CODEX Entry 1210: Dating the origins of man
With every passing month, as new skeletal sites are tested, the story of our origins evolves. In the current view of human evolution, Homo Erectus first evolved 2 million years ago. Then, 600,000 years ago, it gave rise to a Homo Heidelbergensis who left Africa 200,000 years later. One group ventured into the Middle East and Europe, where it evolved into Neanderthals; the other went east, where members became Denisovans, first discovered in Siberia in 2010. The remaining population in Africa eventually evolved into Homo Sapiens, 200,000 years ago. Then these early humans expanded their range to Eurasia 60,000 years ago, where they replaced local hominins without interbreeding.
A brief summary of some of the most important digs in anthropological history highlights the serious problems with this dating model, and the very real risk that the scale and sequence of events are little more than a fiction.
The famous sites of Klasies River Mouth Cave (1967) and Border Cave (1941) contain human remains that were dated through associated material (rocks next to the fossils) to between 65,000 and 110,000 years. The fossils themselves were not analyzed. In 2003 concerns were raised that the samples used to constrain the younger age limit of the Herto fossils originated from a site several hundred kilometers away. Likewise, the older samples were simply buried 1.5m into a sedimentary strata that could have been explained by a burial ritual. Many other bone fragments at the site have been dated at just 1000 years old.
With samples from Florisbad (1932), a failure to analyze the radioactive environment has led to major errors, and at the Tuinplaas dig site (1929), radiocarbon dating of the bones themselves only give an age of 590 years¹. But the same process on the calcareous crust covering the bones yielded 5,600 years². A laser ablation U-series analysis gave an age of 10,000 to 23,000 years³.
The Near East
At Tabun, there has already been long-standing discussions as to why the luminescence and ESR dating sequences do not agree, namely 66,000 and 33,000 years4. But, even using Pa/U analysis, a date of 12,000 is given for the femur bone, but 55,000 years for the mandible. Then using instead Th/U analysis the femur was now aged at 33,000 years and the mandible 62,000 years. At the Skhul cave site associated material was dated in a number of studies. Closed system ESR ages on faunal teeth gave results in the range of about 55,000 to 100,000 years in 19885-6, then 46,000 to 88,000 years in new measurements in 19937, along with associated burnt flint measuring 99,000 to 134,000 years8. In 2005 ESR analysis of a dental fragment from Skhul II, gave a minimum of 131,000 years as its low end, assuming delayed U-uptake, but with open system modeling this would result in virtually infinite age estimates. In contrast the Thermal Ionisation Mass Spectrometry (TIMS) U-series analysis on the dentine from Skhul II yielded only 32,000 years9.
At Vindija, Croatia, in 1998 open system results of spectrometry gave a Neanderthal mandible a mean age of 113,000 years10, yet radiocarbon dating the following year gave 29,000 years11. New ultrafiltration readings, in a 2006 repeat of radiocarbon dating, shifted the dates to 33,000 years12. In 1991 in Spain, the Banyoles Neanderthal mandible was dated at 45,000 years13. In 2006 fragments of one of the teeth were taken for ESR measurement14. The large variations of the 230Th/238U values are astonishing. Hole H1 gives an apparent age of 300 years, while hole H2, less than 0.2 mm away gave a date of 57,000 years!
Mungo 3 offers an important chance to explore multiple tests in different stages of dating technology development. The samples were first collected from associated sediment, radiocarbon dated at 29,000 years (1976)15. Thermoluminescence dating (1996)16 of the same material gave 36,000 to 50,000 years. Optical Luminescence dating of the sediment layer in which the skeleton was buried, with TIMS U-series dating of the calcitic coating and bone shavings, spectrometric analysis on the skull, and ESR dating of tooth enamel (1999)17 concluded that the age of the skeleton was 62,000 years. This led to a violent scholarly debate, with speculations as to why this age estimate was so utterly wrong. Funding was received for yet another dating test (2006)18 that concluded a date of 40,000 years. This date was further complicated as a range of 55,000 to 150,000 years is obtained when the data is corrected for detrital. Data was confused even further when bones in the deeper layers gave younger readings than those buried shallower!
