From Hunter-Gatherers to Modern Humans

 

FROM HUNTER-GATHERERS TO MODERN HUMANS: HAVE WE GAINED A LONGER LIFE OR A MORE COMPLICATED ONE?

Human longevity, mortality, healthcare, social demands, and the price of civilization

Introduction: The Paradox of Human Progress

 

by  lim ju boo, alias lin ru wu (林 如 武)

When we examine the history of humanity, we are confronted by a remarkable paradox. Our ancestors lived much closer to nature, obtaining food from wild plants and animals, finding shelter in caves or simple dwellings, and depending directly upon the natural environment for survival. They possessed few material goods and had little of the technology that we now consider indispensable.

Today, modern humans inhabit a very different world. We live in houses and apartments, travel in motorcars and aeroplanes, communicate through smartphones, and depend upon sophisticated systems of agriculture, industry, transport, electricity, and healthcare. We have developed vaccines, antibiotics, surgical techniques, diagnostic instruments, and treatments for diseases that once caused widespread premature death.

These achievements have transformed human existence. In many countries, people can now expect to live considerably longer than their ancestors did a few centuries ago.

Yet a question remains: Has our progress made us healthier and happier, or have we exchanged the difficulties of primitive survival for a different collection of physical, psychological, social, and economic burdens?

We must be careful not to romanticize the past. Our ancestors faced hunger, injuries, infections, childbirth complications, and many dangers for which they had little effective protection. Nor should we dismiss the extraordinary benefits of modern science and medicine.

Nevertheless, it is worth asking whether our increasingly complicated way of life has introduced new problems that undermine some of the advantages we have gained.

Perhaps the most important distinction is between living longer and living better. They are related, but they are not identical.

The World of Our Hunter-Gatherer Ancestors

For most of human evolutionary history, our ancestors lived as hunter-gatherers. They obtained food by gathering edible plants, fruits, seeds, roots, nuts, and other naturally available resources, supplemented by hunting and fishing where circumstances permitted.

They did not depend upon modern supermarkets, industrial agriculture, processed foods, or global supply chains. Their survival required detailed knowledge of their surroundings, including seasonal changes, animal behaviour, edible plants, water sources, and the availability of shelter.

Daily physical activity was an unavoidable part of life. Depending on the environment and their way of life, people walked considerable distances, carried food, gathered fuel, prepared shelter, and performed other tasks necessary for survival.

Their diets varied greatly according to geography, season, and local ecology. Some communities consumed substantial amounts of animal foods, while others depended more heavily on plant foods. It would therefore be inaccurate to imagine that all prehistoric humans ate the same diet or enjoyed uniformly abundant natural food.

Their social lives were also different from ours. Many hunter-gatherer societies lived in relatively small communities, sharing practical knowledge and depending upon cooperation for survival. Their economic systems did not resemble modern economies built around wages, mortgages, commercial advertising, financial markets, and the continual purchase of manufactured goods.

However, life was not necessarily peaceful or stress-free. Food shortages, injuries, infections, conflicts, and environmental changes could threaten survival. Without effective antibiotics, modern surgery, or advanced obstetric care, an illness or injury that is manageable today could prove fatal.

The absence of industrial pollution and many modern consumer pressures may have offered certain advantages, but it did not protect our ancestors from the hazards of the natural world.

We should therefore regard hunter-gatherer life neither as an ideal paradise nor as a miserable existence. It was a different form of human adaptation, with its own advantages, limitations, and risks.

Did Ancient Humans Live Longer Than We Do Today?

This is one of the most important questions in our discussion.

It is tempting to suppose that because our ancestors lived closer to nature, ate less processed food, and engaged in more physical activity, they must have enjoyed longer lives. But the available demographic and archaeological evidence does not support the conclusion that prehistoric hunter-gatherers generally lived longer than modern humans.

The principal difficulty is understanding what scientists mean by life expectancy.

Life expectancy at birth is a statistical estimate based on the mortality rates experienced by people of different ages. If a population has high infant and childhood mortality, its life expectancy at birth can be very low, even when some individuals survive into their sixties or seventies.

Consider a hypothetical population in which many children die before reaching five years of age, while others survive to 65, 75, or beyond. Its average life expectancy at birth would be much lower than that of a population in which most children survive and adults have better chances of reaching old age.

