Stephen Boyden

Contents:
Biological background

The evolutionary health principle
Universal health needs - physical
Universal health needs - psychosocial

Impacts of civilisation – past and present

Air pollution
Population growth
Tobacco smoking
Viral and bacterial diseases
Cardiovascular diseases and cancer
Mental health
Health disparities
Consumerism

The future

Human health needs
Equity
Health of the biosphere

Biological background

One of the natural outcomes of the processes of evolution is the fact that animals become well adapted in their biological characteristics to the habitat in which they are evolving. This is because evolution selects for characteristics – structural, physiological and behavioural – which tend to increase the likelihood that individual specimens will perform optimally in that environment, will overcome its hazards and will survive long enough to reproduce. In other words, the biological characteristics of any species are such that the individual animals are likely to experience good health in their natural environment.

The evolutionary health principle - If an animal is removed from its natural environment, or if its environment changes significantly, then it is likely to be less well adapted to the new conditions, and consequently some signs of physiological or behavioural maladjustment can be expected. This is a fundamental biological principle, here called the evolutionary health principle.

It follows from this principle that if we want to identify the health needs of any particular kind of animal, the first thing to do is to study the conditions to which it is exposed in its natural habitat, because we can be sure that these conditions are capable of providing all the essential ingredients for maintaining and promoting health in that species.

In the case of humankind, our basic biologically determined health needs are the same now as they were many thousands of years ago. Biologically, we are the same animal as our pre-farming forebears of, say, 10 000-20 000 years ago – that is, an animal adapted genetically, through evolution, to the hunter-gatherer conditions of life. There have certainly not been a sufficient number of generations of people living in cities to produce a new breed of humanity better adapted genetically than our hunter-gatherer ancestors to urban life.

There are countless examples of ill-health in humans resulting from exposure to conditions deviating significantly from those prevailing in the natural habitat of the species.

Universal health needs – physical

The evolutionary health principle clearly applies to a wide range of physical aspects of life conditions in humans. There is no diet better for us than that which was typical for hunter-gatherers, and noise levels much higher or much lower than those typical of the primeval environment are likely to be deleterious for health. It is also clear that the principle is applicable to some aspects of behaviour. For example, health is likely to be impaired if levels and patterns of physical exercise deviate significantly from those of humans in the natural habitat.

Applying the evolutionary health principle and taking our knowledge of the conditions of life of hunter-gatherers as a starting point, we can put together a working list of the physical conditions likely to promote health and well-being in our species (Box 1). We refer to them as universal health needs, because they apply to all members of the human species wherever or whenever they may be living.

Universal health needs - psychosocial

There are good reasons for supposing that the evolutionary health principle also applies to relatively intangible aspects of life experience. The life conditions of hunter-gatherers are usually characterised, for example, by incentives and opportunities for creative behaviour, a sense of personal involvement in daily activities and a good deal of convivial social interaction. Most of us would agree that such conditions are all likely to promote health and well-being in our own society. It is important that we take them into account in assessing the quality of life in our own society today and in considering options for the future^[1].

A list of postulated psychosocial determinants of health based on this evolutionary approach is presented in Box 2.

This list is not definitive, and other people would use different terms to describe these aspects of experience, or they might add further items that they consider important. But all the items listed here were characteristic of the life conditions of our ancestors in the natural habitat of the human species, and are therefore at least compatible with optimum performance.

A case in point is a sense of personal involvement and purpose in daily activities, linked with a sense of belonging to a community. Certainly, this kind of experience was built into the hunter-gatherer life style and was shared by all adults. It was also experienced by adolescents, who felt personally involved as they learned the skills of adults and attempted to prove their worth in the daily affairs of the band to which they belonged.

It is true that not every item listed is absolutely essential for health. Lack of satisfaction of one psychosocial health need may be offset to some extent by the satisfaction of others. Nevertheless, it is suggested that every item on the list will, if satisfied, make a positive contribution to health and well-being.

Brief comment is called for on the concept of stressors and meliors. Stressors – that is, experiences which cause anxiety and distress – are a normal aspect of life. If they are short-lived and not too severe, they can contribute positively to the quality of life and well-being. But if they are excessive, and if they persist, they may interfere with both mental and physical health.

Equally important as influences on human well-being are experiences that have the opposite effect to stressors and that give rise to a sense of enjoyment. Such experiences have been called meliors. Meliors may include, for example, the experience of creativity, fun, aesthetic enjoyment, affection or conviviality.

Every person can be considered, at any given time, to be at some point on a hypothetical continuum between a state of distress and a state of enjoyment. An individual’s position on this continuum is largely a function of the balance between meliors and stressors in his or her recent experience. Social changes that result in the erosion of meliors are therefore just as undesirable as those that result in an increase in stressors.

The cultural environment has an immense influence both on the levels of meliors and stressors in an individual's daily experience as well as on the nature of the factors that cause them. It also affects the energy and pollution costs of attempts to avoid stressors or to experience meliors.

Impacts of civilisation – past and present

Over the ages, human culture, through its effects on the biophysical environment and on people’s behaviour, has had major impacts on human health. Some of these impacts can be regarded as positive. For instance, the farming way of life offered protection from predators and less chance of serious injury in hunting.

