DATING TECHNIQUES Relative: Relative stratigraphic position, relative stylistic position, Seriation, Cross dating, with artifacts, fossils, and pollen Chronometric/Absolute: Approx. ranges of reliable dates Potassium/ Argon: (K/Ar) 400,000 to several billion years ago Fission Track Dating: 100,000 to several billion years ago Carbon 14 (conventional): 1500 A.D. to 30,000 years ago Accelerator Mass Spectroscopy (AMS): possibly to 75,000 YA (100, 000 YA not reliable) Thermoluminescence: (TL) present to 10,000, possibly to +200,000 YA Palaeomagnetic/Thermoremnant or Geomagnetic: present to +6 MYA IMPORTANT HOMINID NAMES AND DATES "Black-hole " in the fossil record- between 10 and 5 MYA (or 8 to 4 MYA) from Sivapithecus to Ardipithecus / Australopithecus. "Black-hole" in the fossil record between 3 MYA and 2 MYA ; this is the gap between A. afarensis and Kenyanthropus platyops and Homo habilis Homo ergaster/ erectus Africa and Asia Homo rudolfensis (earliest Homo line?) Koobi Fora, 2 MYA, Baringo 2.4 MYA Homo habilis ( early Homo line) Koobi Fora, Olduvai 2 MYA Homo sp. ? Longgupo, Sichuan, China 1.9 MYA Homo ergaster (later Homo line in Africa only) Koobi Fora, Olduvai, 1.5 MYA Homo erectus (later Homo line throughout Eurasia) Java, Modjokerto 1.9 -1.8 MYA, Sangiran, 1.6 MYA Early archaic Homo sapiens Bodo (Hadar), Ethiopia 600,000 YA Arago (Fance) 400-300,000 YA Bilzingsleben (Germany) H. heidelbergensis 425-200,000 YA, Atapuerca (Spain) H. antecessor (Spain) 320-190,000 YA, Swanscombe (England) 300-250,000 YA Dali (China) 230-180,000 YA Vértesszölös (Hungary) 210-160,000 YA H. s. idaltu (Herto, Ethiopia) 160,000-154,000YA Broken Hill, H. s. rhodesiensis (Africa) 130,000 YA Narmada (India) >100,000 YA Anatomically modern Homo sapiens sapiens - Africa and Near East 100,000 ?115,000 YA (Qafseh, Klasie?s River Mouth, Border Cave ?195.000?) Homo sapiens neanderthalensis Europe and Near East 120,000/70,000 to 35,000 B.P. Out of Africa Theory all Homo originated in Africa, spread throughout the old world, then modern Homo sapiens sapiens originated in a distinct locality in Africa and spread out over the world replacing other existing Hominid populations. Multilinear Evolution with Gene Flow all modern Homo sapiens sapiens evolved out of Homo ergaster/erectus in several interconnected lines when H. erectus migrated throughout the Old World (we do not know where they originated from. These lines were regionally distinct although there has been some gene flow between them. Out of Africa Again and Again with gene flow ? major genetic roots derive from Africa, with early dispersal of human lineage around 1.7 MYA, followed by gene flow between more or less isolated populations throughout the Old World. Later dispersals of populations from Africa between 800,000-600,000 YA, and 290,000-90,000 YA, with gene flow. No evidence for replacement of earlier populations. OTHER METHODS FOR DETERMINING EVOLUTIONARY SEQUENCES Albumin protein "clock" for determining the time when apes split off from Hominids, about 4 to 5 MYA. Vincent Sarich and Allan Wilson Nuclear DNA studies of gorillas, chimpanzees and humans by Charles Sibley and Jon Ahlquist suggest that human and gorilla separation occurred some 10 MYA and humans and chimps some 7 MYA. Mitochondrial DNA clock for defining the origins of fully modern Homo sapiens sapiens traced through the female line. Rebecca Cann, Mark Stoneking and Allan Wilson suggest that the speciation event occurred in Africa around 200,000 years ago (between 140,00 and 290,00) and that this population derived from an ?African Eve? replaced all other Hominid populations. Y chromosome clock ? the male equivalent of the Mitochondrial DNA ? studies are now suggesting that there was an ?African Adam? sometime between 200,000 and 50,000 YA. Both mDNA and Y chromosome studies have been criticized heavily on the rate of mutation and the directionality out of Africa.
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