Ecology, Conservation and the Human Role

Ecology is a word that has only recently crept into everyday speech. In a few words, it means the relationship between living organisms and their environment. These living organisms - life itself - are perhaps the most amazing thing about the universe and our tiny world within it. Life has been well called the biospheric membrane wrapped around the Earth. E O Wilson once wrote of a hypothetical journey outwards from the centre of the Earth.

"For the first twelve weeks you travel through furnace-hot rock and magma devoid of life. Three minutes to the surface, five hundred meters to go, you encounter the first organisms, bacteria feeding on nutrients that have filtered into the deep water-bearing strata. You breach the surface and for ten seconds glimpse a dazzling burst of life, tens of thousands of species of micro-organisms, plants and animals within a horizontal line of sight. Half a minute later almost all are gone. Two hours later only the faintest traces remain consisting largely of people in airliners who are filled in turn with bacteria."

The wafer-thin repository of life is contained within the atmosphere, itself a turbulent highly reactive chemical mixture of gases. That turbulent mixture has a stability of its own but is in constant evolution.

From outside the Earth system, solar radiation has gradually increased. How it falls on the Earth's surface is subject to variations in the Earth's orbit, its tilt and the way it spins. Then there have been hits from space. Perhaps the most devastating was 250 million years ago when the effects caused the extinction of some 90 percent of marine species. More notorious was the bolide of 65 million years ago which so changed atmospheric conditions that it ended the long dominance of the dinosaur family.

From inside the Earth system the slow movement of tectonic plates profoundly affects life in all its aspects. Land masses crash and separate. Mountains rise and fall. Sometimes volcanic dust shrouds the Earth. Ocean currents take new tracks. Throughout living organisms have adapted themselves to new circumstances while helping to create them.

Once life had started it began to evolve, and the atmosphere with it. By preserving and making use of water, carbon, hydrogen and sunlight, living cells transformed their physical surroundings and the rocks, muds and gases of which they were composed. Its detritus is under our feet. Photosynthesis and oxygenation are the two driving forces which have made the world we know.

The complexity of life, now and in the past, is beyond measurement. As it has evolved over hundreds of millions of years, its proliferating parts have remained interconnected, and in different degrees interdependent. We ourselves, partly composed of bacteria, are walking zoos. Obviously living organisms find some physical circumstances more comfortable than others, and take advantage of them. Less obviously, living organisms through the familiar mechanisms of natural selection, genetic mutation, symbiosis and chance are able within limits to establish the physical circumstances which best suit them.

Neither climate nor life will continue indefinitely. Eventually our Sun will become a red giant, and expand to near the orbit of the Earth. Long before then life on Earth will be extinct.

My theme tonight goes beyond the phenomenon of life to its conservation and the human role. Our own lives are very short, and we have to stand well back to appreciate the extraordinary changes both in the biospheric membrane surrounding the Earth and in the behaviour of our own species since the end of the last ice age with its final spasm some 11,500 years ago.

From then onwards the handiwork of this one animal species has become increasingly evident. From North America to Australia, humans hunted down the big mammals, and the patchy transition from hunter gathering to settled agriculture, with steep increases in human numbers, led to deforestation on a vast scale, with changes in global ecology ranging from very big to very small organisms.

The growth of cities accelerated all such changes; and the industrial revolution, which began around 250 years ago, accelerated them still more. An observer from outer space would see more changes in the last 200 years than in the preceding 2000, and more changes in the last 20 years than in the preceding 200. He might indeed conclude that the Earth was suffering from some biological calamity, or case of malignant maladaptation, in which a species, like infected tissue in an organism, multiplies out of control, affecting everything else.

Some of you may have heard of some remarkably gloomy predictions about the future from the Astronomer Royal Sir Martin Rees. In his new book Our Final Century (the publishers removed the question mark after the title), he explores the dangers arising from human inventiveness, folly, wickedness and sheer inadvertence. The ramifications of information technology, nano-technology and nuclear experimentation and the rest have still to be understood and explored. His conclusion is to give our civilization only a 50 percent chance of survival beyond the end of this century.

I do not necessarily go as far as he does. But I think we forget the ephemeral, chancy, precarious, contingent character of all human civilization, not unlike evolution itself. Things can go backwards as well as forwards. Indeed the only certainty, as Lucretius once said, is change itself.

There have been some 30 urban civilizations before our own. All eventually crashed. Why? The reasons range from damage to the environmental base on which they rested to the mounting costs in human, economic and organizational terms of maintaining them: in short their complexity.

