Showing posts with label overheating. Show all posts
Showing posts with label overheating. Show all posts

Saturday, August 14, 2021

Wild Free and Happy Sample 56

 

[Note: This is the fifty-sixth sample from my rough draft of a far from finished new book, Wild, Free, & Happy.  The Search field on the right side will find words in the full contents of all rants and reviews.  These samples are not freestanding pieces.  They will be easier to understand if you start with sample 01, and follow the sequence listed HERE — if you happen to have some free time.  If you prefer audiobooks, Michael Dowd is in the process of reading and recording my book HERE.

[Continued from Climate Crisis 01 Sample 55]

Super Seeps

Valeria Sukhova and Olga Gertcyk wrote an update on sea floor methane seeps.  Scientists have been doing research in the Laptev and East Siberian seas, where there are large deposits of offshore permafrost and methane hydrates.  Numerous seeps are releasing methane into the atmosphere.  In the air above the water’s surface, methane levels are 16 to 32 ppm (parts per million).  This is 15 times higher than the average methane content for the world atmosphere. 

Over a thousand large seep fields (super seeps) have been found so far.  “They probably are not having a large impact on atmospheric CO2 or methane yet.”  Meanwhile, the Arctic climate is rapidly warming, the ice continues melting, the water continues warming, and there are large deposits of seabed hydrates that have not yet thawed. 

Methane Craters

Methane craters are massive holes in the tundra that are caused by methane explosions.  As the climate warms, thawing permafrost leads to methane releases that can accumulate in underground pockets.  The holes are also called gas emission craters, blowout craters, funnels, and hydrolaccoliths.  Methane craters not the same as thaw slumps caused by subsidence, when the land surface softens and sinks due to thawing permafrost.  Slumps sometimes fill with water, creating lakes or ponds.

Anna Liesowska reported that methane craters are a recent surprise, appearing on the Yamal and Taymyr (Gyden) peninsulas of northern Siberia.  The first one was discovered in 2014, by a plane passing over tundra in the middle of nowhere on the Yamal peninsula.  Until this sighting, these craters were unknown.  She mentioned this 2014 discovery in a July 2020 article that announced the discovery of the seventeenth methane crater.  It was about 164 feet (50 m) deep. 

Her article included a number of stunning photographs.  They included two photos of pingos, large mounds created by rising pressure.  The Pingo article in Wikipedia will further illuminate your understanding.  Pingos are only found in permafrost regions.  There may be 11,000 of them on Earth.  One region in Canada has permafrost that’s more than 50,000 years old.

Richard Gray created an excellent article for the BBC.  It is recent (November 2020), provides a deeper discussion of methane craters, and includes a number of dramatic photographs.  Satellite images, taken over multiple years, indicate that the site of the seventeenth crater (2020) had previously been a pingo that first appeared in the autumn of 2013.  In northwest Siberia, the exploding pingos are apparently created by concentrated pockets of methane, and they develop in a few years.  They are located in regions located above deep deposits of gas and oil. 

The explosions can be very exciting.  “Local reindeer herders reported seeing flames and smoke after one crater explosion in June 2017 along the banks of the Myudriyakha River. Villagers in nearby Seyakha — a settlement about 20.5 miles (33 km) south of the crater — claimed the gas kept burning for about 90 minutes and the flames reached 13 to16 feet (4 to 5 m) high.”

In this region of northern Siberia, satellite images taken from 1984 to 2007 indicate a five percent change in the landscape, as the climate warms, and more permafrost thaws.  The Arctic is warming twice as fast as the global average, so permafrost will continue thawing in summer months, and more methane will be released.  How many more craters will explode in the coming years?  How much more methane will be released into the atmosphere?  Also worrisome is that craters are exploding in a region of gas and oil extraction.  There are many pipelines running across the land, and some are close to pingos.  There is potential here for eco-catastrophes. 

Portia Kentish reported on impacts caused by the 2020 heat wave in Siberia, “where melting permafrost means the ground is no longer able to support structures built on it.  For many, this raises particular concerns over the oil and gas industry, which is the primary economic sector in the Arctic Circle.  Pipelines, processing plants and storage tanks on unstable and thawing ground become a serious threat to the natural environment.”

