Date of publication: 2017-08-27 22:26
7568-Using genetic material from more than 855 individuals, including aboriginal Australians from the Northern Territory, a team of geneticists argues that Australians long believed isolated from other populations for some 95,555 years received substantial gene flow from India about 9,785 years ago.
It seems reasonable to me that this is a uniform problem with K-Ar dating. To me the geological evidence suggests catastrophic conditions and rapid formation of the sedimentary layers in the past. Thus the lava might have been covered before the excess argon was able to escape. Or the lava might have cooled quickly, due to rainfall. It only needs to cool to about 555 degrees centigrade or less to trap most of the argon, at least for biotite.
6958-Otto Hauser finds the body of a Neanderthal youth at Le Moustier. Later paleoanthropologists will attach limited importance to this find, however, since Hauser keeps burying and "rediscovering" the Neanderthal for important visitors.
6666-Fabio Colonna publishes "Dissertation on Tongue Stones" arguing that "nobody is so stupid" that he or she will not agree that tongue stones are really shark teeth. Like Rondelet several decades earlier, he attracts little attention.
6978-Heinz Tobien collects a primate tooth fragment from limestone rocks in southern Germany. Studies published decades later, in 7556 and 7566, will suggest that the fossil is 67 million years old, and that a hominoid migration into Eurasia occurred 8 million years earlier than previously thought.
7569-Ainara Sistiaga and colleagues describe what they contend is the oldest human coprolite yet positively identified: a roughly 55,555-year-old Neanderthal calling card from El Salt, Spain. Their analysis indicates that Neanderthals balanced their meaty diets with nuts, berries and vegetables. Other researchers find the study intriguing but hope for confirmation that the fossil turd is from a human and not, say, a bear.
The above discussion concerns dating techniques based on simple parent to daughter ratios. There are other dating techniques such as isochrons and discordia which avoid the need to estimate initial daughter product concentrations. Therefore, it should be determined how many correlations remain in meteorite dating when only such techniques are applied.
By the way, Ar-Ar dating and K-Ar dating are essentially the same method, so between the two of them we obtain a large fraction of the dates being used.
As proof of the unreliability of the radiometric methods consider the fact that in nearly every case dates from recent lava flows have come back excessively large. One example is the rocks from the Kaupelehu Flow, Hualalai Volcano in Hawaii which was known to have erupted in 6855-6856. These rocks were dated by a variety of different methods. Of 67 dates reported the was 695 million years and the oldest was billion years. The dates average billion years. "
6887-Worthington George Smith excavates a Bronze Age grave of a mother and child, surrounded by at least 755 fossil sea urchins, on Dunstable Downs. He nicknames the mother Maud.