This distinction is essential when comparing prehistoric populations with modern ones.

Historical records and demographic reconstructions show that life expectancy has increased dramatically over the past two centuries. Our World in Data reports that global life expectancy at birth was approximately 32 years in 1900, compared with about 71 years in 2021. The improvement resulted from reductions in mortality across several age groups, particularly among infants and children. [1]

These figures do not mean that every person in 1900 died at 32, nor that people today will necessarily die at the age represented by their country's current life expectancy.

They describe population-level mortality patterns, not the maximum biological lifespan of an individual.

Archaeological evidence can sometimes identify people who survived into older adulthood, but estimating the ages of ancient remains is difficult, and the surviving skeletons do not provide a complete census of the population. Consequently, claims that prehistoric people routinely lived longer than modern humans must be treated with caution.

A natural environment and a physically active lifestyle may have offered certain health advantages. Nevertheless, the absence of modern sanitation, effective infection control, emergency surgery, and reliable food supplies created substantial risks that could shorten life.

Adam, Methuselah, and the Biblical Perspective on Longevity

The question of human longevity also brings us to the biblical accounts of Adam and Methuselah.

According to Genesis 5, Adam lived for 930 years, while Methuselah lived for 969 years. These are the ages reported in the biblical narrative, and they have long attracted the attention of readers interested in the origins and duration of human life.

For believers, these accounts may carry theological significance concerning humanity's relationship with God, the history of creation, and the nature of life and death.

From the standpoint of modern science, however, we do not possess independent demographic evidence confirming that prehistoric human beings routinely lived for hundreds of years. The biblical ages cannot be treated as scientifically verified measurements of prehistoric longevity.

It is useful to distinguish the spiritual interpretation of a religious text from the methods used to establish biological and demographic facts. Respecting the significance of a biblical account does not require us to claim that science has independently verified every detail of it.

At the same time, the broader question raised by these accounts remains intellectually interesting: What determines how long a human being can live, and what conditions allow a person to approach the limits of human longevity?

Modern biology investigates this question through genetics, cellular processes, organ function, disease patterns, and the effects of nutrition and the environment. Although scientists have made considerable progress in understanding ageing, the mechanisms that determine the ultimate limits of human life remain incompletely understood.

The Great Transformation: From High Mortality to Longer Life

The most important transformation in human longevity did not arise from one medical discovery alone. It resulted from numerous improvements that gradually changed the conditions under which people were born, grew up, worked, and aged.

In earlier centuries, infectious diseases, contaminated drinking water, poor sanitation, malnutrition, and unsafe childbirth contributed heavily to premature mortality. Epidemics could devastate communities, while a lack of effective treatment made many otherwise manageable illnesses dangerous.

The development of public sanitation, safer water supplies, improved housing, better nutrition, vaccination, antibiotics, and modern obstetric care changed this situation profoundly.

Vaccines prevented many infectious diseases. Antibiotics made it possible to treat numerous bacterial infections that were once frequently fatal. Improved surgical techniques and anaesthesia expanded the range of conditions that could be treated. Blood transfusion, intensive care, diagnostic imaging, and laboratory investigations further increased the ability of healthcare professionals to recognize and manage serious illness.

These developments did not occur in isolation. Better agricultural productivity, improved transport, education, and economic development also helped people obtain food, maintain cleaner living environments, and access medical services.

The result was a major decline in premature mortality.

The World Health Organization estimates that global life expectancy at birth reached 73.3 years in 2023, approaching the pre-pandemic figure of 73.4 years recorded in 2019. This is a population average, and substantial differences remain between countries and communities. [2]

Modern civilization has therefore achieved something extraordinary: more people survive childhood, more adults reach old age, and many illnesses that once caused early death can now be prevented or treated.

We should not underestimate these accomplishments. Without them, the lives of many people living today would have been considerably shorter.

Mortality Rates: Why People Died Earlier in the Past

To understand the improvement in longevity, we must examine the causes of death.

In populations with high mortality, infectious diseases and nutritional deficiencies can claim lives at almost any age. Infants may die from infections, premature birth, or complications that modern medicine can often manage more effectively. Children may succumb to diarrhoeal diseases, pneumonia, or other infections. Adults may die from injuries, childbirth complications, or diseases for which effective treatments are unavailable.

Modern sanitation, vaccination, improved nutrition, and access to healthcare have substantially reduced many of these risks.