On the other hand, civilisation resulted in humans being exposed to new conditions which differed significantly from those to which the species was adapted through evolution. In accord with the evolutionary health principle, some of these changes gave rise to serious forms of maladjustment. The most notable of these diseases of early civilisation were malnutrition due to specific dietary deficiencies, like rickets, scurvy, beri beri and pellagra, and a range of contagious diseases including typhus, typhoid, plague, cholera and smallpox^[2].

Air pollution - Sometimes cultural developments have resulted in interference with the universal health need for clean air. A good example is provided by the history of air pollution in London resulting mainly from the burning of coal. Serious concern had been expressed about this problem from the beginning of the fourteenth century. It is only in the last half century that cultural reforms have brought about a significant improvement in the situation, with major benefits for the health of Londoners. Air pollution is still a very serious problem in many cities, especially in the developing world. (More about air pollution)

Population growth - Thus civilisation, while affording some protection against primeval causes of ill health and death, introduced new diseases which were responsible for very high death rates in many early urban environments. The populations of these societies were probably maintained by continuing immigration from rural areas, where by far the greater part of the total human population lived and where death rates are likely to have been lower. The end result was an overall increase in the total human population from around 5 to 10 million when farming was first introduced to about 600 million in 1700 AD. This is a doubling time, on average, of between 1500 and 2000 years.

The spectacular drop in the incidence of the serious infectious diseases and malnutrition in the past century or so, especially in the developed countries, has been due to extraordinarily effective cultural reform directed at these causes of ill health. The following factors have been especially important: improved sanitation; improved nutrition following improved understanding of human dietary requirements; immunisation programs; and the introduction of antibiotics.

As a consequence of the protection that modern civilisation now provides against both the hazards of the primeval lifestyle and the diseases of early civilisation, death rates have been drastically lowered, especially in the developed countries, and life expectancy at birth is higher than ever before. As a result, the doubling time of the total human population in the last part of the twentieth century was around 35 years. (More about human population growth)

Viral diseases - Although there has been a spectacular drop in the incidence of serious bacterial disease, modern populations are exposed to an ever-increasing number of pathogenic viruses that cause relatively mild diseases like the common cold, influenza and various gastro-intestinal disturbances. Although these infections are seldom fatal, they nonetheless interfere with people's enjoyment of life. These are relatively new diseases, because they can only exist if there is a large contiguous human population to keep them going. They could not have survived in hunter-gatherer times, nor probably throughout most of early civilisation.

Much more serious has been the advent of Acquired Immune Deficiency Syndrome (AIDS) due to infection with HIV. While this disease is not a major cause of death in Australia, over three million died of AIDS world-wide in 2003.

With respect to bacterial disease, a serious cause for concern at the present time is the emergence of antibiotic resistant strains of disease-causing bacteria (e.g. certain strains of Staphylococcus aureus). (More about viral and bacterial diseases)

Tobacco smoking - A conspicuous deviation from natural conditions in today’s society is the deliberate inhalation of smoke from burning leaves of the tobacco plant. Since Europeans first picked up this habit from native Americans in the sixteenth century, the practice has spread to all parts of the world.

Tobacco smoking causes cancers of the lung, lip, nasal cavities, pharynx, larynx, pancreas and bladder. About a third of all cancer deaths and 80 per cent of cases of lung cancer are due to smoking. Smoking also doubles the risk of heart attack, and is responsible for around 40 per cent of strokes in people under forty. Almost all smokers develop some form of emphysema, the severity of which is proportional to the number of cigarettes smoked each day and the number of years a person has smoked. Three quarters of cases of chronic bronchitis are due to smoking; and smoking increases, by about ten times, the risk of gangrene due to narrowing of the leg arteries. On average, smokers die 6 years younger than non-smokers. Between a third and a half of all smokers end up dying from cancer or heart disease caused by their addiction.

Whereas in most countries in the developed world the majority of adults do not smoke, cigarette sales are at present booming throughout Asia and the former Soviet bloc. In Japan, for example, 60 per cent of the men are smokers. Globally, cigarette smoking is increasing by 1 per cent a year. There are now about 1.1 billion smokers in the world, and the number is expected to increase to 1.6 billion by 2025. It is estimated that by 2020 more people will be killed by tobacco than by any other cause of death.

Although the psychological effect of nicotine is less dramatic than drugs like heroin and cocaine, its addictive power is at least as great.

Cardiovascular disease and cancer - The two leading causes of death in our society today are cancer and cardiovascular disease; yet many cases of both are preventable.

Cardiovascular disease is largely a response to unnatural lifestyle factors. The main detrimental influences are tobacco smoking, lack of physical activity, overeating, a high intake of certain saturated fats and a low intake of certain polyunsaturated fats in the diet.

Many cases of cancer are also the result of people’s behaviour patterns, including, of course, tobacco smoking. Lack of plant fibre in the diet contributes to cancer of the colon, and high intake of certain fats in the diet increases the likelihood of breast cancer. Overeating is also believed to contribute to the incidence of cancer. Environmental pollutants are another important cause^[3].

Mental health - According to the World Health Organisation, mental illness now accounts for almost eleven per cent of the total ‘disease burden’ world-wide.

