Friday, February 14, 2025

The Future of Mankind (Part 1)

 Let me start this essay of mine by asking which part of the human body occupies the most space while he is standing? Is it his shoulder, his abdomen, waist or feet?

The average cross-sectional area of a human body is not a readily available single value as it significantly varies depending on the body part and individual size, but for an adult, the average cross-sectional area at a typical "mid-body" section is roughly around 0.2 square meters.

The body surface area (BSA) is the measured or calculated surface area of a human body. The most widely used formula for measuring body fat in obese and non-obese patients is the Du Bois formula for estimating the approximate surface area of a body if height and weight be known.  Du Bois formula does not measure the cross-sectional area of the body. The simpler Mosteller formula is a common way to calculate a person's body surface area (BSA) in square meters but not the cross-sectional part of his body.

Magnetic resonance imaging (MRI) may be used to measure the muscle volume (MV) and muscle-size of the body and anatomical cross-sectional area (CSA), but (MRI) is a very time-consuming process.

Finally, if we know the cross-sectional area of an average person, how much space would 100 average people occupy on the ground if they were to stand shoulder-to-shoulder with each other? Let me try to answer this.

To answer the first question, the part of the human body that occupies the most space while standing is the shoulders. The width of the shoulders is generally the broadest horizontal dimension of the body compared to the waist, abdomen, or feet. The cross-sectional area of the body varies along different sections, but at the shoulder level, the body tends to be at its widest, especially in males. The next question  is the space occupied by 100 people standing shoulder-to-shoulder.

Estimating the cross-sectional area of an individual at shoulder level would be,  if we assume an average shoulder width of about 0.45 meters (45 cm) per person and an average depth (front-to-back thickness) of 0.25 meters (25 cm), then the approximate cross-sectional area at the shoulder level is:

 If we assume an average shoulder width of about 0.45 meters (45 cm) per person and an average depth (front-to-back thickness) of 0.25 meters (25 cm), then the approximate cross-sectional area at the shoulder level is:

0.45 × 0.25 = 0.1125 square meters

Calculating the total space occupied by 100 people:

If these 100 people stand shoulder-to-shoulder, they will form a single row with a total width of:

100 × 0.45 = 45 meters

The depth of the row remains 0.25 meters, so the total area they occupy on the ground is:

45 × 0.25 = 11.25 square meters

Thus, 100 average people standing shoulder-to-shoulder would occupy approximately 11.25 square meters of space on the ground.

However, according to one estimate, the source claimed that, if every person on Earth were to stand shoulder to shoulder, they would occupy an area of approximately 7,000 square miles. Is this estimate or claim correct? Let’s check this out using mathematics.

As of 2023, the estimated global population is around 8 billion people. What is the space required per person? A common estimate for the space an average person occupies while standing is about 0.1 square meters (1 square foot). This accounts for personal space and some movement.

Let's go through the mathematical calculations carefully to check it out (what was claimed  by one source) 

Step 1: Checking the Total Area Calculation

We assume each person occupies 0.1 m² while standing.

Total Area = 8,000,000,000 × 0.1 = 800,000,000 m

Since 1 square kilometer (km²) = 1,000,000 m²,

800,000,000 / 1,000,000 = 800 km²

Converting to square miles (1 km² ≈ 0.3861 mi²):

800 × 0.3861 ≈ 309 square miles

This means that if 8 billion people were standing shoulder-to-shoulder, they would only occupy about 309 square miles, not 7,000 square miles (as claimed by one source). The 7,000 square miles estimate or claim likely includes personal space for comfort rather than just tight shoulder-to-shoulder standing.

Step 2: How Many People Can Stand Shoulder-to-Shoulder on the Habitable Surface of Earth?

1. Estimating the Habitable Land Area of Earth

The Earth's total land area is about 148 million km². However, much of this consists of deserts, mountains, and ice-covered regions. The habitable land area (including forests, grasslands, and arable land) is estimated to be about 104 million km² (or 40 million square miles).

Total Habitable Land Area = 104,000,000 km² = 104,000,000,000,000 m²           

2. Maximum Number of People Standing Shoulder-to-Shoulder

If each person occupies 0.1 m², then:

104,000,000,000,0000 / 0.1

=1.04 × 1015 = 1.04 quadrillion people

or 1,040 trillion people could theoretically fit on all habitable land if they stood tightly packed, shoulder-to-shoulder.

Step 3: Population Scenarios for Earth's Carrying Capacity

Even if people could physically fit, we must consider resources, food, water, and sustainability. Here’s what happens if the population keeps growing:

Scenario 1: 50 billion people

At 50 billion, Earth’s cities would be 10 times denser than today’s largest cities.

Food, water, and energy would become the biggest challenges.