A logical conclusion from all of this is that uranium and its daughter isotopes in bones and teeth are highly mobile. Until a new method of measuring time is discovered, our ability to reconstruct the history of uranium mobilization in the samples is currently completely inadequate, and thus we can not begin measuring these long dates until this is resolved.
For the past 50 years only the mean date has been presented to the bulk of the academic community and, with major discoveries, to the general public. For example a test with a range of 55,000 to 150,000 is presented as 102,500 years, giving a false perception of accuracy. Similarly other dating methods which present other anomalous ranges, are either rejected, or included in calculating the mean. This controversy rages at a very academic level, with the journalists and school children reading their early history completely unaware of the complete chaos behind the numbers presented.
As we can see, anthropogeny relies completely on absolute dating technology. Once absolute systems are secure, referenced dating becomes possible. Yet reference dating, due to its cheapness, has been extremely active for nearly a century, building on the unsound foundations of our absolute dating technologies. The first absolute system out of the blocks was Uranium Lead dating, invented in 1905. It was initially used by geologists to date rocks in consecutive lava beds, and is now rarely used outside its recommended ranges of 1 million to 4.5 Billion years. However, early anthropogenists used this in the pre-war era, the only tool available. The dig for Peking Man in 1923 famously started the race to find the earliest Homominae. The team dated sand in proximity to the skull at 750,000BC. While it was not astounding that the sand was 750,000 years old, the referred age of the skull was dramatic. This inference set in motion a dramatic recalibration of the early existence of Homo Erectus, and echoed around the globe. The Swedish team found the fossilised skull in deeper layers of sand at the bottom of a cave complex. As well as using a blunt dating tool, the researchers made several poor assumptions, namely non-burial and horizontal static sediment layers. The team had run out of funding when they presented the dramatic results to their backers in Europe, securing a further 5 years of grants. Mysteriously this skull and other large bones vanished in 1936, only castes remain.
1945 saw the introduction of radiocarbon dating, initially thought accurate to 70,000 years but later reduced to 30,000, and now back up to 55,000 years. However this technique was not seen as helpful in beating Peking Man, and anthropogenists continued to rely on Ur/Lb until the 1980’s when a second generation of techniques became available, followed by a third in the new millenia.
|Name of Method||Invented||Age range||Material dated||Methodology|
|Radiocarbon||1945||1 – 55,000 years||Organic material such as bones, wood, charcoal, shells||Radioactive decay of 14C in organic matter after removal from biosphere|
|Uranium series||1989||10,000 – 500,000||Uranium-bearing minerals, corals, shells, teeth, CaCO3||Radioactive decay of 234U to 230Th|
|Luminescence (optically or thermally stimulated)||1960||1,000 – 1,000,000||Quartz, feldspar, stone tools, pottery||Burial or heating age based on the accumulation of radiation-induced damage to electron sitting in mineral lattices|
|Electron Spin Resonance (ESR)||1972||60,000 – 2,000,000||Uranium-bearing materials in which uranium has been absorbed||Burial age based on abundance of radiation-induced paramagnetic centers in mineral lattices|
|Cosmogenic Nuclides||2005||1,000 – 5,000,000||Typically quartz or olivine from volcanic or sedimentary rocks||Radioactive decay of cosmic-ray generated nuclides in surficial environments|
|K-Ar dating||1999||100,000 – billion||Potassium-bearing minerals and glasses||Radioactive decay of 40K in rocks and minerals|
|Magnetostratigraphy||1992||20,000 – billion||Sedimentary and volcanic rocks||Measurement of ancient polarity of the earth’s magnetic field|
|Fission track||1988||100,000 – billion||Uranium-bearing minerals and glasses||Measurement of damage tracks in glass and minerals from the radioactive decay of 238U|
|Uranium-Lead||1905||1 million – billion||Uranium-bearing minerals||Radioactive decay of uranium to lead via two separate decay chains|
|Tephrochronology||1990||100 – billions||Volcanic ejecta||Uses chemistry and age of volcanic deposits to establish links stratigraphic successions|
With the Genome Project, anthropogeny began approaching dating from the other side, using the Human Molecular or Evolutionary Clock Model. The Molecular Clock was suggested in 1962 with varying mutation rates between, for example magpies at half the mean rate, and turtles at eight times the mean. Since 1987 a number of scientists, presupposing humans evolved from chimpanzees, have modelled how long it would take for this to occur. Different groups between 1991 and 2012 proposed different lengths, varying from 4 million years to 9.3 million years, with the larger numbers occurring in later studies. 9.3 million years has the unfortunate consequence of stretching early man back into the dinosaur era. Using this DNA scale as an outer band hundreds of teams have begun mapping, then remapping, scenarios that match with sample testing at digs scattered across the world.
