Children of the Sun



All life requires energy to survive, and our primary source of energy is the sun, a fireball of nuclear fusion.  On Earth, the plant people absorb this energy and convert it into simple carbohydrates.  Humans and other animals extract these nutrients from edible plants, and/or from the flesh of plant eating animals.

Alfred Crosby’s book, Children of the Sun, presents a history of how humans access energy.  It’s a good companion to his earlier book, Throwing Fire, a history of projectile use, spanning from thrown stones to nuclear weapons.  Both discuss the rapid acceleration of innovation, population, and ecological impacts.  This growing instability over the centuries is largely off the radar in our day-to-day lives.  Most of our brain cycles are engaged in the here and now, a pushbutton wonderland of nonstop magic.

Crosby reminds readers of the obvious fact that fossil energy is finite, and the large, high quality deposits are approaching their finish lines.  We are making little effort to wrap our heads around the notion that our high-impact energy-guzzling lifestyle has an expiration date.  Instead, we pretend — with all our might — that the here and now is perfectly “normal,” and everything is excellent.

When the spirits of our wild ancestors observe today’s “normal” they see a nightmarish insane asylum.  Powerful historians like Crosby can vaporize the walls of our madhouse, and allow us to perceive the hundreds of centuries of turbulent cultural evolution that preceded our birth.  We can observe the spirit of progress transition from an occasional draft, to a strong wind, and the full-scale hurricane of today.

In the 200,000 years since the first Homo sapiens punched in at the time clock, almost all generations have been wild nomadic hunter-gatherers, living in a manner that was far simpler, and much closer to sustainable.  For almost the entire human saga, this slower, gentler mode was the long term “normal.”  But it wasn’t normal.

Some scholars have speculated that if space aliens had visited 100,000 years ago, humans would have appeared to be ordinary animals of no significance.  Wrong!  We were roasting steaks with domesticated fire, a spooky trick never performed by ordinary animals.  Fire was domesticated prior to Homo sapiens, maybe 500,000 years ago, maybe a million, nobody knows.

When our ancestors burned biomass like wood, they were utilizing the solar energy stored by the tree.  Fire provided some benefits.  It intimidated hungry predators.  It enabled our ancestors to survive in regions outside the tropics.  It made cooking possible, a huge advance.  Cooking partially predigests foods, making it easier for our guts to extract more nutrients from them.  It also transforms a number of inedible substances into edible sources of nutrition.  Chimps spend six hours a day chewing raw foods.  Of course, progress is never free — fire making eventually led to huge unintended consequences, like megafauna extinctions, industrial civilization, the population explosion, and an unstable climate. 

It’s fun to play “what if…”  What if that first fire starter, who learned how to make sparks with friction, had been ripped to shreds by hyenas prior to his or her discovery?  Without fire, furless hominids could not have survived in chilly non-tropical regions.  The snow monkeys of Japan solved this challenge by evolving heavy winter coats.  Would Homo sapiens have ever evolved at all, limited to a raw food diet?  Would the Americas and Europe of today still be human-free wildernesses, home to healthy populations of mammoths, bison, and sabertooth cats?

Over time, our ancestors got better at hunting and basic survival.  When some groups moved out of the tropics, they encountered conditions for which evolution had not fine-tuned them.  They needed tighter shelters, warm clothing, and food storage for the lean seasons.  Clever innovations could increase the odds for survival, and the cleverer we got, the better.  Over the millennia, our addiction to innovation snowballed.  Like an arms race, the groups possessing the most powerful juju were likely to displace or erase the bubbas with inferior juju.

And so, the clever ones spread around the globe.  Growing numbers eventually ran out of uninhabited lands to colonize, leading to growing friction.  Too much cleverness eventually led to what Ronald Wright called “the perfection of hunting.”  By killing megafauna a bit faster than they could recover over the centuries, big game gradually got scarce.  Our menu shifted toward small game, and then to aquatic edibles.

The domestication of plants and animals was another Earth-shaking innovation.  We could now exploit solar energy more efficiently.  More people could live on less land.  Never before had we controlled so much energy.  Population grew, spurring instability.  The enslavement of animals like horses and oxen provided us with pack animals to carry stuff, and traction animals to pull stuff.  No longer was the work in human communities performed solely by human muscle power.  Enslaved animals could be exploited in many ways.

By A.D. 1000, clever ones had learned how to capture more energy with waterwheels, windmills, and sailing ships, but muscle power was still the primary energy.  We were drifting toward the limits of utilizing solar energy via agriculture and burning wood.  As forests disappeared, the clever ones began burning coal.  Eventually, mineshafts reached the water table, and muscle powered gizmos were unable to remove the water fast enough.  So, brilliant lads invented steam engines that could pump water and keep the mines dry.

Until maybe 1700, human society ran primarily on the muscle power of humans and animals.  The steam engine, like the domestication of plants, animals, and fire, was a major advance with horrendous unintended consequences.  The speed of innovation became a constantly accelerating whirlwind — locomotives, steamships, and multiple-spindle spinning machines.  Lighting switched from the flickering hearth fire, to candles, then whale oil lamps, then coal gas, then kerosene, then electric lights.

Steam engines were pushed to the sidelines by internal combustion engines, which were used to power automobiles, tractors, trucks, locomotives, ships, and many other machines.  Gasoline couldn’t run a sewing machine 100 miles away, but electricity could.  We invented generators, installed power grids, built hydroelectric dams, and nuclear power plants.  We invented telegraphs, telephones, radio, television.  The herd grew explosively from one billion to two, three, four, five, six, seven…  Zoom, zoom, zoom…

For a while, the Peak Oil doomsters made us nervous, with their predictions that the production of conventional oil would likely peak around 2005, which it did.  But we got distracted by the growing production unconventional oil from oil shale (fracking) and tar sands, and returned to pretending that we have no limits.  Let’s go shopping!

Thankfully, Crosby provides readers with an embarrassing birds-and-bees talk about EROEI (Energy Returned on Energy Invested).  In the 1930s, the EROEI of oil production was 100:1 — it took one unit of energy to extract 100 units from the underground reserves.  When he was writing in 2006, it had dropped to 17:1.  Today, it’s less.  Low EROEI means that lots of oil will be left in the ground forever, regardless of how high the price eventually rises.  Imagine having a job that paid $100 per day, but the bridge toll to get there was $105.

Crosby offers us no silver bullet solutions.  “Winning streaks are rarely permanent.”  The easiest approach to our challenges is to continue living foolishly and hope for miracles.  The smartest response would be sanity — limit population, cut consumption, live lightly, and abandon nuclear and fossil energy.  “We have every reason to believe that we are capable of environmental sanity; but first we have to accept that the way we live now is new, abnormal, and unsustainable.”  

It’s a short book, and very easy to read — no charts, graphs, or techno-jargon.  Crosby describes the uncomfortable facts of life in a calm and non-hysterical way.  I have zero complaints about it.  It’s an excellent intro to energy.  He briefly discusses the limitations of alternative energy sources.  The limits are more thoroughly discussed in Renewable Energy Cannot Sustain a Consumer Society.  The huge downside of nuclear energy is better addressed in Too Hot to Touch.  Other energy-related books include Snake Oil: Fracking’s False Promise, Cadillac Desert, The Big Flatline, The End of Growth, Techno-Fix, and Afterburn.

Crosby, Alfred W., Children of the Sun — A History of Humanity’s Unappeasable Appetite for Energy, W. W. Norton & Company, New York, 2006.