However, the pattern of mortality changes as populations become healthier and older. When fewer people die prematurely from infectious diseases, a larger proportion of the population survives long enough to develop age-related conditions such as cardiovascular disease, cancer, dementia, and other chronic disorders.

This does not mean that modern medicine has created these diseases simply by enabling people to live longer. Rather, survival into older age allows more time for chronic diseases and age-related biological changes to develop.

Modern populations consequently face a different balance of health challenges from those experienced by many earlier societies.

The objective of healthcare is not merely to postpone death from one disease until another appears. It is also to prevent illness, preserve functional ability, relieve suffering, and help people remain independent for as long as possible.

Life Expectancy Is Not the Same as Maximum Lifespan

Another important distinction is between life expectancy and maximum lifespan.

Life expectancy describes the average number of years a population can expect to live under specified mortality conditions. Maximum lifespan concerns the upper end of the ages reached by individual human beings.

A country can increase its life expectancy by reducing deaths among infants, children, young adults, and middle-aged people without necessarily changing the maximum age that any human being can attain.

Likewise, improvements in the survival of older adults can increase life expectancy even when the gains are smaller than those achieved through earlier reductions in childhood mortality.

Human ageing involves numerous biological processes, including changes in cellular function, the accumulation of molecular damage, alterations in immune function, and the gradual loss of resilience in tissues and organs. These processes interact in complicated ways.

Scientists are investigating whether future treatments can delay particular aspects of ageing, prevent age-related disease, or extend healthy life. But it would be premature to assume that human beings will soon live for 150, 200, or 1,000 years simply because biotechnology continues to advance.

The scientifically defensible objective is to extend healthy life while reducing preventable disease and disability. Whether maximum human lifespan can be substantially increased remains an open question.

Have We Become Healthier, or Merely Better at Treating Disease?

Modern medicine has greatly improved the ability to prevent and treat illness. Nevertheless, the existence of advanced medical technology does not automatically mean that every aspect of modern life promotes health.

Many contemporary societies face substantial burdens from cardiovascular disease, diabetes, obesity, certain cancers, and other chronic conditions. Their causes vary, and it would be simplistic to attribute them all to modern lifestyles. Ageing populations, genetics, socioeconomic circumstances, environmental exposures, and access to preventive care also influence these diseases.

Still, certain modifiable factors deserve attention.

Physical inactivity can contribute to poor metabolic health. Diets that are excessively energy-dense and nutritionally unbalanced can increase the risk of obesity and related diseases. Smoking, excessive alcohol consumption, inadequate sleep, and persistent stress can further undermine health.

Conversely, regular physical activity, a balanced diet, sufficient sleep, avoidance of tobacco, and effective management of established risk factors can help preserve health.

The lesson is not that ancient life was necessarily healthier, but that modern societies sometimes neglect basic biological requirements while investing heavily in treating the consequences.

A sophisticated hospital is essential when a person becomes seriously ill. Yet preventing disease through good living conditions, healthy behaviours, vaccination, and timely medical care can be equally important.

The best approach combines prevention with effective treatment rather than treating them as competing alternatives.

The Hidden Cost of Modern Social and Economic Life

Our ancestors faced immediate challenges associated with survival. Modern people face these challenges too, but many also experience pressures arising from complex economic and social systems.

Housing costs, mortgages, employment insecurity, financial commitments, educational competition, caregiving responsibilities, and the expectation of maintaining a particular standard of living can produce persistent stress.

Technology has made communication faster, but it has also made many people continually reachable. Work messages may arrive outside normal working hours, while social media can encourage constant comparison with the achievements, possessions, and lifestyles of others.

The result may be a sense that one must continually work harder, earn more, acquire more, and accomplish more simply to avoid falling behind.

Not everyone experiences these pressures in the same way. Modern employment can provide purpose, companionship, financial independence, and personal fulfilment. Economic development can improve health by providing better housing, food security, education, and healthcare.

The problem arises when the demands of work and consumption become excessive relative to a person's physical and psychological resources.

The World Health Organization and International Labour Organization reported that working at least 55 hours per week was associated with an increased risk of ischaemic heart disease and stroke compared with working 35–40 hours per week. Their analysis estimated that long working hours were attributable to approximately 745,000 deaths from these two conditions worldwide in 2016. [3]

These findings do not prove that every form of work-related stress causes disease, nor that all modern workers are exposed to dangerous conditions. They do, however, demonstrate that economic activity can carry measurable health costs when working hours become excessive.