It is difficult to pinpoint the causes of mental illness, although it seems very likely that it is often a response to lack of satisfaction of the universal psychosocial health needs of the human species. Certainly, there have been major changes in the quality of life in Western countries, including Australia, over the past half century. If the number of hours sitting in front of a television screen is taken as a measure of well-being, then undoubtedly the population is vastly better off than it was, say, half a century ago. We would come to a similar conclusion if we took the per capita rate of use of material resources as our measure of the good life, or the number of kilometres travelled in fast-moving vehicles.

On the other hand, what would our answer to this question be if we took the indicators of well-being to be such aspects of life experience as creativity, sense of personal involvement and purpose, experience of conviviality, warm relationships with members of the extended family, contemplation of the natural beauty of the wilderness, and absence of fear of robbery or violence?

Certainly, cultural changes since the urban transition, and especially in the high-consumption societies, have had a profound effect on people’s psychosocial life experience. Especially important is the fact that many adolescents in the modern setting experience little sense of personal involvement and purpose in their daily lives, sometimes with serious consequences for themselves or for other members of society.

One of the outstanding characteristics of contemporary urban civilisation, as contrasted with primeval society, is the enormous variation within populations in these psychosocial aspects of life experience. Some occupations are associated with hour after hour of repetitive, tedious and boring activity, while others provide plenty of variety, challenge and enjoyment. The experience of conviviality is also much more evident in some subcultures than in others. Similarly, some people are part of rich mutual support networks, while others are very much out on their own. Sheer soul-destroying loneliness is commonplace in modern urban society.

Because these less tangible aspects of life experience, unlike diet, air quality, noise levels and income, cannot be easily measured or assessed in a scientifically satisfactory way, and because we are not practised at talking about them, there is a real risk that cultural changes might bring about their progressive erosion without eliciting any social response aimed at preserving or restoring them. They are not taken into account in our society’s conventional measures of social well-being, and they do not feature on the platforms of the major political parties. (More about quality of life)

Consumerism - Consumerism is an outstanding characteristic of life in the developed countries of the modern world. The current economic arrangements mean that high levels of employment are dependent on high rates of consumer spending, and the economy is judged to be healthy when consumer spending is high. This fact has important ecological implications, because most consumer spending is on goods or services that involve the use of material resources and energy and the production of technological waste products. In fact, present patterns of consumerism in the affluent countries are simply not ecologically sustainable in the long term.

Whereas humans can, of course, experience health and a high quality of life without high levels of acquisition of material goods, it seems that in our present cultural setting most people have become dependant on consumerism for their well-being. Over the past couple of generations selecting and purchasing manufactured goods has become an important source of enjoyment, countering the undesirable effects of boredom and other environmental stressors. A common and often effective response to a feeling of depression is a shopping spree; and the human tendencies to seek approval, attention, status and novelty all lead to active consumer behaviour.

Perhaps consumer behaviour is now compensating for the decline of various meliors that were characteristic of earlier societies and that cost little energy and material resources – such as creative behaviour, the experience of conviviality, a sense of personal involvement and singing and dancing. The forthcoming inevitable collapse of consumerism will need to be accompanied by the re-introduction of these ancient sources of enjoyment.

According to recent studies in the United States, per capita consumption has increased by 45 per cent over the past twenty years. However, during the same period of time the quality of life, as measured by the ‘Index of Social Health’, decreased by 51 per cent. Our material standard of living here in Australia, as reflected in figures for energy use, is now more than twice what it was in 1965: but is there any evidence that people are enjoying life any more now than they were over 40 years ago?

From the ecological standpoint, it is significant that in the modern cultural setting the following basic behaviours usually cost significantly more energy, and create more pollution, than they did at other times in history: seeking in-group approval; seeking to conform; seeking attention; seeking novelty, excitement and variety; seeking comfort; visiting relatives; being selfish; being greedy; and being generous.

Health disparities - One of the outstanding features of modern civilisation is the fact that, unlike primeval and early farming societies, there are gross disparities in the health status of different parts of the human population. To mention just one example, the rate of mortality in childbirth in Somalia is 1 in 7, compared with 1 in 5100 in the United Kingdom.

Disparities also exist within nations. In Australia in the period 1991 to 1996, for example, there were about three times as many deaths among indigenous people as there would have been if this population had the same death rates as the total Australian population. Life expectancy at birth for indigenous Australians was estimated to be 56.9 years for males and 61.7 years for females, as compared with the all-Australian estimate of 75.2 years for men and 81.1 years for females^[4].

The future

Looking to the future, three points need emphasis.

Human health needs - First, people’s conditions of life and lifestyles must be in tune with human nature. That is, they must satisfy the innate biologically determined health needs of the human species. They must satisfy not only physical health needs, such as good, uncontaminated food, clean air, clean water and adequate shelter, but also psychosocial needs, like opportunities and incentives for creative behaviour, an aesthetically pleasing environment, the experience of conviviality and a sense of personal involvement in daily activities. It is likely, and certainly desirable, that the new biosensitive society will, in scaling down consumption of resources and use of energy, put a great deal more emphasis than it does at present on these psychosocial health needs, including the need for a sense of meaningful challenge to be built into people’s life experience, especially in the younger generation.

Equity - Second, unlike the situation today, the physical and psychosocial health needs must be satisfied in all sections of society, and in all ethnic and racial groups.