In 2019, the Intergovernmental Panel on Climate Change (IPCC) released a report.  It found that “45 per cent of oil and natural gas production fields in the Russian Arctic are located in the most hazardous and at-risk region.  Moreover, areas of discontinuous permafrost could see a 50-75 per cent drop in load bearing capacity over the period from 2015-25 in comparison to 1975-85.”  Stuff like roads, bridges, power grids, and towns are vulnerable. 

Undersea Craters

Nancy Bazilchuk reported on research in the Barents Sea, which is a region of the Arctic Ocean located between Norwegian and Russian territorial waters.  In the 1990s, scientists discovered craters that blew out of the seafloor 12,000 to 15,000 years ago.  Recent research has discovered hundreds more ancient craters.  Some are 300 to 1,000 meters (328 to 1093 yards) in diameter, and blasted out of solid bedrock.

Karin Andreassen and team have been doing this undersea research, and they published a very detailed paper.  Over the eons, there have been numerous glaciations (ice ages).  When regions freeze, methane is trapped beneath ice sheets, and solidifies into methane hydrates.  When warm periods return, some of the frozen methane can thaw and be released.  Releases can be gradual, in streams of bubbles, or they can be abrupt, with crater-making explosions. 

The incredible genius of humankind now allows us to cleverly disrupt the climate in a remarkable number of ways.  Andreassen assures us that there are still enormous amounts of methane stored in sea beds and terrestrial permafrost.  “It is apparent that extensive sub-glacial hydrate accumulations exist beneath the Antarctic and Greenland ice sheets today.”  She expects more methane craters will explode. 

Life as we know it is moving into the rear view mirror.  The Hot Age just got out of bed, yawning, making coffee.  Nobody knows how hot it will get, how long it will last, and what it will remain when it’s over.

Ocean Heating

Cheryl Katz discussed how oceans have been softening climate impacts by soaking up excess heat that has been trapped in the atmosphere by greenhouse gases.  By keeping the atmosphere a bit cooler for a while, this has delayed our inevitable head-on collision with reality.  Currently, up to half of our CO2 emissions are absorbed into seawater.  Also, heating up the oceans has accelerated acidification and deoxygenation (more on these below). 

Experts are learning that the surface waters are now warming faster and deeper than ever.  The situation was worse than they thought.  Heat gain had been underestimated by as much as half — too little attention had been devoted to the Southern Hemisphere, where 60 percent of ocean water resides.  Most of the heat gain was happening well south of the equator.  At the same time, the Arctic Ocean is heating especially fast, as its ice cover melts and shrinks. 

When water gets warmer, it expands.  So, warmer oceans contribute to higher sea levels, as does the huge volume of water flowing out of melting glaciers and icepacks.  The art of accurately predicting upcoming sea level changes has yet to be perfected.  The world is far more complex and capricious than the programmers of computer models can imagine.  There are limits to how much heat oceans can store.  As their ability to absorb heat maxes out, they may stop absorbing heat, and begin releasing stored heat into the atmosphere.

Paul Ehrlich and John Harte noted that in a warming climate, higher ocean temperatures can power more intense storm events, and the warmer atmosphere has the capacity to store more water, so rainstorms are more intense.

Tierney Smith notes that oceans absorb between 35 and 42 percent of CO2 emissions.  They also absorb around 90 percent of the excess heat energy that results from the warming climate.  This elevates surface temperatures, and a warmer surface will absorb less of our CO2 emissions.  So, more carbon will continue to accumulate in the atmosphere, further warming the planet.

Timothy Lenton wrote, “Ocean heatwaves have led to mass coral bleaching and to the loss of half of the shallow-water corals on Australia’s Great Barrier Reef.  A staggering 99% of tropical corals are projected to be lost if global average temperature rises by 2°C, owing to interactions between warming, ocean acidification, and pollution.  This would represent a profound loss of marine biodiversity and human livelihoods.”

Todd Woody reported on the findings of the IPCC’s 2019 Special Report on the Ocean and Cryosphere in a Changing Climate.  It noted that the rate of ocean warming has doubled since 1993.  Extreme flooding of coastal areas will likely occur at least yearly by 2050.  Fish populations face collapse thanks to a combination of ocean acidification, loss of oxygen, and warming of the ocean’s surface, which blocks the flow of nutrients to and from the deep sea.

Ocean Deoxygenation

Karin Limburg reported that oxygen levels in the oceans have been declining for about 70 years.  This is gradually suffocating saltwater ecosystems (“oceans are losing their breath”).  Low oxygen conditions exist in a number of coastal sites, semi-enclosed seas, and the open ocean.  At the extreme, the Baltic Sea has regions of water with too little oxygen to measure (anoxic).

