David Attenborough hit the headlines yet again in 15 May 2009 with an opinion piece in New Scientist. This is a quotation:

‘He has become a patron of the Optimum Population Trust, a think tank on population growth and environment with a scary website showing the global population as it grows. "For the past 20 years I've never had any doubt that the source of the Earth's ills is overpopulation. I can't go on saying this sort of thing and then fail to put my head above the parapet."

There are nearly three times as many people on the planet as when Attenborough started making television programmes in the 1950s - a fact that has convinced him that if we don't find a solution to our population problems, nature will:
"Other horrible factors will come along and fix it, like mass starvation."

Bob Hawke said something similar on the program Elders with Andrew Denton:

ANDREW DENTON: You looked genuinely sad before when you were talking about the world that our children are coming into, are you optimistic for the future of the planet?

BOB HAWKE: I am by nature and I have all my life by nature been an optimist, Andrew, but I’ve got to say that when I look at the facts now in this world there are not many grounds for optimism. We’re you know, take the elements and just take population for a start. Population is exploding. We’ve got to do something about you know getting a sustainable population level and of course this gets back to poverty, it gets back to the education of women and so on. We’vegotthe problems of food supply, of global warming, massive increases in the population. Now these are not the figments of Bob Hawke’s imagination. These are facts. Ah you’ve got you know over a billion people in the world of over six million now living in absolute poverty and half the world’s population living in very meagre situations.

ANDREW DENTON: It seems to be an insurmountable problem the question of over-population and over-consumption and that we have finite resources and that we’re finding more and more ways of using them. What is the hope?

BOB HAWKE: The answer to that question is how are developed nations going to be persuaded of the need for action? I mean it’s, how does the message get through? I mean you look in terms of political leadership. There are no great political leaders around.

Those who are familiar with my various essays, dating back to the seventies, will find these words familiar.

Yet there are some who feel that humanity has a special place in the universe and that somehow this special place gives us a right and a duty to fill the universe with as many human beings as possible.

This is patently wrong. Humans have no central place in the universe, or on this planet. The universe is around 13,700 million years old; our planet is around a quarter of this age and that there are in all probability, thousands of billions of similar planets in the universe. Human beings, in our most recent form, have been on this planet for micro instant; no more than 70,000 years; or .0000005 of the life of the universe.

Like the earth's path around the sun, the sun rotates around our galaxy, one of billions, once every 250 million years; or one galactic year. The dinosaurs dominated this planet less than six galactic months ago and we have been here for less than one thousandth of a galactic year. Given the rate of evolution and extinctions on earth, it is certain that neither humans, nor the other plants and animals we are familiar with, will be here by the end of the remaining half of this galactic year. But we will not be missed. There is no reason to believe that the universe will not continue into the future for thousands of galactic years after we are gone.

In this context humans are an insignificant animal, on an insignificant planet, circling an insignificant sun, in an insignificant galaxy for an infinitesimal time. In this context it matters little what we do. But to me and you it is as important as anything can be.

All animals and plants on earth are driven by basic biology to grow exponentially for as long as conditions are favorable. All successful complex organisms have means of reproducing in an unconstrained manner for as long as they are unconstrained by resources and space and lack competition. In this respect humans are no different to other animals and plants.

For many millennia human numbers were relatively small, fluctuating with climate conditions, food availability, disease prevalence, animal predation and territory; the latter often by wars between ourselves. But humans are unique among animals. We have developed technology and accumulated knowledge that extends our natural capabilities. At different times in the past we have been able to gain additional advantages as a species that allowed our numbers to expand.

Initially this expansion was geographic, across all the continents on the planet from around 70 to 10 thousand years ago. Globally our numbers grew from a relative handful to perhaps one million. The latest anthropology, based in part on DNA analysis, shows that there was a cultural, and possibly evolutionary, revolution in human development 50,000 years ago; leading to ritualistic burials, clothes making and the invention of complex hunting techniques and probably the advent of religion. Recent developments may be more social and technological than genetic. Agriculture began 10,000 years ago; the manufacture of metals about 6,000 years ago; systematic writing about 5,000 years ago (possibly earlier).

The widespread use of iron began about 3,000 years ago and its use to make machines to capture and convert energy, 300 years ago; just four lifetimes. This allowed the replacement of human effort by harnessing fire, combustion, more effectively. In a brief ten thousand years there have been huge advances in human capability and consequently our viability as a species.

At each point of increasing viability, human population numbers leapt upwards.

There were about a billion of us in 1800 and over the next 120 years this number doubled as colonial powers introduced systematic agriculture and rail transportation; together with sewerage and clean drinking water; across the planet. In the twentieth century, building on the successes of the European and Scottish enlightenment in the previous century, we adopted a more rigorous scientific approach to knowledge and truth. We soon acquired vastly increased capabilities including: powered flight; the mass-produced motor car and tractor; nuclear power; telecommunications; electronics; biotechnology; science based medicine; space flight; labour saving domestic appliances; and many other developments.

Human population numbers exploded.

With the progressive introduction of the tractor and broad acre agriculture from the 1920s ; there was a dramatic acceleration in population growth. In just 40 years our numbers grew by another billion; to three billion by 1960. Then came the green revolution, when new crops were engineered; initially using conventional breeding. These together with mass produced, chemically engineered, fertilisers and insecticides; new methods of irrigation; electricity for pumps, processes and refrigeration; a huge scale increase in agricultural machinery; new food transportation, storage and processing infrastructure and methods; as well as widespread use of antibiotics and new science based medicines; facilitated even faster growth. In just 50 years we 'bred up' by a further four billion people.

These new capabilities and understandings have brought generally higher living standards and longer life expectancy across the globe. Corresponding changes in mores, education and practices have already lowered fertility in culturally advanced populations. But throughout this time the poorest people have been the main engine of growth; the most numerous and youngest; living on the margins; subsisting in abject poverty on the verge of starvation. Many still do starve periodically when conditions fluctuate. The difference between now and 50 years ago is that today over twice as many, 2.7 billion, are subjected to this inhumanity.

We are patently in the midst of a human population crisis; driven on by the same circumstantial lack of constraint that drives mouse plagues; and, it seems, just as helpless in preventing the catastrophe that is to come. A quick review of the comments at the end of the New Scientist article, by presumably well educated and informed people, is ample demonstration of the overweening confidence of some that we can go on in this way, and even when we perceive the danger, our inability to do anything about it.

We have the knowledge and skills to make things better for humankind without allowing our numbers to increase to consume the benefit. World poverty is on the decline in many areas, particularly in China and South East Asia and other places where fertility has been successfully lowered. We do not have to be like the mice that periodically multiply in plague proportions in rural Australia and just as quickly die away when they have destroyed the conditions that allowed them to multiply.

But we have to get things right for ourselves. And we have to act quickly. If we do choose to do nothing nature will. Ever-growing human numbers will destroy our favourable environment; our numbers will then, inevitably, collapse back to a sustainable level, occasioning huge loss of life; and perhaps the demise of modern civilisation itself. Should civilisation collapse we would be back to a maximum population of a few hundred million.

Of course life on earth won't be threatened, it will continue for many millions (and perhaps billions) of years after we are gone. Most of the ever evolving animals plants and bacteria will continue as they do now; day to day; hour to hour; or second to second; carelessly; not able to perceive or appreciate the grandness of their coming and going. It is our gift and burden as ‘modern’ humans that we are able to do both.

C’est la vie.

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