Health of the biosphere - The third point is that these health needs of the human population must be met in ways that are consistent with the satisfaction of the health needs of the biosphere. This means that lifestyles must be in keeping with major reductions in the use of energy and material resources across society, and they must not involve activities that directly or indirectly cause significant chemical pollution, land degradation or loss of biodiversity. Fortunately, we know that humans are perfectly capable of living healthy and enjoyable lives in communities with vastly lower rates of material consumption than those of our current society.

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1. For further discussion on psychosocial health needs see Quality of life

2. For further discussion see Infectious diseases.

3. For a more detailed discussion of the causes of ill health in present-day society see Diseases of modern civilisation and Quality of life.

4. For further discussion on disparities in human conditions of life see Climate change and human health.

For the first part of his career Stephen Boyden, whose first degree was in Veterinary Science (London, 1947), carried out research in immunology in Europe and America - and eventually in Australia at the Australian National University (ANU). In the mid-sixties, to the consternation of some friends and colleagues, he changed direction, to work on human ecology and biohistory, also at ANU. He has been associated with the Nature and Society Forum since its inception in 1991.

This paper as a 127KB PDF

Contents
Enhanced greenhouse effect
Thinning of the ozone layer
Soil erosion
Soil salinity
Disruption of natural nutrient cycles
Loss of biodiversity
Persistent organic pollutants (POPs)

This paper contains brief summaries of the most important ecological issues in Australia at the present time. It also contains a diagram summarising the cause-and-effect chains that link undesirable changes in living systems with the human activities that cause them. In some cases the chain is short and direct (e.g. the impact of logging on the trees of forests), while in others it is complex and indirect (e.g. the likely impacts of releasing CFCs into the environment).

Enhanced greenhouse effect

The concentration of carbon dioxide in the atmosphere is increasing globally as the result of human activities, mainly as the result of the combustion of fossil fuels as a source of energy.

While there is still uncertainty about the precise consequences of this change, the majority of atmospheric scientists predict that, together with the release of other greenhouse gases (e.g. methane and halons), it will lead to progressive climate change, causing major disturbances in global ecology, with wide-ranging consequences for humankind. Most atmospheric scientists are of the opinion that global warming resulting from the release of greenhouse gases is already underway.

Thinning of the ozone layer

In recent decades there has occurred a steady accumulation of chlorofluorocarbons (CFCs), methyl bromide and halons in the atmosphere. CFCs are synthesised chemical compounds used in refrigerators, and methyl bromide is used as a biocide for the control of insect pests in the soil and in grain products. The main source of the halons is fire extinguishers.

These gases are causing the progressive destruction of the ozone layer in the upper atmosphere. Certain waste products of high flying aircraft also contribute to the destruction of the ozone layer.

Because the ozone layer acts as a filter, shielding the surface of the Earth from ultraviolet radiation from the Sun, the thinning of this layer is resulting in an increase in the intensity of UV radiation reaching the Earth’s surface. This is likely to have an increasingly damaging effect on terrestrial organisms, with serious consequences for the natural environment and for humankind. The shorter wave UV-B rays are especially harmful. It is predicted, for example, that the yields of soya beans, peas and beans will decrease by a quarter when UV-B radiation increases by 25%. Increased UV radiation is also likely to destroy the phytoplankton at the surface layers of the oceans. Because phytoplankton are at the base of the oceanic food chain, this change would have a devastating impact on populations of fish and other animal life in and around the sea.

Research suggests that the incidence of skin tumours in humans increases by about 5% for every 1% decrease in stratospheric ozone.

As a result of international agreements, there has been a major reduction in the release of CFCs and related compounds, and it is now hoped that the ozone layer will be back to normal by around 2065. However, this will depend on the extent to which the current black market in halons and CFCs in developing regions of the world is brought under control.

Soil erosion

Soil loss resulting from wind or water erosion is a major ecological problem in many parts of the world today, especially in Australia. It is largely the consequence of land being denuded of a protective cover of vegetation as a result of over-stocking with cattle or sheep or the widespread use of the plough and other cultivation implements in areas with shallow topsoil. It can also come about as a result of disruption of the soil surface in the construction of roads and buildings.

Soil erosion leads to greatly reduced bioproduction and reduced biodiversity. In Australia the wheat and sheep areas of New South Wales, for example, are subject to serious soil erosion.

Soil salinity

Salt is a natural component of soils and water, but certain human activities have increased the salinity of soils in many areas. There are two main forms of human-induced salinity in rural parts of Australia. They are dryland salinity and irrigation salinity.

According to the prevailing view, dryland salinity is due to the clearing of native vegetation, with the result that rainwater seeps down through the soil to the groundwater. This leads to a raising of the level of the water table. Because the ground water has a high salt content, this leads to an increase in salt concentration at or near the soil surface. Before land clearance native trees, shrubs and perennial grasses effectively dried out the soil to the depth of root penetration.

Another school of thought holds that the underlying cause of much dryland salinity is a decline in soil structure due to the loss of organic matter – resulting in particular from the disappearance of native perennial grasses. This results in increased lateral flows of water in the soil and a decrease in deep percolation, leading, in turn, to the accumulation of water in low areas, where evaporation results in increased concentration of salt. According to this hypothesis the effect is not due to a rising water table. (This hypothesis is not represented in the diagram below).

Irrigation salinity occurs when water that is added for irrigation is not used by crops and vegetation. It seeps through to the water table, raising its level and so leading to soil salinity. Basically it is caused by over-irrigation.