More than 700 coastal sites are experiencing low oxygen conditions (hypoxic).  They are overloaded with nutrients, like nitrogen and phosphorus, runoff from fertilizer and sewage.  We call them dead zones, but they aren’t completely dead.  They are home to large mobs of wee microbes that thrive in nutrient rich water.  Algae (phytoplankton) are wee aquatic plants that feast on the nutrients, explode in number, and create algal blooms.  In the process, they emit lots of oxygen.  When the nutrients run low, the algae die and decompose.  Then, blooms are often followed by a surge of wee aquatic animals (zooplankton) that feast on the rich stew of dead algae and absorb the abundant oxygen.  Depleted oxygen = dead zone.

Polluted water is not caused by climate change, it’s the result large swarms of untidy primates that dump staggering amounts of crud into waterways.  Skanky water is one cause of deoxygenation.  Another cause is climate change, which is affecting open waters that are not nutrient rich. 

Rising temperatures make water close to the surface warmer and lighter, which intensifies thermal stratification.  This reduces the mixing of warmer surface water with deeper water that is denser and colder.  Colder water is able to absorb more oxygen, but the warmer water above inhibits its exposure to airborne oxygen.  Also, climate change is melting more and more ice, sending lots of freshwater into the salty sea.  Freshwater is less dense than salt water, so it stratifies above colder, deeper water — another obstacle.

So, compared to earlier times, less oxygen is now available in deeper waters.  Some sea animals are able to survive in zones of minimal oxygen, others are forced to move.  Animals having a high metabolism, like tuna or sharks, move to shallower depths, where they are more likely to be caught.  Migration introduces some chaos into traditional food webs, as more species become crowded together.

Ocean Acidification

Cody Sullivan and Rebecca Lindsey of the National Oceanic and Atmospheric Association (NOAA) wrote about how oceans are being affected by human-produced CO2.  Oceans are the only long-term sink for manmade CO2 emissions.  Colder waters tend to absorb CO2, while warmer waters tend to release it back into the atmosphere.  Since 2000, the overall net increase in CO2 absorption has been trending upward at a robust rate.  Unfortunately, the higher uptake of carbon also encourages ocean acidification.

Cheryl Katz studies ocean acidification (“global warming’s evil twin”).  In the Arctic, and in the Southern Ocean surrounding Antarctica, lots of ice is busy melting away, exposing the water below.  In cold polar waters, CO2 is more soluble, so more of it can be absorbed.   Some of it reacts with the water to form carbonic acid.  Consequently, the frigid waters near both poles are becoming highly acidified.  Conditions in the polar regions are getting close to a tipping point into extreme acidification.

The area of increasingly corrosive water is expected to expand into the North Atlantic and North Pacific, impact the ocean food web, and threaten important fisheries.  Already, oysters are dying off in the U.S. Pacific Northwest.  Shell-building organisms need carbonate minerals.  In the past, carbonate ions in the water provided a buffer against the acids.  As these ions are depleted, acidity is able to rise.  Creatures with shells are having a harder time building and maintaining shells, because they corrode.

Increasing ocean acidification is a severe threat to the planet.  It is expected to have a big impact on fisheries in Alaska and throughout the Arctic.  As waters warm, species like Atlantic cod are migrating toward the cooler Arctic, where acidification is high.  Fish populations are likely to decline, impacting the global food supply for humans.

Stephanie Dutkiewicz and team studied the impact of acidification on phytoplankton (algae), the tiny plants that are the foundation of the marine food web.  They absorb CO2 and emit the life-giving oxygen that’s necessary for the existence of animal life.  Oceans absorb about 30 percent of manmade carbon emissions, and this intensifies acidification.  Their analysis concluded, “At the level of ecological function of the phytoplankton community, acidification had a greater impact than warming or reduced nutrient supply.”

Dahr Jamail noted that “phytoplankton photosynthesis produces half the total oxygen supply for the planet.”  Growing acidification will eliminate some species, and disturb vital ecological balances.

Thermohaline Circulation

Ocean current circulation is a very big deal.  It has a major impact on regional climates, because it moves heat.  In plain English, it’s called the global conveyor belt.  In science speak, it’s called the thermohaline circulation (THC).  The THC moves heat around the world via a long and winding pathway.  Wikipedia provides a nice plain English description of the THC [HERE].