Agricultural land would be converted into urban zones, making food production difficult.

Scenario 2: 100 billion people:

Housing would need to expand vertically into massive skyscrapers or underground cities.

Water shortages and food production would require advanced hydroponics, vertical farming, and desalination.

Global climate and biodiversity loss would be severe.

Scenario 3: 1 trillion people:

Even with extreme technology like synthetic food, fusion energy, and AI-controlled ecosystems, Earth would struggle.

Living conditions would be like a mega-arcology (giant, self-contained city).

Most natural ecosystems would be destroyed.

Scenario 4: 1.04 quadrillion people (Max Density)

The entire habitable land surface would be one giant crowd.

Zero land for food, water, or movement - humans would be standing still.

A completely un-liveable scenario.

A Conclusion:

Physically, we could fit over 1 quadrillion people standing shoulder-to-shoulder on the habitable land, but sustainable living would collapse long before that.

 A more realistic upper limit with advanced technology might be 100 billion people, but even that would be a stretch.

What then shall we do as potential solutions for future overpopulation, such as space colonization or deep-sea living? We also need to consider oxygen and food supply, waste disposal, energy requirement, water pressure problems among others

Deep-sea living is a fascinating but highly challenging concept. Let me  analyse the key requirements and challenges, as well as possible solutions.

1. Oxygen Supply

Challenge:

The ocean has limited dissolved oxygen, especially in deeper regions.

People need a continuous supply of oxygen, which cannot be naturally sustained in an underwater city.

Possible Solutions:

Electrolysis of seawater: Using electricity to split water molecules into oxygen and hydrogen.

Artificial oxygen farms: Using underwater algae or engineered microorganisms to generate oxygen.

Compressed air pipelines: Supplying oxygen from the surface through pipes or airlocks.

Nuclear submarines approach: Nuclear-powered oxygen generators (as used in submarines) could be used for long-term sustainability.

2. Food Supply

Challenge:

Traditional agriculture is impossible without light.

Transporting food from the surface is expensive and inefficient.

The deep ocean lacks natural food sources for humans.

Possible Solutions:

Hydroponic and aquaponic farming: Using LED grow lights powered by renewable energy for plant growth.

Fish and seafood farming: Large-scale aquaculture of deep-sea fish, seaweed, shellfish, and plankton.

Genetically engineered food sources: Lab-grown meat and algae-based proteins tailored for underwater conditions.

Harvesting deep-sea organisms: Exploring edible deep-sea creatures such as krill, jellyfish, and certain deep-sea fish.

3. Waste Disposal

Challenge:

Waste management is crucial in a closed environment.

Direct disposal into the ocean can disrupt ecosystems and lead to pollution.

Possible Solutions:

Closed-loop waste recycling: Converting waste into energy using biogas digestion or microbial fuel cells.

Deep-sea composting: Using bacteria to break down organic waste into reusable nutrients.

Water filtration and purification: Advanced filtration systems to recycle water continuously.

4. Energy Requirements

Challenge:

Solar energy is unavailable in the deep sea.

Traditional fossil fuels are impractical due to the need for constant resupply.

Possible Solutions:

Nuclear power: Small modular reactors (SMRs) could provide continuous energy.

Geothermal energy: Using underwater hydrothermal vents to generate power.

Wave and tidal energy: Harnessing the ocean currents to generate electricity.

Hydrogen fuel cells: Storing and using hydrogen generated from seawater electrolysis.

5. Water Pressure Problems

Challenge:

Pressure increases by 1 atmosphere (14.7 psi) for every 10 meters of depth.

At 1,000 meters, the pressure is 100 times greater than at the surface.

Possible Solutions:

Reinforced habitats: Building habitats from titanium alloys, carbon composites, or transparent acrylics (like submarine windows).

Pressure equalization: Keeping internal pressure similar to the surrounding water, similar to deep-sea diving suits.

Floating cities: Instead of being at extreme depths, habitats could be anchored at mid-depths (~200–500 meters) where pressures are more manageable.

6. Psychological and Social Challenges

Challenge:

Humans evolved to live with sunlight and open spaces.

Long-term isolation and confinement could cause depression, anxiety, and social instability.

Possible Solutions:

Artificial daylight simulation: Using full-spectrum lights to mimic natural sunlight.

Large, open communal spaces: Designing underwater domes with virtual sky projections.

Frequent rotations to the surface: Allowing people to alternate between underwater and surface life.

7. Structural Design of an Underwater City

Design Concepts:

Seafloor Cities: Large, pressurized habitats built on the ocean floor with energy and oxygen self-sufficiency.

Floating Underwater Cities: Suspended at 200–500 meters below the surface, tethered to floating platforms.

