Graeme, I notice your last couple "studies" have completely ignored energy, placing instead all of our modern virtues on smarts "we're smart and peacful" "we're smart and wealthy" ...
Where's the story about "we're peaceful, wealthy
and smart because we're warmed and clothed and fed by 100 energy slaves each."

$this->bbcode_second_pass_quote('', 'A')fter coal and then the discovery of oil in the 1850s, Homo sapiens exploded to an astounding population of 7 billion in just 170 years. And non-renewable energy slaves paved the way. Oil, in other words, was a powerful Viagra for the species (with unwieldy erections and other side-effects).
Oil also broke all previous energy thresholds. While human population grew 5.4 times since 1850, per capita energy consumption exploded at a rate of 8.5 times. In fact total energy consumption jumped 45 times.
These extraordinary changes gave peasants vicarious lifestyles once only enjoyed by minor kings and queens.
In 1850, the average Tom, Dick or Harry claimed but 2.2 fossil fuels slaves thanks primarily to machines powered by coal, says Hughes. But by 2009, each member of the average human family crowded their household with 93.8 slaves thanks to the combined work of oil, gas and coal. (Add wood, hydro and nuclear energy and another 17.6 diligent slaves must fit in the door.)