Salinisation of soils and streams is a regional problem and is especially serious in the irrigation areas along the Murrumbidgee and Murray Rivers. Dryland salinity, as distinct from irrigation salinity, occurs across much of the south-west of Western Australia, where 250 km2 of agricultural land is lost each year due to soil salinity resulting from over clearing of native vegetation.

Salinisation of soils leads to serious reduction of bioproductivity. There is commonly a time lag of some decades between the clearing of vegetation and the impacts of salinisation.

Disruption of natural nutrient cycles

In natural ecosystems there is continual recycling of nutrients involved in the processes of life, and the continued bioproductivity of these systems is dependent on this cycling process.

Human activities can interfere with natural nutrient cycles by extracting nutrients from farmland in the form of food, and eventually disposing of them in organic waste which is not returned to the farmland. Consequently, there is a progressive loss of key nutrients from food producing ecosystems. Serious soil erosion resulting from poor farming practice can also lead to permanent loss of nutrients.

At present, this problem is largely overcome by replacing the extracted nutrients with artificial fertilisers, like phosphorus and nitrogen from other sources. This, in turn, often builds up a high level of acidity in soils, which then requires neutralisation with lime. There are serious doubts about the long-term sustainability of these practices.

Loss of biodiversity

The present rate of extinction of living organisms is exceptionally high, due to the activities of humankind. According to one estimate, species are becoming extinct at a rate about 1000 times higher than was the case in the late Pleistocene epoch, when the extinction rate was well above the average for geological time as a whole.

There are believed to be some 5 to 7 million species of animals, plants, fungi and micro-organisms (excluding bacteria and viruses) on Earth. Some authorities believe that about a quarter of these will be extinct by around 2025. Nearly 9000 kinds of trees, representing around 10% of the species known to science, are threatened with extinction. Over 34 000 species of plants face extinction. Among animals, mammals are now recognised to be much more endangered than birds.

The main cause of this loss of biodiversity on land is habitat destruction through various bioharvesting activities of humankind, including farming and logging. Other causes include the release of feral species into the environment and construction of buildings and roads. Serious and progressive loss of biodiversity in the oceans is the result of the increasing and unsustainable scale of the fishing industry.

Persistent organic pollutants (POPs)

These are compounds which are used as pesticides and in various technological processes, and which are being released into the environment in large quantities, and accumulating in soils, lakes and in the oceans. They include DDT, PCBs, chlorinated furans, Dioxins, Aldrin, Dieldrin, Endrin, Chlordane, Hexachlorobenzene, Mirex, Toxaphene, Polybrominated biphenyls (PBBs) and Polybrominated diphenyl ethers (PBDs), as well as oestrogen-like compounds, such as bisphenol used in white tooth fillings and for lining tin cans, and 4-octyphenol used in detergents, pesticides, herbicides.

POPs accumulate in the tissues of living organisms, and they are believed to be responsible for widespread and increasing infertility in wild animals, and probably also in humans. They are also suspected of contributing to the increase in breast cancer in women and to reduced sperm counts in men.

Water supply

The ecological sustainability of any community is dependent on an adequate and reliable supply of clean water. The rate of use of water in many Australian cities and townships is unnecessarily high, and serious water shortages are likely in the future. It is clear that more effective measures must be introduced to reduce the rate of consumption. These will include steps to minimise wastage of water, and recycling of grey water for purposes other than drinking. Over the past fifty years Australian water supply authorities have had to use an increasing number filters, chemicals and treatments to counter the deteriorating quality of water from reservoirs.

Conclusions

This overview has summarised the major human-induced ecological issues encountered in Australia at the present time – ranging from local causes for concern through to some issues of global significance.

The causes of the current ecological unsustainability of human societies across the world, including Australia, need also to be considered at a more general level. It is clear, for example, that a major factor is the sheer scale of human activities and their impacts. There are two underlying causes of this:

1. The number of humans now living on our planet - There are now about 1000 times as many people on Earth as there were when some of our ancestors started farming, around 450 generations ago. Most of the increase in population has occurred since the beginning of the industrial transition, some eight generations ago. Since that time over 5000 million people have been added to the global human population, bringing the present total to well over 6000 million. This change inevitably means a colossal impact on agricultural ecosystems.
2. Changes in patterns of human activity - A major trend with widespread ecological repercussions has been the massive intensification of industrial activities over the past few generations, involving enormous increases in the rate of use of resources and energy and production of technological wastes. This change has so far mainly occurred in the developed nations and is associated with intense consumerism and increase in material standard of living. The amount of carbon dioxide produced by the human population every day, for example, is about 12 000 times what it was when farming began. One tenth of this increase is directly the result of the growth in population, while the rest is due mainly to the use of fossil fuels in manufacturing, transportation and the production of electricity.

Prospects - What, then, are our prospects for the future? On the one hand we have witnessed an extraordinary growth in environmental awareness over the past few decades, and most people have at least heard of most of the ecological issues discussed in this pamphlet. And here and there some specific action is being taken aimed at improving the situation. On the other hand, these responses have not been sufficient to have any significant impact on the overall picture. Many of the ecological problems, especially the regional and global ones, continue to worsen.