The flow of the current is driven by seawater density, which is determined by variations of surface temperature and salt content (salinity).  Warm water is less dense than cold, so it rises to the top.  Freshwater is lighter, less dense, so it stays close to the surface.  Salt water is denser and heavier. 

Today, melting ice sheets, glaciers, and sea ice are pouring huge amounts of cold freshwater into the ocean, which throws a monkey wrench into the traditional operation of the current.  Global warming will increasingly have an impact on ocean circulation.  These changes are expected to eventually alter the traditional patterns of the THC as we know it.  Some experts are contemplating the possibility of a slowdown or shutdown of the THC.  Wikipedia discusses the possibilities [HERE]. 

Atlantic Meridional Overturning Circulation (AMOC)

One segment of the global thermohaline circulation is the Atlantic Meridional Overturning Circulation (AMOC).  As the name implies, this involves the currents moving north and then south in the Atlantic Ocean.  The AMOC is fed by warm and salty water flowing past the cape of Africa, heading northwest to the Caribbean, then up the coast of North America, then northeast to Iceland and Scandinavia.  In the far north, the current loses much heat, and sends cool water back down toward the South Pole.

The segment of the AMOC that moves warm water from the Gulf of Mexico toward the Arctic is called the Gulf Stream.  It keeps the climate of the eastern U.S. and northern Europe warmer than is typical at such a high latitude.  This allows modern agriculture in these regions.  Some worry that the melting arctic will increase the frigid freshwater flowing into the AMOC, and this could lead to a slowdown or shutdown of the current, and possibly a chillier future for the eastern U.S. and western Europe. 

Some have presented evidence that the AMOC is slowing down.  Others don’t find this evidence to be compelling, and they don’t expect a slowdown in the near term future.  Much is not known about ocean currents, and controversies abound.  Scientists are far from full agreement on what is happening, and what might happen in the future.

Nicola Jones wrote an easy to understand description of current AMOC research and debates.  Undersea instruments that measure the current’s flow are indicating a significant slowdown.  Experts aren’t sure if this is worrisome evidence of climate change, or simply reflects normal variations. 

“Should the AMOC shut down, models show that changes in rainfall patterns would dry up Europe’s rivers, and North America’s entire Eastern Seaboard could see an additional 30 inches (76 cm) of sea level rise as the backed-up currents pile water up on East Coast shores.”  This hasn’t happened yet.  For now, data collection continues, and the debates rumble on.

Overheating

David Wallace-Wells wrote that the five warmest summers in Europe since 1500 have all occurred since 2002.  Rising heat will have the most dramatic impacts in the Persian Gulf and Middle East, where record temperatures have soared to frightening heights.  In 2015, temps as high as 163°F (73°C) were recorded.

Matthew Lewis described how rising numbers of people are dying because extreme heat events are becoming more common.  “Deadly heat is cooking us alive.”  When our bodies get too warm, we sweat, which helps us shed excess heat as it evaporates.  If you’re lucky, this keeps your body temperature in the normal range. 

We evolved our ability to sweat on African savannahs, where the humidity is typically low (“dry heat”).  So, we can survive for a few hours of 120°F (49°C) in Death Valley, California.  It’s a different story in super-humid Florida, where “a single day of 120-degree temperatures in Palm Beach would be a mass casualty event.  Dead bodies would pile up in the morgues, victims of hyperthermia, or heatstroke — cooked, alive, in their own bodies.”  Alas, the cooling powers of sweating have limits.

Tara Santora explored the maximum amount of heat that the human body can endure.  Air temperature is the scale of heat that a thermometer displays.  Wet bulb temperature is produced by a thermometer covered in a water-soaked cloth.  It takes into account both air temperature and the humidity level.  She reported that the limit we humans can endure is a wet bulb temperature of 95°F (35°C).  You probably wouldn’t last three hours.

When the air temperature is 115°F (46.1°C) and humidity is 30%, the wet bulb temperature is 87°F (30.5°C).  When the air temperature is 102°F (38.9°C) and humidity is 77%, the wet bulb temperature is 95°F (35°C).  When the wet bulb temperature is close to your normal body temperature, you still sweat, but this doesn’t cool you.  You can also overheat at lower temperatures if you are exercising and/or exposed to direct sunlight.  As the climate warms, the risks of overheating increase. 

