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Chapter 2:

The Human Ecosystem

Our Journey from Sustainable Abundance

to Overpopulation

Throughout history, plants, animals, fish, and birds lived in relative harmony with each other. They all strived to survive on an even playing field. It was a healthy ecosystem that allowed for the most adaptable species to flourish over time.

‘The Stone Age’ (1882-1885), detail of a Painting by Viktor M. Vasnetsov

That was true until about 10,000 years ago when one species, Homo Sapiens (Humans) left its place in the natural order of things and began a journey where it now lords over all other lifeforms on Earth. Man’s impact on the natural world has become significant enough to qualify as one of only 6 geological epochs to occur since the beginning of time. It has been given a name: The Anthropocene. [1] Unless we realign with the environment around us, we face an increasingly difficult future.


Since the origin of our species some 300,000 years ago, [2] homo sapiens have migrated from their birthplace in central Africa to every corner of the world. [3] Wherever we traveled, from tropical rainforests to barren deserts to the arctic tundra, we were able to adapt to whatever our surroundings were and ultimately found a way to survive.

Scientific evidence indicates that small nomadic groups of herders and hunter-gatherers were the social norm from our beginnings. Small tribes (between 20 & 200 people) never tended to put a strain on their ecosystems. They were a part of that “balance-of-nature” wherever they went.

Human Migration from Our Beginnings

Courtesy Business Insider

After hundreds of thousands of years, man’s symbiotic relationship with nature seemed to abruptly undergo a fundamental, systemic, and behavioral change; one that represented a dynamic split from the rest of the natural world. This was the time in our evolution when the small tribal groups that had always migrated from place to place began to settle down in permanent, static locations. En-masse, they began to build durable, long lasting structures in which to live. Instead of herding, hunting, and gathering their food as they had for millennia, they began altering the areas in which they lived to suit their own needs by clearing fields, forests and cultivating crops on which they would survive. This period is known as the Neolithic or Agricultural Revolution which began approx. 8,000-10,000 BCE.

Over time these settlements evolved from small tribal camps to villages, then to towns, which coalesced into cities, and eventually groups of cities organized to form nation-states. The net result was that humans began to regard the world around them as something they “owned” vs. an ecosystem that they shared. They behaved as though they had risen above nature and held no responsibility to it beyond what served their own interests.

Tribal Groups

From that point forward they slowly reshaped the world for their sole economic benefit. It seems that any material concern for how this affected their surrounding ecosystems or the life within them became increasingly insignificant.

This mindset prevailed as the human footprint spread around the planet for thousands of years, all the while growing greater food supplies and thus their populations. Even so, the energy they used never exceeded what is known as “the carrying capacity” of the areas in which they lived and only using the stored sunlight held within what was living at the time.  [4]

Since energy is defined as the ability to do work and virtually all energy originates with the sun (with few exceptions) we have leveraged the energy that comes from sunlight in the food we eat and have used energy to do work in the form of animals. [5] With the discovery and control of fire some 1.5 million years ago along with the development of tools, we learned to harness recently stored sunlight to do work outside our own bodies. Later we learned how to tap into the energy that contained in wind, rivers, and streams to do the more of the work we’ve wanted to get done.

Estimates suggest that the Earth’s total human population at the dawn of the Agricultural Revolution was between 6 to 10 million people. Over the next 10,000 years the global population grew to approx. one billion people. By and large, humans’ resource consumption still remained within the “carrying capacity” of the regions within which they lived.

This remained true until the early 19th Century when large scale coal mining and mineral exploitation began in England and thus spurred on The Industrial Revolution. [6] The industrialization of human existence created continuously growing markets for trading goods and services, which, in turn, demanded more and more energy more and more raw materials.

Industrial Revolution

To supply the energy needed to process the increased production, coal became the energy resource of choice. That increase in energy led to a corresponding increase in the amount of food produced and then logically, the number of people that it supported. By 1850, just before commercial petroleum was discovered in the United States, the global population had grown to approx. 1.2 billion people or another 20% in just 100 years.

From the origin of our species, it took approximately 300,000 years for us to grow our population to that degree. Contrast that with the fact that in 2000, just 150 years later, our population was approx. 6 billion, a growth of 6 times.

Today, in 2020, with the population nearly 2 billion more than just 20 years ago, we are consuming raw materials and discarding waste at a rate that threatens our very existence. How long can adding the same number of people that once took 300.000 years to achieve in 10 years or less? We can’t.

Earth's Human Population is increasing by more than 200,000 people per day

It’s reasonable to conclude that our population is only going continue increasing from here. Preparing for that eventuality, especially on an isolated island in the middle of the Pacific Ocean, will require foresight, planning and wisdom.

SEH is committed to playing an integral role in the ongoing conversation to determine the sustainable [7] energy systems our community will need so our community may stay vibrant and healthy for years to come.




[2]  (CNN, 2017) The oldest fossil remains of Homo sapiens, dating back to 300,000 years, have been found at a site in Jebel Irhoud, Morocco. This is 100,000 years older than previously discovered fossils of Homo sapiens that have been securely dated. The discovery was presented in a study in the journal Nature.


[4] The “carrying capacity” of an environment is the maximum population size of a biological species that can be sustained in that specific environment. This is ultimately regulated by the average seasonal sunlight (raw energy) available to be transformed by plants into biological energy. That energy is transferred from plants to animals and animals to animals by eating one another. This process is a continuous transfer of energy from lifeform to lifeform, all of which originates with our sun.

[5]  Exceptions are: wave, nuclear, geothermal (which is literally the “sun” inside the Earth)

[6]  The Industrial Revolution occurred across America and Europe during the 18th and 19th centuries

[7]  Sustainability is the ability to exist constantly. To be sustainable we must learn to live within our entire systems’ carrying capacity. By definition, continuous growth is impossible.

Next - Chapter 3: “The Global Energy Status”  

Energy, is the oxygen for the global economy and our options are changing fast.

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