Peak Horse



In the early 1900s, automobiles, trucks, buses, and tractors were becoming very trendy.  The human population was two billion and growing, while the horse population peaked and declined.  Model T Fords did not require five acres of good grassland to fuel them, an area that could feed six to eight people.  While grassland was, in theory, a renewable resource, there was not an infinite supply of it.  Pasture could be degraded or destroyed by overgrazing, drought, plowing, or urban sprawl.

Of course, motor vehicles are dependent on a wide variety finite nonrenewable resources.  The global production of conventional oil peaked around 2005, and now we’re briskly advancing toward the peak of unconventional sources — tar sands, shale deposits, and deep-water — the fossil energy that’s far more difficult and expensive to extract.  When we pass Peak Oil, production will begin a continuous decline, and prices will rise.  Some estimate that this will begin around 2030.

Life is solar powered.  Plants have solar panels that use light to create carbohydrates.  Plant eating animals acquire these nutrients by feasting on the greenery.  Meat eating animals consume the flesh of plant eaters.  Legions of wee organisms extract the nutrients from biomass and build topsoil.  Solar energy is also embedded in coal, oil, and natural gas — carbon that was sequestered millions of years ago.

Throughout the three million year era of our ancestors, muscle power was the primary energy for moving people and things.  Muscle power is highly versatile, able to run on a variety of edible fuels — meat, eggs, fruit, nuts, roots, insects.  More versatile than horses, human muscles can move people and stuff through dense rainforests, up rugged mountains, and across deserts.  Horses are poorly adapted for hot climates and arctic regions.

Pita Kelekna noted that humans have a long history of acquiring stored solar energy via the consumption of horse flesh.  At the Roche de Solutré site, near Mâcon, France, archaeologists found a 2.5 acre (1 ha) bone bed, up to 29 feet (9 m) thick, containing the bones of up to 100,000 horses.  Neanderthals hunted horses there 50,000 years ago.  Later, humans hunted them from 37,000 to 10,000 years ago. 

Around 9,000 years ago, the last horse in the Americas died in Patagonia.  The once plentiful wild horses of Western and Central Europe’s river valleys were apparently eliminated by overhunting 8,000 years ago.  To the east, large numbers of horses managed to survive on the wide open Eurasian steppes, where trapping animals was less easy.

Horses were domesticated about 6,000 years ago.  Kelekna described how nomadic pastoralists became skillful horse parasites.  “The Mongols lived off the horse; as they traveled, they milked and slaughtered for food.  They consumed a steady diet of milk and yoghurt, drank the horse’s blood, and mixed dried milk paste with water, dried meat, and millet.”

Eventually, clever folks realized that horses were not just a tasty form of solar energy — they also had more muscle power than humans.  If properly enslaved, they could be used to pull stuff, haul stuff, and carry riders.  Four legged slaves enabled a tremendous expansion of soil mining, forest mining, mineral mining, bloody empire building, and economic growth.  They unlocked the gateway to industrial civilization.

Around 25,000 years ago, the mammoth hunters at the Dolní Věstonice site in the Czech Republic heated their mammoth bone huts by burning the solar energy embedded in two fuels: mammoth bones and black coal.  By the mid-1500s, English forest miners had nearly succeeded in eliminating the ancient rainforest.  This created an energy shortage that inspired a large scale transition to coal burning.  In the late 1800s, the oil industry emerged, and the war on the future became turbocharged.

As the age of mechanical horsepower accelerated, the long era of four legged horse power rode off into the sunset.  My grandparents witnessed the advent of Peak Horse, and my parents saw work horses largely disappear from farms and cities.  Physicist Albert Bartlett calculated that children born after 1966 will see the world consume most of its oil during their lifetime.  Industrial civilization has an expiration date.  So, we’ll just have to go back to horse power, right?  Well, umm, there are some challenges.

Eric Morris wrote a fascinating essay to help us remember life in the Peak Horse era.  By 1898, big city streets were jammed with horses, carriages, and wagons, squishing through a deep layer of manure and urine, past rotting horse carcasses, amidst dense clouds of flies and overpowering stench.  Cities were rapidly growing, as hordes immigrants moved in to enjoy miserable industrial jobs, while living in crowded, filthy, disease ridden slums. 

Each horse emitted 15 to 30 pounds (7 to 14 kg) of manure daily — 3 to 4 million pounds in New York City every day.  In 1800, farmers would pay haulers to bring manure to their fields.  By 1900, there was way too much poop, and it piled up on empty lots.  Some heaps were 60 feet high (18 m).  Clouds of flies picked up pathogenic microbes and brought them to your kitchen, spreading typhoid and other fecal-oral diseases.  In 1880, 41 horses died each day on the streets of New York.  The average horse weighed 1,300 pounds (590 kg).  Carcasses were often left to rot, making it easier to dismember them, so they could be hauled away.

Horses were jammed into filthy, poorly ventilated stables — excellent disease incubators.  In 1872, the Great Epizootic Epidemic struck, as huge numbers of horses were infected by the equine influenza virus.  Coughing spread it from one animal to the next.  Typically, they recovered in two to three weeks, but severe cases could immobilize an animal for six months.

During the epidemic, available horse power was drastically reduced.  Folks had to use wheelbarrows and handcarts to transport goods.  The postal service was hobbled.  Freight piled up.  Coal deliveries stopped.  Food distribution wheezed.  On farms, plows and other equipment fell idle.  Boats quit moving on the Erie Canal.  Horse-drawn fire engines and street cars did not move.  When a big fire roared in downtown Boston, firemen had to pull their heavy equipment from the station by hand.

Almost certainly, there are people alive today who will see the peak of motor vehicle production, and I wouldn’t be surprised if some (or many) will experience the extinction of motor vehicles, and the lights going out on civilization as we know it.  Bye-bye railroads, air travel, refrigerators, elevators, irrigation, mining, supermarkets, and so on.  Sewage treatment plants, municipal water systems, and digital technology will blink out.  Vast areas of cropland will cease being plowed, planted, and harvested.  The age of obesity and cell phone addiction will end, but we might see the screw-brained revival of wood-fueled motor vehicles.

Kelekna, Pita, The Horse in Human History, Cambridge University Press, New York, 2009.

Olsen, Sandra L., “Pleistocene Horse-hunting at Solutre,” Johnson, E., ed., Ancient Peoples and Landscapes, Museum of Texas Tech University, Lubbock, 1995, pp. 65-75.

Dolní Věstonice webpage with awesome illustrations.  [LINK]

Morris, Eric, “From Horse Power to Horsepower,” Access, Number 30, Spring 2007.  [LINK]

Bartlett, Albert A., The Essential Exponential, Center for Science, Mathematics & Computer Education, University of Nebraska, Lincoln, 2004.   [LINK]

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.