The Millennium Ecosystem Assessment (MA) - An important report relevant to these considerations was published in March 2005. It had been called for by United Nations Secretary-General in 2000. It involved the work of 1360 experts around the world.

The following excerpts from the statement from the Board governing the MA process summarise some of its conclusions.

At the heart of this assessment is a stark warning. Human activity is putting such a strain on the natural functions of Earth that the ability of the planet’s ecosystems to sustain future generations can no longer be taken for granted.

The provision of food, fresh water, energy and materials to a growing population has come at considerable cost to the complex systems of plants, animals, and biological processes that make the planet habitable.

As human demands increase in coming decades, these systems will face even greater pressures – and the risk of further weakening the natural infrastructure on which all societies depend.

Protecting and improving our future well-being requires wiser and less destructive use of natural assets. This in turn involves major changes in the way we make and implement decisions.

We must learn to recognise the true value of nature – both in an economic sense and in the richness it provides to our lives in ways much more difficult to put numbers on.

Above all, protection of these assets can no longer be seen as an optional extra to be considered once more pressing concerns such as wealth creation or national security have been dealt with.

This assessment shows that healthy ecosystems are central to the aspirations of humankind.

… this is not a counsel of despair. The natural balance sheet we bequeath to future generations depends on choices made at every level and in every corner of the planet – from the head of a village in Bangladesh to a corporation board in a New York skyscraper, from international gatherings of finance ministers to consumers in a Brazilian furniture store.

The crucial importance of motivation - There are, perhaps, some grounds for cautious optimism. Humans, after all, have extraordinary ingenuity – given the motivation. Putting a man on the moon and the development of nuclear weapons and computers are among countless examples.

The key word here is ‘motivation’. It is reasonable to suppose that, given the motivation, humankind could successfully overcome all of these ecological problems. But at present, the motivation to do so is lacking – despite all the growth in environmental awareness. Economic growth and increase in material standard of living still has top priority in the decision-making process at the governmental level, and probably also at most other levels in our society. This is a deeply ingrained characteristic of the dominant culture of our time.

No motivation without understanding - The necessary motivation to take effective action to achieve ecological sustainability will not come about until there is a vastly improved understanding, right across the community, of the processes of life, the human place in nature and the health needs of people and of the ecosystems on which they depend.

Urgency - The seriousness and urgency of these issues cannot be overstated, for if a society is not ecologically sustainable it cannot, in the long term, be sustainable in any other way.

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This paper as a [135KB pdf]

Related content

• • Ecological issues

Stephen Boyden

Contents:

Civilisation and warfare

Hunter-gatherers,
farming societies,
early cities,
peaceful cities,
Christianity

Scale of homicide in warfare

warfare and disease

Weaponry

before explosives,
explosive weapons,
aircraft,
Nuclear weapons,
other weapons of mass destruction

Civilisation and warfare

Hunter-gatherers

We do not know to what extent our Palaeolithic ancestors engaged in warfare. However, evidence from recent hunter-gatherer groups suggests that violent conflict between groups involving fatalities occurred from time to time, but that it was not a constant feature of hunter-gatherer societies.

Farmers

Certainly large scale and highly organised homicide has been one of the hallmarks of civilisation. Some authors have suggested that it all began with the domestic transition, when people came to possess commodities that were coveted by others, like domestic animals and stored grain. However, organised violence between groups is not an inevitable outcome of agriculture. There have been plenty of farming societies that have lived at peace with their neighbours for long periods of time, and archaeological evidence suggests that the farmers of the valleys of the Tigris and Euphrates Rivers before the advent of cities, as well as the early Neolithic people of central Europe, were among them.

On the other hand, it is also clear that violent hostilities were common in some farming communities from early times. Towards the end of the Neolithic phase in Europe the relative peace was shattered by the aggressive ‘battle-axe’ people who were intent on warfare and political domination; and there is evidence that around 5000 years ago farming people in the south of England built, and attacked, fortified settlements. In more recent times, several groups of slash-and-burn agriculturalists in South America, such as the Yanomami, have been almost constantly at war with their neighbours.

It has been suggested that the fact that villagers in some regions were nearly always at war with neighbours, while in others they were not, can be explained in terms of differences in local ecological conditions. Competition for scarce resources is seen to be the underlying cause of conflict. My own view is that the chief determinants lay in differences in cultural assumptions rather than biophysical conditions.

Early cities

It was soon after the establishment of the early cities in Mesopotamia that organised violence between large groups of people came to be accepted as normal. By around 5000 years ago highly organised fighting among the city states and between city states and barbarian raiders was commonplace. People were immersed in cultural systems which glorified the military exploits of their forefathers and which characterised other human populations as enemies. The heroes of society were the successful commanders and intrepid warriors.

For centuries history books have extolled the prowess of ‘great men’ who commanded armies or navies which succeeded in annihilating large numbers of perceived enemies. An example is provided by the words of the Greek historian Plutarch, a writer otherwise generally known for his humanitarianism. He writes in the following appreciative terms of Julius Caesar:

Justification of war

Nevertheless, from the beginning warfare usually had to be ‘justified’, in that wars were waged in the name of a god, or at least of an empire. The following words from the Book of Joshua provide a good example of the former.

