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]