Janet Larsen noted that a warming climate is expected to increase the number and intensity of heat waves in the coming years.  In 2003, a blast furnace heat wave caused the deaths of more than 52,000 people across Europe.  It was the hottest weather in at least 500 years.  Temperatures were over 104°F (40°C) for up to two weeks.  Fatalities rose to 2,000 per day in France.  The higher the humidity, the higher the death rate.  City folks were most at risk, because urban areas are heat islands.  Jean-Marie Robine and team did additional research and estimated that the actual mortality in 2003 was more than 70,000.

John Gowdy added, “During the record heat in Europe in Summer 2003, maize production fell by 30% in France and 36% in Italy.  A 2008 study found that southern Africa could lose 30% of its maize crop by 2030 due to the negative effects of climate change.  Losses of maize and rice crops in South Asia could also be significant.”

Extreme heat dries out the land, making it more flammable.  Wikipedia noted that the 2003 European heat wave corresponded with a series of fires in Portugal that destroyed 1,160 square miles (3010 km2) of forest, and 170 square miles (440 km2) of agricultural land.  In southern Portugal, the temperatures reached as high as 117°F (47°C). 

Deepa Shivaram reported on a heat wave that hit British Columbia in July 2021.  Along the coastline of Vancouver, on one beach alone, the rocky shore was covered with hundreds of thousands of dead mussels.  It also killed barnacles, clams, crabs, sea stars, and intertidal anemones.  Overall, an estimated one billion sea creatures died from the heat.  Other animals that depend on sea life for food were also affected.  During the same heat wave, 180 wildfires ignited.

[Continued in Climate Crisis 03, Sample 57]

Wednesday, January 2, 2019

Wild Free and Happy Sample 06

[Note: This is the sixth sample from my rough draft of a far from finished new book, Wild Free & Happy.  I don’t plan on reviewing more books for a while.  My blog is home to reviews of 199 books, and you are very welcome to explore them.  The Search field on the right side will find words in the full contents of all rants and reviews, if you are interested in specific authors, titles, or subjects.] 

Bipedal Locomotion

Baboons survive today because their ancestors evolved a successful approach for living on the savannah.  They did this by organizing into powerful bad ass gangs.  Like all other non-human animals, baboons still survive by living in the manner for which evolution has fine-tuned them, free from addictions to crutches like fire or complex weapons.  They stayed in their tropical homeland, and could possibly remain there for another million years, if the human turbulence in their ecosystem mercifully mellowed out.

Unlike baboons, our ancestors took a radically different approach to surviving on tropical savannahs.  They quit knuckle walking, evolved an upright posture, and became bipedal — standing, striding, and sprinting on two legs, not four.  This transition reduced or eliminated their ability to quickly scamper up trees, where they were less vulnerable to predators.  So, a new category of primates was born: hominins — bipedal ground-dwelling primates. 

The earliest bipedal primate is the subject of controversy.  It may have lived as early as 6 million years ago.  By about 4 million years ago, our ancestors’ feet had become less useful for grasping (climbing trees), and more attuned for walking smoothly.

In Tanzania, 3.6 million years ago, two bipedal ancestors left their footprints in wet volcanic ash.  In 1978, at the Laetoli site, scientists discovered 70 of their fossilized footprints, in a sequence that was 88 feet long (27m).  These ancestors were probably Australopithecus afarensis.

Why the shift to bipedal travel?  Over time, as climate change expanded grassland, the distance between groves of trees increased.  Knuckle walking is OK for short trips, but striding is more comfortable and energy efficient for longer journeys.  Standing upright provided a better view of the surroundings.  It also made them more visible to hungry predators.  It freed up their hands for carrying things like food, water, infants, embers, and tools.

For brief high-speed getaways, hominins were far slower than galloping chimps.  Alfred Crosby noted that bipedal striding is like walking on stilts, and it increases the odds for falling down.  Four-legged critters (quadrupeds) like canines, cats, or horses move in a manner that is far more graceful, stable, and speedy.

On the savannah, evolution typically selected for prey animals that were better high speed escape artists.  Consequently, it also selected for the predators that were more effective at killing them.  If prey gradually got larger, predators gradually got larger.  If prey got faster, so did the predators.  If prey got too good at surviving, they would overgraze the savannah and starve.  If predators got too good at hunting, they would eliminate their prey and starve.  The ecosystem was an endless bloody evolutionary soap opera.