The linkages were explored in a recent series of articles in Science magazine. The series began with the effects of human population increase and of damage to biodiversity with the global ecosystem. Taking the case of biodiversity, Martin Jenkins wrote:

"With the harvest of marine resources now at or past its peak, terrestrial ecosystems will bear most of the burden of having to feed, clothe and house the expanded human population."

Already nearly half of the Earth's land surface has been transformed by direct human action, and the indirect effects are beyond calculation.

The result with big regional variations is almost bound to be conversion of more land to crops, with increasing loss of forests and natural habitats, and degradation of land, particularly in tropical countries. This means continued, even accelerating loss of natural ecosystems, and their replacement by less diverse, often intensively managed systems of non-native species.

At some point, Martin Jenkins wrote, some threshold may be crossed, with unforeseeable but probably catastrophic consequences for humans. These consequences could be brought about by a variety of factors, such as abrupt climate shifts, albeit ones in which ecosystem changes might have played a part.

Where this threshold may be is simply impossible to predict. The Earth has never been in this situation before. These points were well brought out in a remarkable Declaration published by some 1500 scientists from the four great global research programmes at Amsterdam in July 2001. They stated squarely that:

"Human activities have the potential to switch the Earth's System to alternative modes of operation that may prove irreversible and less hospitable to humans and other life… the Earth's System has moved well outside the range of the natural variability exhibited over the last half million years at least. The nature of changes now occurring simultaneously in the Earth's system, their magnitudes and rates of change are unprecedented. The Earth is currently operating in a no-analogue state".

"The accelerating human transformation of the Earth's environment is not sustainable. Therefore the business-as-usual way of dealing with the Earth's System is not an option. It has to be replaced - as soon as possible - by deliberate strategies of management that sustain the Earth's environment while meeting social and economic development objectives".

At least we can agree with Crutzen and Stroemer who have named the current epoch the Anthropocene in succession to the Holocene. The Anthropocene began with the industrial revolution. Since then living conditions for most people, measured in terms of material wealth and longevity, have greatly improved. But all change has been at a price. While we have been increasing output of goods of all kinds, we have been running down, despoiling and often wasting the resources from which they are derived. If our animal species among millions of others is to survive and prosper, we need to use our unique capacity to think.

For the moment there are six main things for us to think about: human population increase; degradation of land and accumulation of wastes; water pollution and supply; climate change; energy production and use, and destruction of biodiversity. Of these factors population issues are often ignored as somehow too embarrassing or mixed up with religion and the ideology of development; most people are broadly aware of land and waste problems, although far from accepting the remedies necessary; water issues have had a lot of publicity, and already affect most people on this planet; climate change with its many uncertainties is also broadly understood, apart from by those who do not want to hear about it; how we generate energy while fossil fuel resources diminish and demand increases is another conundrum; but damage to the diversity of life has somehow escaped most public attention.

It has been suggested elsewhere that humans have three biological characteristics which dominate their behaviour. First is their propensity to use and exploit whatever resources they can find as if there were no limit. Other species may share this propensity, but none has anything like ever increasing human technical skills in doing so. In short humans are too clever by half.

Our second characteristic is our curiosity, inventiveness and love of play which tends to transform every activity, whether politics, war or science, into games which induce self-absorbed behaviour, sometimes beneficial in the short term, but often out of touch with the long term realities of the environment. We see ourselves as so special that Nature herself is our servant.

Our third characteristic is our intellectual predilection for putting subjects into compartments, thereby missing their connections and inter-relationships. As a result we fail to see, let alone comprehend the big picture. Yet it is only through seeing the big picture that we can hope to draw sensible conclusions, and take decisions consistent with the circumstances in which we find ourselves together with the other millions of organisms affected by human activities.

Then there is the way in which we treat each other. There is a widening gap between the world's rich and the world's poor, and disproportionate consumption of the Earth's resources. At present about 20 percent of the world's people consume between 70 percent and 80 percent of its resources. That 20 percent enjoy about 45 percent of its meat and fish, and use 68 percent of electricity (most generated from fossil fuels), 84 percent of paper, and 87 percent of cars. The dividing line between rich and poor is not only between countries but also within them. There are the globalized rich and the localized poor, and according to the latest report from the United Nations Development Programme the gap between them is ever widening.

What can we do about this unique combination of problems with their widespread ecological effects? What should be the human role? The problems are so intimidating that most people, including politicians and leaders of all kinds, simply do not want to confront them, or feel capable of doing so. The bridge between science and politics is always long and rickety.

