1 gen 11000 anni a. C. - Jungsteinzeit Neolithikum in Mesopotamien durch Landwirtschaft 11 kBC Davor: - Bootlenecks prior to 50k BC Possibly Toba Volcano Sumatra - Aborriginies 50 kBC, from SE-Asia and later India - 29kBC Venus (Brno), aus Keramik) - Native americans arrived in USA 25k BC - 15 kBC via Bering Street - South America 14000 BC

Descrizione:

-12 800 y ago:
Hiawatha Krater tied to Younger Dryas impact hypothesis, possibly by Cape York Meteorite?

-15 000 y ago:
clovis culture, thought to be the first

-24 000 y ago:
Humans cross Behring street and stay for several thousand years in Beringia (Beringian Standstill)

- 50kY ago:
Mensch wandert

- 70kY ago: Toba

- 200kY ago: Mensch entsteht und wandert aus Afrika, oder ensteht währenddessen

- 600k Y: Neanderthaler+Denisovan LGV spalten sich vom LGV h sapiens ab und wandern


_________________________________________________
-70kY ago:
The Youngest Toba eruption has been linked to a genetic bottleneck in human evolution about 70,000 years ago,[28][29] which may have resulted from a severe reduction in the size of the total human population due to the effects of the eruption on the global climate. According to the genetic bottleneck theory, between 50,000 and 100,000 years ago, human populations sharply decreased to 3,000–10,000 surviving individuals.[31][32] It is supported by some genetic evidence.

Proponents of the genetic bottleneck theory (including Robock) suggest that the Youngest Toba eruption resulted in a global ecological disaster, including destruction of vegetation along with severe drought in the tropical rainforest belt and in monsoonal regions. For example, a 10-year volcanic winter triggered by the eruption could have largely destroyed the food sources of humans and caused a severe reduction in population sizes.[35] These environmental changes may have generated population bottlenecks in many species, including hominids;[36] this in turn may have accelerated differentiation from within the smaller human population. Therefore, the genetic differences among modern humans may reflect changes within the last 70,000 years, rather than gradual differentiation over hundreds of thousands of years.[37]

Other research has cast doubt on a link between the Lake Toba Caldera and a genetic bottleneck. For example, ancient stone tools in southern India were found above and below a thick layer of ash from the Youngest Toba eruption and were very similar across these layers, suggesting that the dust clouds from the eruption did not wipe out this local population.[38][39][40] Additional archaeological evidence from southern and northern India also suggests a lack of evidence for effects of the eruption on local populations, leading the authors of the study to conclude, "many forms of life survived the supereruption, contrary to other research which has suggested significant animal extinctions and genetic bottlenecks".[41] However, evidence from pollen analysis has suggested prolonged deforestation in South Asia, and some researchers have suggested that the Toba eruption may have forced humans to adopt new adaptive strategies, which may have permitted them to replace Neanderthals and "other archaic human species".[42][43]

Additional caveats include difficulties in estimating the global and regional climatic impacts of the eruption and lack of conclusive evidence for the eruption preceding the bottleneck.[44] Furthermore, genetic analysis of Alu sequences across the entire human genome has shown that the effective human population size was less than 26,000 at 1.2 million years ago; possible explanations for the low population size of human ancestors may include repeated population bottlenecks or periodic replacement events from competing Homo subspecies.[45]

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