Discussion:
The beginnings of agriculture, or "Ice Age Survival – Threading The Genetic and Behavioral Bottleneck"
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Eric Stevens
2016-12-27 01:13:04 UTC
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There is much speculation about the beginnings of agriculture and why
it should have got away independently more or less simultaneously in
several independent parts of the world. Susan Corwin argues that
agriculture got under way only when it became possible and backs up
her thesis with paleo data.

Prior to about 13,000 years ago the climate of the earth was extremely
dusty (think 'dust bowl') indicating that conditions were extremely
unfavourable for plant growth.

" Living in a Dust Storm: the Genetic and Behavioral Bottleneck:
For over 60,000 years, about 3000 generations, far longer than the
time back to the stone age, the struggle to survive was huge.
=> likely, all species of land occupants were “endangered”:
plants, animals, insects, etc."

The primary reason that conditions were so poor was that atmospheric
CO2 was at a level where plants had great difficulty growing.
Agriculture only got underway when atmospheric CO2 rose above 230ppm.
[This probably occurred as temperatures began to rise at the end of
the ice age. EES]

For more information see http://tinyurl.com/j5sxp5l or
https://wattsupwiththat.com/2016/12/26/ice-age-survival-threading-the-genetic-and-behavioral-bottleneck/
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Regards,

Eric Stevens
JTEM
2017-01-20 21:08:49 UTC
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Post by Eric Stevens
The primary reason that conditions were so poor was that atmospheric
CO2 was at a level where plants had great difficulty growing.
Dude, please, I beg you; tell you you're not
really this stupid!

During the glacial period the earth is cooler and
drier. It's drier because -- now get this -- there
is literally OCEANS worth of water locked away in
the glacial ice.

There's just lain LESS moisture.

THAT IS WHY the earth was drier.





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http://jtem.tumblr.com/post/156134395528

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