Bubble Cities in Giant Domes: Transparent domes creating enclosed, breathable environments underwater.

Mobile Submarine Cities: Self-sufficient underwater vessels that move with ocean currents.

Deep-sea living is possible, but it requires overcoming technological, physiological, and logistical challenges. The best approach would be a gradual transition, starting with offshore floating platforms, then semi-submerged habitats, and eventually, full-fledged underwater cities.

Shall we explore space colonization as an alternative, or should we refine any of these deep-sea ideas further? 

But at the moment as I write, I think it may be far easier for us to control our ever-expanding population than to do suggest all those almost unimageable solutions. 

The sheer complexity, cost, and engineering challenges of deep-sea (or even space) colonization make population control a far more practical solution. Humanity's future on Earth ultimately depends on political will, cultural attitudes, and our collective desire to balance growth with sustainability.

Furthermore, I don't think we have the resources to build all these structures just because we like to increase our population.  It is much easier to implement population control. But would countries like India and Islamic countries want that? At least in China that has the world's largest population, they used to have a one-child policy, but after China found their population in declined, they now allow 3 child policy to replace their parents.  China  one-child policy slowed population growth but later led to problems like an aging workforce. Now, they have shifted to a three-child policy due to declining birth rates.

The Challenge of Population Control:

However, countries like India and many Islamic nations may resist strict population control due to cultural, religious, and economic factors:

1. Religious and Cultural Beliefs: Many societies see having large families as a blessing or necessity.

2. Economic Dependence on Large Families: In some developing nations, children are seen as an economic asset rather than a burden.

3. Political Resistance: Governments may fear backlash from citizens if they impose birth limits.

The Future of Humanity: Key Factors for Survival are:

Resource Management: Efficient use of food, water, and energy will be crucial.

Technological Innovation: Advances in vertical farming, renewable energy, and smart cities could reduce the impact of population growth.

Education and Family Planning: Empowering people (especially women) with education and healthcare often leads to natural population decline.

Global Cooperation: Countries must work together rather than compete over dwindling resources.

If humanity does not control population growth, extreme solutions like deep-sea or space living may become necessary, not optional, but at an unimaginable cost. Do we think  governments will ever truly take global population control seriously, or will they wait until it's too late? The fate of humanity on this limited world of ours depends on political will and our desire to survive.

But I  think humanity will destroy itself politically through wars, political and social unrest, economic disruption, shortage of agricultural land for food, water fuel and energy supply, limited space for living, unemployment, congestion, pollution, climate change, earthquakes, floods, massive wild fires and other unpredictable destructive elements such as a massive asteroid smashing up this earth as it did to the dinosaurs that went extinct about 65 million years ago (at the end of the Cretaceous Period), after living on Earth for about 165 million years.

I don't think humanity can exist that long for us to start to explore and colonize other worlds, live under the seas or on the top of them in boats or other structures. Our unbecoming behaviour adverse to the existence of life would have long destroyed us. No other animal or life sharing this home with us do the same as we, basically and zoologically as human animals. No other animal sharing this world with us do things like we do.   

Humanity, despite its intelligence, often acts in ways that threaten its own survival. Unlike other species that coexist with nature, we seem to be accelerating our own destruction through war, greed, environmental destruction, and short-sighted policies.

The Self-Destruction Hypothesis

If we examine history, civilizations have collapsed due to:

  • Political instability (wars, revolutions, corrupt governance)
  • Resource depletion (food, water, energy crises)
  • Climate change and natural disasters
  • Economic failure (collapse of trade, unemployment, hyperinflation)
  • Pandemics and bioweapons (plagues, engineered viruses)

The world today is facing all of these simultaneously, at an unprecedented scale. Unlike past civilizations, which collapsed in isolated regions, today's world is interconnected—a crisis in one area can have global consequences.

Colonization of Other Worlds: A Fantasy?

It is  questionable  whether humanity will even survive long enough to colonize space or the deep sea. The idea of escaping to Mars, for example, is unrealistic when we can’t even manage Earth properly. The costs, risks, and technological challenges make it seem like an unlikely backup plan.

A Race Against Time

At this rate, the real question is: Can we change before it's too late?

  • Will we prioritize cooperation over conflict?
  • Will we stop depleting the Earth's resources?
  • Will we control our population and waste?

Or will we destroy ourselves before we get the chance to find a second home?

(I shall try to answer this dilemma of ours in Part 2 of this essay. Probably this article may stretch up to 5 or 6 parts? I do not know myself. I can only continue to write as my thoughts continues to flow).  

No comments:

The Final Fate of Humanity (Part 4)

  By: lim ju boo Summing up my  essays on “The Fate of Humanity”,  I must say, these realities of overpopulation are both profound and sob...