A society that increases production while damaging the health of its workforce must ask whether it is achieving genuine progress.

Economic activity should support human well-being, not consume so much of people's time and energy that they have little opportunity to enjoy the lives they are working to sustain.

The Biological Needs of Life Versus the Material Desires of Humanity

This brings us to one of the central observations behind our discussion.

Every living organism requires suitable conditions for survival. Animals need food, water, energy, and a habitat appropriate to their biology. Plants require light, water, nutrients, and suitable environmental conditions. Microorganisms also depend upon particular combinations of nutrients and physical conditions.

Human beings share these fundamental biological requirements.

Yet human civilization has developed an enormous range of activities and desires that extend far beyond immediate biological necessity. We manufacture luxury goods, replace functional products with newer models, build increasingly elaborate structures, and consume resources for entertainment, prestige, convenience, and competition.

There is nothing inherently wrong with enjoying art, music, comfortable housing, technology, or other products of human creativity. Such activities can enrich life and provide genuine benefits.

The difficulty arises when the pursuit of material goods becomes excessive, wasteful, or environmentally destructive.

A person does not need the latest smartphone to maintain cellular health. A family does not require an unnecessarily large house to obtain adequate shelter. Society does not benefit when usable goods are discarded merely because they are no longer fashionable.

The distinction is between material activities that genuinely support human welfare and those whose benefits are too small to justify their environmental and social costs.

Moreover, human needs are not purely biological. We also need affection, companionship, intellectual stimulation, cultural expression, and a sense of belonging. These are important aspects of human well-being, even though they cannot be reduced to food, water, and shelter alone.

A mature civilization would therefore seek to meet both our biological and social needs while reducing unnecessary material consumption.

The Environment: When Modern Comforts Undermine Future Health

Modern civilization depends upon vast quantities of energy, water, minerals, land, and manufactured materials. These resources support hospitals, transport systems, agriculture, housing, communications, and industry.

But extracting and processing resources can generate pollution, destroy habitats, and contribute to climate change. Industrial and agricultural waste can contaminate ecosystems, while excessive consumption increases the demand for new materials and energy.

Environmental deterioration can eventually return to affect human health through contaminated air and water, heat exposure, food insecurity, infectious disease risks, and damage to essential infrastructure.

This creates a paradox. The same civilization that has developed sophisticated medical treatments may undermine some of the environmental conditions necessary for good health.

It is not necessary to reject modern technology to address this problem. Cleaner energy, more efficient transport, sustainable agriculture, pollution control, resource recovery, and better urban planning can reduce many environmental harms.

The goal should be to preserve the genuine benefits of civilization without assuming that every increase in production or consumption represents progress.

Human health cannot be separated entirely from the health of the ecosystems upon which food production, water supplies, and stable living conditions depend.

Can We Live Longer by Living More Simply?

A simpler life cannot guarantee longevity, and there is no sound basis for claiming that returning to a prehistoric lifestyle would make modern humans live longer. Nevertheless, certain elements of a less stressful and less consumption-driven life could improve health.

Regular movement, nutritious food, sufficient rest, meaningful relationships, time outdoors, and a reasonable balance between work and leisure are compatible with modern scientific understanding of health.

Reducing unnecessary financial commitments and resisting excessive consumer pressure may also improve quality of life for some people. However, individual circumstances differ, and stress cannot always be eliminated through personal choices alone. Employment conditions, housing affordability, caregiving demands, and access to social support may require wider institutional solutions.

A healthier society would not ask every individual to solve structural problems through willpower. It would also create environments in which healthy choices are practical and affordable.

For example, cities could provide safe walking paths and accessible public transport. Employers could respect reasonable working hours. Schools could teach nutrition and physical activity. Governments could protect clean water, control pollution, and support effective preventive healthcare.

Such changes would not take us backwards. They would use the achievements of modern civilization to create conditions more compatible with human biology.

Perhaps the objective should be to retain the knowledge and benefits of civilization while discarding its unnecessary burdens.

The Meaning of a Longer Life

Even if future medical discoveries enable more people to live beyond 90 or 100 years, we must still ask what those additional years will be like.

