The Seven Daughters of Eve by Bryan Sykes.
Mitochondrial DNA tracing of human kind
Chapter 21 Jasmine. Pg 260 . The youngest of seven clusters of DNA
“The Great Ice Age was at an end. The ice caps and glaciers had been melting for the past four thousand years as global temperatures climbed erratically toward present-day levels. [That would place this story about 8,000 years ago. The water that had been trapped these great reservoirs of ice now flowed into the ocean basins, so that sea levels were rising around the globe. The low-lying plain that lay between Arabia and Iran was flooded as seawater seeped inland past the Straits of Hormuz to create the Persian Gulf. The Adriatic pushed the shoreline further and further north towards its present position n the lagoon of Venice. Seawater rushed through the Bosporus and poured into the Black Sea. Britain and Ireland began to lose their connections to the European mainland and to each other as water flowed into what are now the North Sea, the Irish Sea and the English channel. On the other side of the world Australia and New Guinea, which had been jointed together as Sahulland, were separated as the Torres Straits filled with water. The flat plains of Sundaland that once connected Malaysia, Sumatra, Java and Borneo into a single land mass were now seabed. The crucial land bridge that connected Asia an the Americas finally sank beneath the cold waters of the Bering Straits.
“All these lands were inhabited, and had to be evacuated as the sea level rose. This was not the gradual process once imagined, with imperceptible advances measured in fractions of a millimeter per year. It now appears that the sea rose in a series of rapid stages, by several metres over only a few decades as water was suddenly released from the melting continental ice caps that had become vast freshwater lakes, their outlets to the sea blocked only by frozen tongues of ice. One such tongue lay across the opening of what is now the Hudson Bay, holding back an enormous inland lake that covered most of Canada. When this ice barrier was finally breached and the water gushed out into the ocean, the sea level rose around the world by half a meter overnight. Sea-level rises of this magnitude today would now drown millions of square miles of low-lying land but would inundate many of our coastal and estuarine cities. If this version of events is accurate, then the sudden end of the Ice Age brought tragedy to the inhabitants of the coastal plains. May would have drowned or seen their livelihoods destroyed. Great floor myths permeate many mythologies. Perhaps this is their foundation.”
Earth's Background.
The last Ice Age, the Würm, began 100,000 years ago and ended about 10,000 years ago. During the height of Würm glaciation, ca 24,000–10,000 ybp, most of western and central Europe and Eurasia was open steppe-tundra, while the Alps presented solid glaciers. Scandinavia and much of Britain were under ice. The drop in sea level caused by water locked up in glaciers would allow one to walk on dry land from France to Ireland to Norway to Alaska, albeit on ice and snow, and animals crossed on tundra that would become the Bering Sea to the Americas. Early man's journey out of Africa along the shores of Asia found the Red Sea narrow ; no Persian Gulf was in the way ; India was wider ; Indonesia was part of mainland; China, Korea, and possibly Japan were one; and Australia included New Guinea.
In North America, the Wisconsin glaciation reached its greatest advance 21,000 years ago and ice covered to the Ohio River. An eastern ice sheet covered most of Canada, the Upper Midwest, and New England, while a western sheet spread from Alaska to the Rockies over parts of Montana and Washington;. The Caribbean was more like a a lake. When it ended about 10,000 years ago, it had radically altered the geography of North America north of the Ohio River. I think we can be glad that the world has warmed a bit since then. It also allowed mankind to move throughout the Americas.
What have we to look forward to, by looking back?
The last interglacial, before our current warming period, is called the Riss-Wurm or Sagamon or Eemian in different parts of the world, began about 130,000 years ago and lasted about 20,000 years.
The warmest peak of the Eemian was around 125,000 years ago, when forests reached as far north as North Cape, Norway, well above the Arctic Circle. Oak and other hardwood trees grew as far north as Oulu in Central Finland (65°N). Sea levels at that time were 4-6 meters higher than they are now, indicating greater deglaciation than today (mostly from partial melting of the ice sheets of Greenland and Antarctica). Scandinavia was an island due to the inundation of vast areas of northern Europe and the West Siberian Plain. Central Europe (north of the Alps) is found to be 1–2 °C warmer than present . In North America trees grew as far north as southern Baffin Island in the Canadian Arctic (70°N) instead of only to northern Quebec as today (65°N). Much as the peoples living then in what became Seas had to relocate, so to will people in coast lands today have to move to higher ground. Florida was once much wider and the future may see the land south of Orlando become Gulf.
We are in the warming period right now between Ice Ages . Our current warm period between Ice Ages is called the Holocene and we are about 10,000 years into it – we think of this as normal, having never lived through the extremes that earth provides.
There are cycles within the epoch global cycles of cold and warm. There was a particularly warm period in the middle ages when Greenland was green (Eric the Red). There was a Little Ice Age in which hotels were built on the Baltic Sea to service the coach trade across the ice to Scandinavia. That Little Ice Age is considered to have ended about 1860, just before the American Civil War. We continue now to be in the period of warming from the great Würm Ice Age and also of warming from the Little Ice Age.