There have been many conferences, some international agreements like those on climate change and protection of biological diversity, and three world summits (Stockholm 1972, Rio de Janeiro 1992, and Johannesburg 2002). But even if some governments, including our own, have begun to take action on some of the issues, for example energy and transport policy, most have continued to ride a tide which carries them ever further in the wrong direction. The biggest villain is the biggest polluter. The Bush Administration in the United States seems wilfully determined to pretend that the problems are unproven, and to ignore the advice of its own as well as of the world's scientists. The world is warming up at an accelerating rate, with consequences which must affect all humanity.

I suppose that the top priority for us all to assess the value that we place on the environment. We have to see it as a kind of endowment of natural capital. It is the means by which we live our lives. I do not think that anyone would disagree with the statement by a well-known economist that "the economy is a wholly owned subsidiary of the environment". In short without a healthy environment, there can be no healthy economy".

But there is a real difficulty on how to assess health. The ideologues of free trade like to suggest the price mechanism. But as another distinguished economist once remarked: "Markets are superb at setting prices, but incapable of recognizing costs". Prices are indicators. But we have to make sure that they tell the truth about costs. A pricing system should include not only the traditional costs, but also those involved in replacing the resource, and those of the damage that use of the resource may do. We should heed the words of a former Vice President of Esso for Norway and the North Sea who once said: "Socialism collapsed because it did not allow prices to tell the economic truth. Capitalism may collapse because it does not allow prices to tell the ecological truth".

Not surprising since the enormity of the environmental crisis has become clear, efforts have increased to bring greater compatibility between conventional economics and sustainability. Not everything can be given monetary or economic values, and it is sometimes misleading to try to do so. How can we value the loss of a species, or such ecological services as the air we breathe? We need to measure wealth, welfare and the human condition in different terms. We also need to redefine development and recognize the needs and strengths of different countries. There is no universal blue print. It is local experience and potentiality which have the most importance.

Perhaps our next priority should be better understanding and care of the Earth and its living systems of which we are such a small but immodest part. Hence the importance of the current Millennium Ecosystem Assessment due to report next year, and - in the next ten years - the Tree of Life project to demonstrate relationships between organisms by descent. The Secretariat of the Convention on Biological Diversity will also produce the second edition of its Global Biodiversity Outlook this year. The United Nations proclaimed 22 May the International Day for Biological Diversity to increase understanding and awareness of biodiversity issues. The theme for International Biodiversity Day 2004 will be Biodiversity: Food, Water and Health for all. The idea is to link biodiversity issues to the UN Millennium Development Goals. How much public impact this kind of thing will have is doubtful.

Will it lead to any action? There are good ethical, aesthetic, economic, and ecological reasons for conserving biodiversity. Ethical and aesthetic arguments are of enormous, indeed primal, importance for the psychological health of any society, but they are usually unpersuasive against short term arguments of self interest. Our economic interest in biodiversity is obvious. We need to maintain our own good health as well as that of the plants and animals, big and small, on which we depend for food. We have our place in the food chain like any other creature, and are more vulnerable than most as predators at the top of it.

The realization of how much we rely on other biota for natural services is perhaps the most difficult message to get across. We rely on forests and vegetation to produce soil, to hold it together and to regulate water supplies by preserving catchment basins, recharging groundwater and buffering extreme conditions. We rely upon soils to be fertile and to absorb and break down pollutants. We rely on coral reefs and mangrove forests as spawning grounds for fish and wetlands, and on deltas as shock absorbers for floods.

Likewise we rely on the natural processes of recycling and waste disposal. We rely upon the current balance of insects, bacteria and viruses; and we assume the health of plants and animals unless we find to the contrary. Yet few realise the extent to which we have been appropriating the resources of the earth for our own purposes. Already we use - or abuse - some 40 percent of total photosynthetic production on land.

Perhaps traditional concepts of human domination of nature make this level of reliance hard to accept. Tackling the loss of biodiversity requires thinking that looks beyond human use. One of the lessons of Gaia theory is while life itself may be, as Lynn Margulis put it, "a tough bitch", Gaia has no particular tenderness for humans.

Certainly we need to assess more accurately the human capacity for harm to ourselves as well as to other organisms. Here the applications and misapplications of science and technology are crucial. Big changes will come in how we derive our energy as we tackle climate change and exhaust our viable fossil fuels. Solar, wind and biomass will all become more common. Nuclear fusion technology is on the horizon. The hydrogen fuel cell may replace the internal combustion engine.