And Joshua at that time turned back and took Hazor, and smote the King thereof with the sword: for Hazor beforetime was the head of all those kingdoms. And they smote all the souls that were therein with the edge of the sword, utterly destroying them: there was not any left to breathe: and he burnt Hazor with fire. And all the cities of those kings, and all the kings of them, did Joshua take and smote them with the edge of the sword, and he utterly destroyed them, as Moses the servant of the Lord commanded.

The professional soldier came to be accepted as a natural and necessary component of most urban societies and for millennia the sword held pride of place among human artefacts as the symbol of masculine virtue.

Peaceful cities

On the other hand, the remains of Caral – the oldest known city in the Americas – show no trace of warfare. No battlements and no weapons have been found. Similarly, excavations at Harappa and at Mohenjo-daro in the valley of the Indus River in Pakistan have revealed no indication of military activity until the very end of their history. Another striking example is provided by the cities of the Minoan civilisation on the island of Crete. At a time in the Bronze Age, when warfare and empire building were gaining momentum throughout the Near East, the people of Minos were creating ‘one of the most graceful civilisations man has ever achieved’.  The enthusiasms of the people of the city of Knossos were athletics, elegant clothing and the natural world.

Asoka

There have, of course, been occasional leaders who have personally renounced violence in all its forms. An especially interesting example was Asoka, who discarded a strong cultural tradition of violence to embrace the cause of peace. He had inherited an empire which extended from Afghanistan to Mysore and which had been built through military force by his grandfather. Around 262BC, Asoka was in the process of further extending this empire when he found himself involved in a war with the Kalinga people. His army was victorious, and a hundred thousand persons were slain. The experience of this particular war brought about a remarkable change in Asoka. Suddenly he became acutely aware of the intensity of human distress caused by the fighting, and he turned towards non-violence as the creed of his life. He changed his personal religion and adopted Buddhism which, of the religions of India at that time, was most strongly identified with the principle of Ahisma.

Christianity

Non-violence did not become important in the religions of the Near East before the teachings of Jesus, but after that time it was probably believed in and practised by Christians for a few hundred years. However, by the 4th century AD cultural developments had completely overridden these fundamental tenets of Christianity, and large-scale homicide was once again acceptable, so long as one was fighting on the side of God.

Scale of homicide in warfare

Cultural evolution in Europe and Asia over the past 5000 years has been associated with a progressive increase in the number of people actively participating in, or affected by, wars. In the 1914-1918 World War, about 53 million men were mobilised in the armed forces, and 8 to 10 million were killed. In 1914, 640 000 French soldiers lost their lives during the four months from August to November. The army of the United Kingdom lost over 400 000 men in the battle of the Somme, 50 000 of them on the first day.

World War II differed from previous conflicts in that aerial bombing of cities resulted in high civilian casualties. The armed forces of the warring nations numbered about 30 million and the total number of individuals killed, military and civilian, was probably between 35 and 40 million.

Role of disease

Of course, not all deaths in warfare have been due to physical injuries inflicted by enemies. Malnutrition and infectious disease have also taken their toll. The story of the Spanish invasion of Mexico under Hernando Cortez early in the 16th century AD provides an example. One of the Spanish expeditions that landed at present-day Vera Cruz in April 1520 included an African slave who was infected with smallpox. The disease soon appeared in the native American-Indian population, and because these people had not had any previous contact with the smallpox virus, it spread extremely rapidly. By September of that year, the disease had reached the towns around the lakes in the Valley of Mexico, including the Aztec capital, Tenochtitlan. About half the population of this city and of the surrounding region died within six months. This happened at a time when the Aztecs had been gaining the upper hand in the conflict with the Spanish forces. Because most of the Spaniards were immune to the disease, they were able to exploit the situation to their military advantage, eventually overcoming the indigenous armies.

In fact, until quite recently microbes have caused more deaths among warriors than combat itself, as reflected in the following figures:

• Crimean War (1854-1856) – about 60 000 men on both sides killed or died of wounds, about 130 000 died of disease
• American Civil War (1861-1868) – about 220 000 men killed or died of wounds, about 400 000 from infectious disease;
• South African War (1899-1902) – of the British forces, 7534 were killed or died of wounds, 14 382 died of infectious disease.
• The influenza epidemic immediately after World War I killed at least 21 million people, and probably many more, compared with the eight to ten million soldiers killed in action.

Weaponry

Before explosives

Early in human history, people applied their tool-making prowess to the manufacture of weapons. In primeval times these were used mainly in hunting animals for food, although sometimes they would have been used in combat between human groups. The weapons were broadly of two classes. First, there were close-range weapons, like clubs and hand axes, which consisted in essence of an extension of the human arm or hand. They were used for directly striking the enemy. Second, there were projectile weapons, such as stones, sticks and boomerangs, which were thrown at the target, initially by the human arm, but later by other means, as in the case of the bow and arrow.

After the advent of urban civilisation most weapons were designed especially for killing people. They also fell into the two classes – close range and projectile weapons. There was a simultaneous development of armour, made of leather or metal, intended to provide soldiers with some protection against the enemy’s weapons.

The spear is the most ancient of the weapons used in warfare. In one form or another it had been used for tens of thousands of years in hunting animals for food, originally with a shaft of wood and a spearhead of stone. When techniques of metallurgy were developed spearheads, and sometimes spear shafts, were made of copper or bronze. The soldiers of Sumer 5000 years ago, and of those of the Old Kingdom of Egypt 4700 years ago, were equipped with metal spears. The cavalry version of the piercing spear, the lance, was developed later.