With regard to our ancestors, evolution advanced an unusual mutation.  Instead of size or speed, it selected for heat tolerance and long distance running.  Compared to four-legged critters, standing upright exposed less of their bodies to hot sunbeams, and their bushy hairdos provided extra heat protection.  Their nearly furless bodies, equipped with three million juicy sweat glands, allowed them to shed body heat better than other savannah mammals. 

Tree-dwelling primates enjoyed a diet majoring in fruit, which grew all around them, all year long.  On the savannah, there was less fruit, so foraging required travelling farther, and finding other things to eat.  Some believe that our ancestors became bipedal to improve their success at scavenging — beating competitors to fresh carcasses.  Bernd Heinrich wrote that at Yellowstone Park, dead animals are reduced to a pile of bones in just seven hours.  In Africa, hyenas devour the bones too.

The person you see in the mirror has a body that is optimized for running, not walking.  Your toes and heel tendons provide a bounce when your foot hits the ground, improving energy efficiency.  Your legs and spine are fine-tuned for jogging, keeping your head and eyes steady.  Skilled runners gracefully glide along, lightly skimming across the land.

The shift to bipedal locomotion resulted in some radical changes in our ancestors’ skeletons.  Notably, the pelvis got narrower, which reduced the size of the birth canal — the passageway through which fetuses pass during birth.  This challenge was dealt with in two ways.  (1) Birth occurred earlier, when brains were smaller and less mature.  This extended the duration of childhood, the spacing between births, and the need for extended parental oversight.  (2) Since bipeds no longer slept in the trees, they could grow heavier and bigger.  Increased size was an asset for hunting and defense.  Longer legs enabled longer strides, which boosted running speed.  Larger bodies retained water better, delaying dehydration.

Bipedal locomotion was an unusual evolutionary experiment.  Few if any humans still live in the manner for which evolution fine-tuned us, a practice known as persistence hunting.

Persistence Hunting

On the savannah, predators made speedy attacks, and their prey attempted quick getaways, but both soon had to find shade and chill out, because bursts of high exertion promptly led to overheating.  Consequently, predator attacks were resolved quickly.  If a charging lion failed to promptly take down its target, the attack ended, and the prey might live to see another day. 

Our ancestors gained the ability to engage in steady long distance running, hour after hour, in the oven-like midday heat of tropical savannahs.  Once a chase began, the prey animals immediately scattered.  The hunter quickly selected an animal that was less strong and speedy, and began trotting after it.  Even when the prey was miles ahead, the hunter would doggedly follow its trail, reducing its ability to rest and cool off.

Persistence hunting requires no weapons.  Hunters must possess a deep understanding of animal behavior, great skill in the art of tracking, an intuitive mind, a healthy body, and sufficient water and nutrients for a long run.  Kalahari people had exceptional tracking skills.  Women were as good as men, or better, at interpreting spoor.  At the end of a successful pursuit, the prey might collapse from exhaustion or heat stroke, or simply stop running.  If the hunter found it still alive, he could suffocate it or bonk it on the head. 

Liebenberg was maybe the first civilized person to participate in persistence hunting (he nearly died from heat stroke).  He observed a six and a half hour chase that covered 21.7 miles (35 km), on a day when the temperature ranged between 89°F and 107°F (32°C and 42°C). 

He noted that tracking encouraged wild people to develop heightened abilities for intuitive thinking, because the tracks of their prey were rarely clear and complete.  Knowledge of animal behavior helped to fill in the blanks and suggest the most likely escape route.  The mental process was fast, automatic, effortless, and often unconscious.  Intuition also enhanced social relationships.  Wild people were far more sensitive to each other than folks in the modern world, whom Liebenberg saw as being severely handicapped by shallow or dysfunctional relationships.

Maybe our ancestors learned persistence hunting from hyenas, who hunt in packs, using their super-sensitive noses to follow animals until they are exhausted.  Or, maybe they first learned by chasing small, slow moving critters.  Somehow, maybe several million years ago, our hominin ancestors learned the clever trick of using overheating and exhaustion as deadly weapons — and the keys to survival.

Every gardener who has experienced backaches or sore knees, is painfully aware that evolution did not fine tune hominins for spending long hours on their knees or bent over, engaged in tedious repetitive movements — digging, cultivating, planting, weeding, picking, threshing, grinding, and so on.  What you see in the mirror is a body optimized for long distance pursuits across hot African savannahs — a meat-loving hunter and forager.

