Talk:Introduction to Paleoanthropology/Hominids MiddlePaleolithic

Homo sapiens migration Out Of Africa
I am a multi-disciplinary scientist and I have spent a lot of studying and thought on these subjects. I have learned one very important thing: keep on multi-disciplinary info and analysis. We cannot talk of migration out of Africa unless we connect them with climate changes, and subsequent changes in the global ocean level. For example it is known that the "moderns" before the Y-chrosomal Adam migrated to Middle East and overlapped with Neanderthals. But due to climate changes the "moderns" have retreated back to Africa several times (around 80-75 ka, when it was a glacial maximum stronger than LGM). Also Neanderthals migrated to Middle East when the climate to the north have been deteriorated. Hence it has been no 30,000 years of overlapping. Also the climate has been deteriorated over the North Africa (Sahara region), and Sahara has been an extraordinary barrier for human migration. Y-chromosamal Adam has been interdisciplinarily defined as from 78,000 years ago. This date and the following 8-10,000 years have been crucial for defining the "moderns". Here many scientists connect the excursions of the geomagnetic field with cosmogenic events, which have attributed high level of galactic (strong) radiation. In the above mentioned case we have a very long geomagnetic excursion (82ka-72ka), being better defined as the Gaotai event, a galactic radiation event (76ka), the Mt. Toba (Sumatra) volcano catastrophic eruption (74-72ka), 1,000 years of volcanic-winter after the eruption, the bottleneck of Equatorial Africa, a very low geomagnetic intensity (66ka-64ka), another cosmogenic event (a supernovae-65ka). All these events combined have generated series of mutations in the newly made Y-chromosamal Adam. Now, the geomagnetic excursions are usually sensed at latitudes higher than 40 degrees north, which is the Europe and most of the North and Middle Asia. The Norwegian-Greenland Sea excursion has been one of rare occurrencies, which generated a semi-global result, affecting East Africa on the trip of the Noth Pole toward the location of the South Pole, affecting Norther Australia on the return trip to the original location, but it has also affected the East Asia. This excursion and the composite of other events have shaped the "moderns". Archeological findings were able to define several settlements of Homo sapiens in South India, which were buried under the ashes produced by the Mt. Toba eruption. These sapiens have not been the "moderns" because the "moderns" have appeared after the Equatorial Bottleneck, hence after the eruption and as a consequence of this eruption. However 80-75ka the level of the global ocean has been very low (associated with a very cold climate), allowing some Homo sapiens to migrate over the Bab el Mandeb Strait (being now the size of a large river) along the southern Asian coast (Yemen-Oman-Souther Iranian coast) to North and South India and probably beyond. However, in the same epoch the Strait of Hurmuz and the entire Gulf have been the Euphrates/Tigris Valley, allowing an easy migration to current land of Iraq, Syria (Mesopotamia), Palestine, Lebanon and and Turky (Anatolia) placed upstream. Probably the Homo sapiens, being found in China (dated at 67ka), have been among those who escaped the consequences of the eruption (being beyond the ashes deposition zone) because they were being located already farther east or northeast (Yunnan and Sechuan). If other Homo sapiens have reached already Eastern Sumatra or Jawa, they have escaped, too (they possibly reached Indonesia, New Guinea and Australia around 65ka-60ka). I have used this example to indicate that a stock of Homo sapiens with no Y-chrosomal mutation in place have possibly reached East Asia, Oceania and Australia before 60ka. Or these people have had the Y-chromosomal mutation (occurred 80-78ka) but they do not hold other new features resulted from the bottleneck and local genetic diversity, which followed in Africa. These people could be seen as "early" Homo sapiens by anthropologists and archeologists. At this place in time they have been genetically inferior to those from Africa, but the distiction has been minimal(the same skeleton but lower cognition). Around 78ka we could have "moderns" with lower cognition in the Middle East, too. Probably they have migrated, after climate changes to warm, toward Iran, Caucasus, and Western Asia. Talking about the geomagnetic excursions a chain of them have occurred at 42ka, 34-32ka, 25-28ka, 20-18ka, 14-11ka, 7-4.5ka, and 2.8ka. I have mentioned them because one of the main mutation for cognition has been recorded around 40-38ka (see Bruce Lahn-Science article-2006). Another neuronal mutation has been recorded 4.8ka during the Solovki excursion (7.0-4.5ka). Most of these excursions have been recorded at global level, influencing the Out Of Africa "moderns". However the excursions have been known for "regional behaviors", which means their effect have been stronger in some geographic location and weaker in others. There is a current among the scientists to find ways to connect the said excursions (associated to cosmogenic events) with the evolution of haplogroups and some distinctive biological features. The migration of people along the pre-history and history is largly seen as the chasing for climate refuges, where the best resources are available. This allows litle place for regional continuity theory. One last idea will be about the powerfull event of the Norwegian-Greenland Sea excursion over the Homo sapiens from East Africa and the Neanderthals from Europe (France). It has generated the first expresion of art in Europe and in the East and South Africa. If some rock-painting from Australia have correct dates (75ka-60ka), then this phenomenon has spread along the excursion path to Australia. In the end it will be hard to estimate the evolution of the Mongoloids in East Asia because they have probably evolved on the exposed continental shelf of the Bohai, Yellow, East China and South China seas, which have turned flooded by current seas in the last 8,000 years. Eventually on actual sea bottoms would be many things to discover and consider for human evolution. Dan M. Mrejeru