The case for the long history of humanity has many challenges. While skeletonization occurs in a couple of years in normal soil, the bones normally leach away in another twenty. In ideal dry conditions bones can last two centuries. Beyond that the only evidence that remains is generated by the process of fossilization. Fossils eventually do not contain the original material. It is effectively a mold of the bone that has been filled with sediment, that is later cemented into rock, making a cast of the original animal. Hence a fossilized tooth eventually contains nothing of the original man’s dentures. This last point is critical. No piece of the original hominid is being dated in long history samples, only sedimentary rock, or more specifically Uranium uptake in the rock. The two main methods for dating bone or teeth today are Uranium series and ESR, both of which give results varying by an order of magnitude depending on the U-uptake curve that the tester inputs into the model. Readings taken in the 1980’s and 1990’s have required significant revision as the understanding of U-uptake from the surrounding environment began to be understood, and localized nonlinear Uranium absorption and seepage became clearer through multiple tests of narrow regions of a single sample.
Further complications arise when dating a fossil based on the sand or soil surrounding it, rather like suggesting a tourist was the same age as the pyramids in which he had a heart attack. It seems reasonable to assume dinosaurs did not bury their dead or die in caves, therefore the fossils lie embedded conveniently in soil strata that settled around them and paleontologists are able to therefore age them reasonably effectively. Humans, buried in sand or soil layers, could firstly have been buried by clan members, but also, many of these burials occurred in collapsed or existing caves. To add to the mix of uncertainty the system assumes evenly spread, unfractionated distribution of Lead, Potassium, trapped Argon, Uranium, or Thorium in the rocks being analyzed. Parent and daughter pairs used in half life analysis, fluctuate much more than previously thought. This is why base material and a detailed radiocarbon map of the fossils’ surroundings are necessary to act as a base line.
Radiocarbon dating has the wonderfully accurate trigger of death, but sadly lacks the stamina to be used on old fossilized bones where carbon content is too low or often contaminated. Radiocarbon dating has been found to be accurate to within 20 years over a 400 year period using tree ring samples, but deviates from other short period measuring systems further out. A study by Chinese and German scientists in the Xingkai Lake catchment found that readings using optically stimulated luminescence (OSL), which measure when sediment stopped receiving sunlight, produced dates of 80,000 years compared to 40,000 years with carbon dating. It is not clear which, or even if both are inaccurate.
Sadly the 20th century experiments in dating human bones and molecular clock hypothesis have now become scientific dogma. It will take generations to replace the story because it is now presented as history, not unlike the creation stories of old. When technology arrives that can accurately date fossilized human bones further back than 55,000 years old there will be a lot of pushback against the new chronology.
¹ Hedges et al., (1996a)
² Vogel and Marais, (1971)
³ Pike et al. (2004)
4 Stringer et al. (1989)
5 Schwarcz et al., (1988)
6 Valladas et al., (1988)
7 McDermott et al. (1993)
8 Mercier et al. (1993)
9 Gru¨net al. (2006).
10 Karavanic et al., (1998)
11 Smith et al., (1999).
12 Higham et al. (2006a)
13 Maroto (1993)
14 Gru¨n et al. (2006).
15 Bowler and Thorne, 1976
16 Chappell et al., 1996
18 Gillespie and Roberts (2000), Gru¨n et al. (2000), and Brown(2000)