Conditions were sometimes localized. A massive study in Denmark showed that Boreal Period about 8,000 BC was still cold but continued warming for two thousand years until the Atlantic Period with a total rise of about 4 degrees and water level rise of 22 meters.. What in 7000BC was a freshwater Lake Ancylus by 6000 BC became the saltwater Baltic Sea . Things remained uniformly warm through the Atlantic period till 4000 BC when a slight cooling trend started that continued until 1200 BC with a sharper dip about 600 BC, warmed a bit from 200 BC to 200 AD, dipped sharply about 500AD then warming again from 750 to 1200 AD followed by a dip about 1500 AD and has been warming since, but now stand about 3 degrees cooler than the Atlantic Period warm.
Human Era.
To put all of this into human perspective, Homo Antecessor, with many subspecies, had been scattered round the earth when the last Ice Age began and died out about this time. Homo Neanderthal hunted in Eurasia and was adapted as a cold tolerant species. Homo Sapiens, a recently developed species in Africa had just a few thousand members and would be classified today as endangered. Forced to relocate by weather changes that also lowered sea levels, a small band of Elder Man, H.S Idaltu (160,000-?), crossed the then narrow Red Sea and the non-existent Persian Gulf about 80,000 years ago to populate southern Asia – India, IndoChina, Australia (Indonesia was part of the Asian mainland) and coastal China. A second wave “out of Africa” about 40,000 years ago spread into rich hunting land in Central Asia. Five thousand years later these Cro-Magnon people moved into Europe and the rest of Asia spreading the Indo-European language.
Increased glaciation forced them into southern Europe- Spain, Italy, Greece and southern Asia – India, IndoChina and onto lands that would swallow up their remains when the seas rose again.
These big boned people were followed by a taller, leaner subspecies newly from Africa
about 10,000 years ago, Homo Sapien Sapien. These people developed agriculture and herding while residing in the fertile Middle East, and the idea spread throughout the world with a genetic mix of 80:20 of older and newer humans now found in Europe. Indigenous peoples of Australia and America are of the older variety. Asia and Africa have pockets of every pure and mixes too complex to decipher.Time Table
100,000 Beginning of Würm Ice. (Last Ice Age, to 12,000)
100,000 Homo Antecessor dies out
80,000 Of a human pop of c 2,000, 150 people crossed “Out of Africa”
60,000 Homo Sapiens from Africa to India.
60,000 Adam in Africa
45,000 Homo Sapiens to Australia.
40,000 Homo Sapiens Cro-Magnon, spread to central Asia.
35,000 Beringia – Asia-N.Am land bridge exchange animals. Horse from America to Asia.
35,000 Cro-Magnon spread into Europe
22-15K Beringia – land bridge of tundra has people
25,000 Homo Neanderthal goes extinct
15,000 Homo Sapiens to Americas (Range 22-10K)
15,000 Wurm Ice Age final chill brings extinction of many large mammals
13,000 Start Little ice age in Europe. Cro-Magnon to southern Eurasia.
12,000 End of Wurm ice age. Man follows the thaw.
10,000 Homo Sapiens Sapien leaves Africa for Middle East Start Mesolithic Period (Hunter-gatherer) Pop 1 million.
9,000 Start of Holoscene Warm Age.
8,500 Agriculture, husbandry, pottery. Start Neolithic Period (modern man mixes with Cro-Magnon while spreading agriculture)
8,000 Cave paintings in Europe. Second wave to American west coast by boat
7,500 Start of Sahara desert, 20-fold increase. Bible Flood
7,000 Proto-Indo-European language develops on Caspian steppe.
6,500 Middle European solar circles (wooden Stonehenges)
6,000 Tamed horse. Proto-Indo-European spreads to India to Iceland
5,500 Hieroglyphs
5,000 Pyramids, Stonehenge. End of Warm Age. Start Copper/Bronze Ages
4,000 Proto-Indo-European replaced by localizations.
3,000 Iron age, Troy. Celtic Europe Abraham, Zoroaster
2,500 Greece, Alexander Buddha, Confucius
2,000 Rome. World Pop. 100 M Jesus
1,500 Byzantine; Rome dies of lead poisoning. Muhammad. Start Dark Age.
1,200 Start of Medieval Warm period, sea levels rise again.
1,100 Charlemagne. Start Middle Ages
1,000 Leif Eriksson,
900 Start Crusades. Battle of Hastings
800 Genghis Khan End of Medieval Warm
700 Start Little Ice Age
650 Plague decimates Europe
600 Fall Constantinople, Columbus . Printing . Start Renaissance.
500 Di Vinci, Luther, Michelangelo, Copernicus . Little Ice Age
400 Shakespeare, Brahe, Galileo, Kepler.
300 Newton
250 Start Industrial Age, Franklin.
232 American Revolution. Watt.
200 Rumford, Napoleon
150 Civil War, Darwin End Little Ice Age
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