Technology will only ever be a part-answer. To reduce global warming technologists have suggested that mirrors in space or the seeding of clouds may increase the Earth's albedo. But there is still a danger of acidification of the ocean surface if we do not reduce the amount of CO2 in the atmosphere. Technology is often a double-edged sword, often throwing up unexpected consequences, sometimes graver than the difficulties they were meant to resolve. The chlorofluorocarbon (or CFC) story is a good illustration. Once thought harmless, they lead to depletion of the cover which protects us from certain wavelengths of ultra-violet radiation, and in addition are a powerful greenhouse gases.

This brings me to prospects for our future. Let us assume that we survive this century, and something like our civilization with us. In peering further ahead it may be useful to jump a few hundred years, accepting that our ability to look even twenty years ahead is extremely limited. Perhaps the single biggest hazard is climate change. Just as the warming that followed the ice age transformed human society, so the changes already in train could transform it again. Then if statistical projections from the past have value, there will certainly have been sudden disruptions before 2500, whether volcanic explosions, earthquakes, impacts of extraterrestrial objects, or even destructive wars using unimaginably horrible weapons. Ecosystems will be drastically changed, as after other extinction episodes in geological history. Human health will be affected by the development and spread of new pathogens.

How our successors, if there be such, will react to these new circumstances we cannot predict. We must always expect the unexpected. But it is hard to believe that there will be anything like current human numbers in cities or elsewhere. It has been suggested that an optimum population for the Earth in terms of its resources would be nearer to 2.5 billion rather than - as now - 6.2 billion and still rising. Communities are likely to be more dispersed without the daily tides of people flowing in and out of cities for work. People may even wonder what all those roads were for.

There is also the possibility, however sinister, of differentiation of the human species. H.G. Wells invented Eloi and Morlocks (those up above and those down below), and at the time, more than a century ago, it seemed an amusing fantasy. No longer. Redesigning humans has become a real possibility. Through genetic manipulation humans could split into distinct varieties and over time into subspecies. It is worth remembering how vulnerable even the Eloi were. Some of these ideas were explored by Lee Silver in his book Remaking Eden in 1998.

Then there is the development of information technology and its myriad implications for our lifestyles. On the one hand humans may take enormous advantage from such technology and thereby be liberated from many current drudgeries. On the other hand they may become dangerously vulnerable to its breakdown, and thereby lose an essential measure of self-sufficiency. Already dependence on computers to run our complex systems, and reliance on electronic information transfer, are having alarming effects. Here industrial countries are far more vulnerable than others. Just look at the effects of single and temporary power cuts. More than ever individuals feel out of control of even the elementary aspects of their lives.

The implications for governance reach equally wide. Already there is a movement of power away from the nation state: upwards to global institutions and corporations to deal with global issues; downwards to communities of human dimension; and sideways by electronic means between citizens everywhere. There is a wide range of possibilities including forms of dictatorship and disaggregation of society.

In looking for some form of global governance for the common good, there is much that needs to change. The one world superpower is not leading us where we need or want to go. Global institutions are still feeble by comparison. The United Nations is fundamentally an association of sovereign states, even if real sovereignty is leaking away from them all the time. Beyond and above the international debating society which is the UN General Assembly is the Security Council for the regulation of peace and war; the International Court of Justice to which few states now risk submitting their disputes; the numerous Specialized Agencies and Associated Bodies with poor co-ordination between them; the multilateral corporations, the banks, the media controllers, the drug empires, the criminal syndicates and others, essentially outside the current system; the non governmental organizations which, though unaccountable except to their members, try to represent the citizens' interest, particularly in the field of the environment and human rights; and now increasingly the information systems of the internet and the world wide web, also outside the system.

The problems of politics will be as difficult as they are today: how to ensure greater citizen participation without creating chaos; how to establish forms of accountability to ensure that governance is by broad consent; and how to establish checks and balances to protect the public interest, and ensure enforcement without abuse.

There is a rough ride ahead. In a complex world, for those that can, the temptation may be to switch off and turn to bread and circuses. Education will be vital. Every individual must feel that he and she can do something and take increased responsibility for their actions. Governance cannot protect the public interest if the public neither know, nor care, what that wider interest may be.

Let us hope that by then humans will have worked out and will practice an ethical system in which the natural world has value not only for human welfare but also for and in itself. They may also be involved in spreading life beyond the Earth and colonizing Mars or other planets. The opportunities for our species seem as boundless as the hazards.

T. H. Huxley once wrote, "I am too much of a sceptic to deny the possibility of anything". Such scepticism may be wise, but it does not allow us to opt out of making choices, and we may have to make many if we are to bequeath a healthy Earth to our children and grandchildren. In the future people could well look back on us today as a messy, short-sighted, wasteful, crude and aggressive lot. Is that what we are? In the meantime as Boswell remarked to the philosopher, cheerfulness will keep breaking in.