significant advantage of this method is that the year of cutting of the tree could be pinpointed. And this data presents a scenario which would send a chill down our spines. Studies show very dry or cold period occurring uniformly around the planet, lasting five to ten years. These events occurred in 2345 BCE, 1628 BCE, 1159 BCE and 536 CE. Such a long drought is sure to unsettle even today’s technological societies. This thing happened in the past and so, it may recur in the future. The reasons for this strange phenomenon must be assertively found in order for us to brace ourselves and prepare for a disaster that may come somewhere in future. Turney identifies the reason as the appearance of comets, which seems to be a farfetched idea. We have seen so many comets in the historical past and they wreak havoc only when physically impacts the earth. If the author is right, they may also cause drought by cooling the planet through reflection of sunlight back into space by the particles of ice and dust which constitute the comet’s tail. But unfortunately, this also is unconvincing. The earth passed through the tail of Haley’s Comet when it visited us in 1910 without any untoward incident. To cap it all, there may be doubts about the veracity of extending the inference from tree rings on a global scale. We know that climatic conditions vary on a span of a few hundred kilometers and the growth patterns also will be different. So, unless a chronology is built up for a specific area, how can the results be extrapolated on a worldwide scale?
The author narrates an interesting anecdote in which the career of a dendrochronologist (one who specializes on tree dating) was cut short by a mistake committed by him. This researcher’s corer got stuck in a very old tree while he was working on a bristle cone pine. Looking like a stunned trunk, the tree was felled by a ranger on his request. But the scientist was amazed to find 4950 rings on the trunk, meaning that the tree was growing for that many years, and that it was in its prime when the Great Pyramid of Khifu was under construction! Turney vouches that this unnamed individual never ever did dendrochronology again. Looks like a wanton misuse of the world’s oldest living organism, just for saving the cost of a common tool, isn’t it? But on second thoughts, is it? The tree provided valuable insights on extending the tree ring chronology for thousands of years in that area, by this accident. We read in Salim Ali’s autobiography, The Fall of a Sparrow (reviewed earlierin this blog) that ornithologists shoot down a bird to learn about it. In that light, would killing a stunted tree count much? There may be counter opinion that the unfortunate guy may be rewarded for extending the frontiers of dendrochronology by a few thousand years.
Turney asserts that a primitive homo species called Home floresiensis lived in the Flores Island of Indonesia till a few centuries ago. He cites radiocarbon dates on some finds in that area and also legends from native people in support of his argument. Many of his peers oppose this postulate on the basis that the Wallace Line separates this island from Asia and hence the creatures must have crossed over the ocean in a canoe or something, which is outside the technical capability of the species, when judged by cranial volume. However, the author’s insistence on the veracity of the find runs counter to the thread of rational discussion carried through out the text. We have to suspect that the motive being the author’s personal participation in the dating of the remains. This could’ve been avoided.
The book begins with a literary exercise of estimating the date on which King Arthur is believed to have lived in England. Even though this does not include any of the phenomenon described by physical sciences, the piecing together of information of historical and literary treatises provides an entertaining idea of the whole operation. At the same time, radiocarbon dating provides a definitive estimate of the antiquity of an organic object. This is best illustrated in the unveiling of the ‘Shroud of Turin’, which was believed to be the burial shroud of Jesus Christ. However, when tested, it turned out that the linen cloth was made in the Middle Ages, precisely at around the period it was discovered by a French knight. But, here lies the crucial point; the radiocarbon dating can at best be represented only as a possible period in which the event had occurred. The three labs, to which a piece of the shroud was entrusted, came out with periods that are slightly offset from the figures declared by others. This fueled another controversy to breakout, which is still not settled. This argument is put succinctly by the head of the team from Oxford University with a fitting reply that if you employ scientific methods, you have to settle for a probability of dates and if you want absolute certainty, you have to rely on faith! But we should not lose sight of a commendable deed among this flurry of opposing voices – the decision of the Vatican – Pope John Paul II was the pontiff – to submit the shroud to scientific examination. The Church could have happily continued the status quo ante, and none would’ve been the wiser. That’s why the world should spare a congratulatory note to the late Pope, who boldly decided to sweep away the cobweb of superstition in order for scientific enlightenment to pass through. The shroud turned out to be forgery and this may perhaps deter later religious heads from testing their own relics!
Another technique which is sure to intrigue the reader is dating used with tree rings. Trees accumulate growth rings on its trunks, whose width is proportional to its growth in that year, which is more in a warm, moist climate. Each year therefore produces a characteristic ring, which will be similar to other trees growing in that area. Gathering and comparing data on rings, the patterns may be stretched back to antiquity by overlapping information from different pieces of wood that share an overlapping period in their growth stages. The significant advantage of this method is that the year of cutting of the tree could be pinpointed. And this data presents a scenario which would send a chill down our spines. Studies show very dry or cold period occurring uniformly around the planet, lasting five to ten years. These events occurred in 2345 BCE, 1628 BCE, 1159 BCE and 536 CE. Such a long drought is sure to unsettle even today’s technological societies. This thing happened in the past and so, it may recur in the future. The reasons for this strange phenomenon must be assertively found in order for us to brace ourselves and prepare for a disaster that may come somewhere in future. Turney identifies the reason as the appearance of comets, which seems to be a farfetched idea. We have seen so many comets in the historical past and they wreak havoc only when physically impacts the earth. If the author is right, they may also cause drought by cooling the planet through reflection of sunlight back into space by the particles of ice and dust which constitute the comet’s tail. But unfortunately, this also is unconvincing. The earth passed through the tail of Haley’s Comet when it visited us in 1910 without any untoward incident. To cap it all, there may be doubts about the veracity of extending the inference from tree rings on a global scale. We know that climatic conditions vary on a span of a few hundred kilometers and the growth patterns also will be different. So, unless a chronology is built up for a specific area, how can the results be extrapolated on a worldwide scale?
The author narrates an interesting anecdote in which the career of a dendrochronologist (one who specializes on tree dating) was cut short by a mistake committed by him. This researcher’s corer got stuck in a very old tree while he was working on a bristle cone pine. Looking like a stunned trunk, the tree was felled by a ranger on his request. But the scientist was amazed to find 4950 rings on the trunk, meaning that the tree was growing for that many years, and that it was in its prime when the Great Pyramid of Khifu was under construction! Turney vouches that this unnamed individual never ever did dendrochronology again. Looks like a wanton misuse of the world’s oldest living organism, just for saving the cost of a common tool, isn’t it? But on second thoughts, is it? The tree provided valuable insights on extending the tree ring chronology for thousands of years in that area, by this accident. We read in Salim Ali’s autobiography, The Fall of a Sparrow (reviewed earlierin this blog) that ornithologists shoot down a bird to learn about it. In that light, would killing a stunted tree count much? There may be counter opinion that the unfortunate guy may be rewarded for extending the frontiers of dendrochronology by a few thousand years.
Turney asserts that a primitive homo species called Home floresiensis lived in the Flores Island of Indonesia till a few centuries ago. He cites radiocarbon dates on some finds in that area and also legends from native people in support of his argument. Many of his peers oppose this postulate on the basis that the Wallace Line separates this island from Asia and hence the creatures must have crossed over the ocean in a canoe or something, which is outside the technical capability of the species, when judged by cranial volume. However, the author’s insistence on the veracity of the find runs counter to the thread of rational discussion carried through out the text. We have to suspect that the motive being the author’s personal participation in the dating of the remains. This could’ve been avoided.
The book is highly recommended.
Rating:4 Star
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