A longer life spent in good health, with independence, meaningful relationships, and opportunities for learning, can be a wonderful achievement. A longer life dominated by severe illness, pain, disability, or social isolation presents a different challenge.

This is why healthy life expectancy is an important complement to ordinary life expectancy.

According to the World Health Organization, global healthy life expectancy at birth was estimated at 62.8 years in 2023, compared with overall life expectancy of 73.3 years. These measures describe different aspects of population health; they do not mean that every person becomes unhealthy at 62.8 years. [2]

The difference reminds us that living longer and living in full health are not the same thing.

Medicine should continue to seek better treatments, prevent disease, and relieve suffering. At the same time, societies should consider how to improve the quality of the years people live, rather than concentrating exclusively on extending their number.

Human life has value beyond its economic productivity. Older people should not be regarded merely as retired workers, and younger people should not be valued only for their future earning capacity.

A humane civilization recognizes the dignity of people at every stage of life.

Progress Should Serve Life, Not the Other Way Around

From our hunter-gatherer ancestors to modern civilization, humanity has undergone an extraordinary transformation. We have developed agriculture, cities, industry, science, and medicine. We have reduced many causes of premature death and enabled far more people to reach old age.

These achievements should be celebrated rather than dismissed.

Yet the story is incomplete if we measure progress only through technological sophistication, economic output, or the number of years people live.

Our ancestors faced the harsh realities of natural survival. Modern humans have gained protection from many of those dangers, but we have also created new pressures through complex economies, excessive consumption, environmental degradation, and the constant pursuit of material advancement.

The answer is not to return to caves or abandon scientific medicine. It is to recognize that the benefits of civilization should support the needs of life rather than create an endless cycle of production, consumption, and dissatisfaction.

We need food, water, shelter, healthcare, education, companionship, and opportunities to live meaningfully. We can enjoy art, music, science, technology, and other expressions of human creativity without treating unlimited material accumulation as the purpose of existence.

Perhaps the true measure of progress is not how many possessions we acquire, how much wealth we accumulate, or even how many years we add to our lives. It is how successfully we preserve health, dignity, relationships, and the natural environment while reducing avoidable suffering.

The future of longevity will depend partly upon scientific discoveries, but also upon the social and environmental conditions in which people live. Medical science may help us survive diseases that once killed us prematurely, yet a healthy society must also protect the conditions that allow people to flourish.

Our ancestors lived in a world that imposed limits upon their material ambitions. Modern humanity possesses the power to overcome many natural limitations, but that power does not exempt us from biological realities or ecological constraints.

Perhaps the next stage of civilization requires a different kind of wisdom: the ability to distinguish what we can acquire from what we truly need, what we can produce from what we ought to produce, and what makes life longer from what makes life worth living.

We cannot turn back the clock of civilization, but we can learn to live more wisely within it. The greatest achievement may not be to prolong life indefinitely, but to make the years we have healthier, more meaningful, and more harmonious with the living world that sustains us.

References

 

1. Dattani, S., Rodés-Guirao, L., Ritchie, H., Ortiz-Ospina, E., & Roser, M. Life Expectancy. Our World in Data. Historical trends and explanations of changes in global life expectancy. https://ourworldindata.org/life-expectancy

2. World Health Organization. Life Expectancy and Healthy Life Expectancy. Global Health Observatory. Global estimates and definitions of life expectancy and healthy life expectancy. https://www.who.int/data/gho/data/themes/mortality-and-global-health-estimates/ghe-life-expectancy-and-healthy-life-expectancy

3. Pega, F., Náfrádi, B., Momen, N. C., et al. (2021). Global, regional, and national burdens of ischemic heart disease and stroke attributable to exposure to long working hours for 194 countries, 2000–2016: A systematic analysis from the WHO/ILO Joint Estimates of the Work-related Burden of Disease and Injury. Environment International, 154, 106595. https://doi.org/10.1016/j.envint.2021.106595

4. World Health Organization. Global Health Estimates. Mortality, life expectancy, and disease burden data by country, age, sex, and cause. https://www.who.int/data/global-health-estimates

5. World Health Organization & International Labour Organization. (2021). Long working hours can increase deaths from heart disease and stroke. https://www.who.int/news/item/17-05-2021-long-working-hours-increasing-deaths-from-heart-disease-and-stroke-who-ilo