Bears have never forgotten their identity, consequently they confidently continue to live like bears, which is why they remain perfectly sane, and have no need for psych meds.  The same can be said for all the wild animals alive today.  The glaring exception is a super large mob of modernized persistence hunters who have become extremely disoriented by memory loss.

Young children, even in the deepest darkest McMansion suburbs, are fascinated by bears, lions, horses, bunnies, piggies, and others.  They play with teddy bears, pretend to be horses, and love looking at animals in picture books.  The kids are animals, and their hominin ancestors have been fascinated by animals for six million years.  Sadly, most will spend their lives in a reality where most of the animals they’ll closely experience will be thoroughly domesticated critters purchased for companionship or status display.

Jung said that we still retain unconscious memories of our arboreal past, when falling out of trees caused big fear.  Many of us have suddenly awakened with a gasp when a dream included a sudden plunge.  Nightmares commonly involve being chased or attacked by dangerous predators.  In crowded movie theaters, when the woman is about to be stabbed by a psycho killer, the hall explodes with loud squeals and screams, like our primate ancestors in a distant rainforest.

Over the last six million years, every species of bipedal primate has gone extinct, except one — and almost all of us have abandoned persistence hunting as a routine component of basic survival.  Don’t worry.  Close your eyes and imagine what humans might become if we spent the next 200,000 years sitting on couches, staring at glowing screens, washing down greasy pizza with fizzy sugar water.

Running Goes Global

By and by, as hominins spread far beyond the savannahs of tropical Africa, so did persistence hunting.  It spread around the world, because it works, and because evolution fine-tuned us for doing it.  For almost the entire hominin saga, we lived on our feet.  Running was a key factor in our ancestors’ survival, until we got wheels, four legged slaves, and other weird and troublesome things.

Tim Flannery reported that the Aborigines of Western Australia would pursue an individual kangaroo until it was overheated and exhausted.  The chase could take several days.  Johann Kohl wrote that the Ojibway would often run down elk, especially in the winter, when deep snow soon wore out the animal.  Hunters on snowshoes could pursue the animal for hours.  Kohl also mentioned a Sioux hunter who chased a bear to exhaustion.

Bernd Heinrich wrote about the Penobscot tribe chasing down moose, and the Navajo and Paiutes wearing out pronghorn antelopes.  In Southern Africa, hunters chased steenbok, gemsbok, wildebeest, zebras, and others.  Wendell Bennett wrote about the Tarahumara people of Mexico pursuing deer and turkeys until they collapsed.  

Peter Nabokov noted that some Tarahumara lads could run 170 miles (273 km) without stopping.  Mexicans would hire them to capture wild horses, sometimes chasing them for two or three days, until the horses could run no more — while the men remained fresh.  Nabokov quoted a Hopi man: “Long ago when the Hopi had no sheep, no horses, no burros, they had to depend for game-capturing on their legs.”

Nabokov provided numerous accounts of Indian messengers traveling great distances.  One ran 50 miles in six hours.  A Mojave lad ran 200 miles (322 km) in 24 hours.  Seven days a week, a Tarahumara man ran a 70 mile (112 km) route, carrying a heavy mailbag.  After running 15 miles (24 km), Zuni runners still had a slow heart rate and no signs of fatigue.  Men in their seventies continued to have tremendous endurance, as well as low blood pressure.

For wild people in open country, running was essential for communication, warfare, hunting, ceremonies, and rituals.  Apache boys of 8 to 12 years old regularly ran to improve their endurance and pain tolerance.  They ran carrying big loads, and they ran up mountains.  Apache warriors were much stronger and braver than the U.S. Army lads sent to exterminate them.

Nabokov wrote that 4-year old Navajo boys had to get up before sunrise every day and run four miles before having breakfast.  Speed and strength were essential when attacking enemies, or being attacked.  No one will help you in this world, you must run to get strong.  Your legs are your friends.

I spent many years sitting indoors at school desks, learning reading, writing, and arithmetic, loading my brains with the ideas necessary to be an obedient, punctual, productive cog in the industrial society that’s pounding the planet to pieces.  Wild Native Americans, during the years of their youth, were being taught to be strong, brave, and extremely healthy.  They learned the skills needed to survive in their ecosystem, in a low impact manner.  During their entire lives, they sent nothing to landfills.