The other important short range weapon, invented and developed especially for cutting, or thrusting into, flesh, was the sword. This consisted of a pointed blade, which might be straight or curved, with a handle, or ‘hilt’ and a cross-guard. Soldiers often became emotionally attached to their swords and even gave them names. Famous examples from history and legend are Charlemagne’s ‘Joyeuse’, and King Arthur’s ‘Excalibur’.

Gunpowder

The discovery of the explosive potential of gunpowder was a seminal development in the history of warfare. Roger Bacon, who lived from AD 1214 to 1292, wrote a formula for gunpowder as follows: seven parts of saltpetre, five parts of young hazel wood (charcoal) and five parts of sulphur. He stated that this mixture would explode, and that it could cause an enemy to be blown up, or at least to flee in terror. It is believed that gunpowder was used in warfare around AD 1250 by the Moors, who put half to one kilogram of the explosive mixture into an iron bucket that had a small touch-hole at the bottom. They placed a pile of stones on top of the gunpowder, which was then ignited. The resulting explosion propelled the stones through the air, ideally towards the target.

The first cannons were made of bronze and were introduced at the beginning of the 14th century. They were replaced by iron cannons half a century later. The first military event of importance in Europe in which artillery played a significant part was the capture of Constantinople by the Ottoman Turks in 1453.

Gunpowder was also applied to the development of guns to be held in the hand, although for a long time they were not very effective. This was partly because of the need to keep a match alight in the combat situation, partly because of the difficulty in keeping gunpowder dry, and partly because of the clumsiness of stuffing lead bullets into the gun’s barrel with a ramrod. Effective rifles were not used for military purposes until the Thirty Years War (1618-1648).

Machine guns, air raids and rockets

These developments were associated with some other important changes in the ‘art of warfare’. By the time of the First World War some combat was no longer on face to face or one to one basis. The single touch of a trigger of a machine gun could kill a dozen men and one artillery shell could destroy many individuals who were completely out of sight of the gunners. This fundamental change in the nature of armed conflict had further progressed by the time of World War II, when bombing by air became important and new projectile weapons in the form of various kinds of rockets were introduced. Technology now exists which makes it possible for deliberate hostile action by a small number of individuals to cause the death of millions of people thousands of kilometres away.

Nuclear weapons

During the last part of World War II, Germany and the United States were competing to be the first to produce nuclear weapons. Then, three months after the capitulation of Germany, on the 6th August 1945, a nuclear bomb was dropped from an American aircraft onto the city of Hiroshima in Japan. At least 140 000 people, or about 40 per cent of the city’s population, were killed immediately or died soon afterwards. Buildings were flattened over an area of 13 square kilometres. Three days later, another bomb was dropped on the Japanese city of Nagasaki, and about 80 000 people were killed outright.

After this war governments representing opposing political ideologies directed immense financial resources and human effort into the development of nuclear weapons. As a result bombs now exist with an explosive power a thousand times greater than that which was dropped on Hiroshima. Nuclear weapons range in strength from the equivalent of around one hundred tonnes to twenty million tonnes of TNT, depending on the particular use for which they are designed.

The increase in the power of bombs during the twentieth century can be illustrated by the following analogy. If we imagine the explosive power of the biggest bombs in World War I to be represented by a pea, then the most powerful weapons (other than the atomic bombs used at Hiroshima and Nagasaki) used in the Second World War would equal the size of a large plum. The Hiroshima bomb would be equivalent to a sphere of about 0.5 metres across, and the most powerful bombs now ready for use would have a diameter of 5 metres.

Ecological impacts of nuclear war

The ecological and human impacts of a nuclear conflict in the future would depend on the scale of the war and on the geographical distribution of the nuclear explosions. Even if only one tenth of the existing nuclear weapons were used, the numbers of people killed by fire, blast and fall-out would be astronomical. Most commentators consider it likely that a major nuclear war would leave some survivors, especially in the southern hemisphere.

There would also certainly be massive damage to the planet’s ecosystems resulting from nuclear radiation and widespread fires. It could well be that the biosphere as we know it today would collapse and would no longer be capable of supporting a human population.

Other weapons of mass destruction

Mention must also be made of the enormous amount of effort and resources that have been devoted in modern high-energy societies to the development of other sophisticated weapons of mass destruction. Thus, apart from the advances in nuclear armaments, great progress has been made in the development and production of chemical and biological weapons. However, horrendous they may be, their impact on civilisation and on other life forms would be small in comparison with that of a nuclear war.

Human society as a whole spends over US$1 million per minute on the development and manufacture of homicidal devices. In six hours, more money is spent on the manufacture of arms than was spent by the world community in bringing about the eradication of smallpox.

Conclusion

Clearly there is nothing in human nature that precludes humans from deliberately slaughtering each other.

On the other hand, there is also nothing in human nature that rules out the possibility of different human groups living at peace with each other for long periods of time.

Whether or not humans engage in armed conflict is obviously determined by a range of factors, including pressures associated with scarcity of resources and over-population. But especially important among these factors are the conflicting beliefs and assumptions of different cultural systems and the extent to which people allow themselves to be brainwashed by absurd cultural delusions of the kind that lie behind most warfare.

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