Jean-Christophe Vie, BBC Green Room 15 Jul 08;
Despite our ever-increasing knowledge of the natural world, too many people still see it as just another means to make money, says Jean-Christophe Vie.
In this week's Green Room, he setsout his argument why the planet's rich diversity of life needs to be preserved in its entirety.
In the world of economics, what nature provides for us is often seen in terms of immediate returns.
Forests, for example, are valued for their timber. When a country needs money, the forests can be cut down and the capital immediately released.
This may contribute to the nation's Gross Domestic Product, but in reality, the country has lost resources and becomes poorer.
The rationale for preserving wildlife is based on a variety of societal values including aesthetic, moral and spiritual ones, as well as more practical ones, such as contributing to the economy and human livelihoods.
It is also based on a precautionary approach and, in my view, common sense. If a species is there, I am firmly convinced that it has a good reason to be.
Nature has developed over millions of years to produce the most favourable environment for us to live in. Before attempting to disturb the subtle balance on which we all depend, with unknown consequences, we should look carefully at what we have and know.
In fact, we still know very little of the diversity of life on our planet, but we know enough to get a global view of what is happening.
Almost a century ago, some "visionaries" sounded the first alarm bells. They have long been called "alarmists" but their predictions have slowly become reality.
Even today, when you tell the truth about the environment, many will deny the facts and try to block action; this will inevitably result in a bigger problem in the future.
Out of focus
We spend enormous energy and lose precious time by trying to demonstrate the obvious: wildlife in its integrity is vital for us.
Instead, those who do not believe that, or think human ingenuity will solve all our problems, should be asked to demonstrate that they can live without nature.
For a very long time, conservationists have been portrayed as misanthropists, caring more for animals than other human beings. But human rights and preservation of the environment are complementary.
The environment should always be a key pillar of development aid. Humans and nature go hand in hand.
Nowadays, when the spectrum of an economic recession is looming in various part of the world, the fact that nature can sustain humankind freely is not the least of its benefits, especially for the world's poor.
There is increasing recognition of the services nature provides to us, such as clean water and healthy soils for growing crops. But considering the competition between wild species and humans on a very crowded planet, one can ask if there is there room for both of us?
There is no doubt that nature can survive without humans - and has done so, for the most part, since time began.
Humans surviving without nature is certainly not true so we have no choice but to find enough space for nature.
Despite the very limited knowledge of life on Earth, some people do not hesitate to claim that some species have no interest to humans, that we should sort them out and get rid of "redundant" species and eliminate "pests".
So should nature be preserved in its entirety, meaning all species? I say yes, without any hesitation.
Not a luxury
Almost all countries agreed at the 2002 World Summit on Sustainable Development in Johannesburg, South Africa, or through the Convention on Biological Diversity, that we should significantly reduce biodiversity loss as a means to fight poverty.
Every day there is a stronger consensus that, without preserving nature, the Millennium Development Goals to eradicate hunger and poverty, provide education, or combat diseases, cannot be achieved.
This is, for me, a clear response. Nature is not a luxury; it should be preserved at all costs. However, we are still losing species, as shown by the IUCN Red List of Threatened Species.
While many are not extinct yet, the Red List shows that many are slipping slowly towards extinction. We are witnessing a collective failure to meet these agreed goals.
In parallel, the good news is that we are documenting more and more conservation successes. It shows that a clear understanding of the problems and taking appropriate collective actions, nature can be preserved.
Increasingly, human overpopulation is recognised as the biggest challenge. The need to feed this growing population is increasing the pressure on nature.
Decisions will continue to be taken in a context of emergency and without appropriate thinking or incorporation of environmental considerations, as has been the case with the uncontrolled development of biofuels.
Our ability to live with nature can also be questioned. We hear that there are too many whales depleting fish stocks, too many elephants destroying farmers' plantations, too many tigers or sharks killing people, too many wolves eating sheep, too many mosquitoes transmitting diseases, too many frogs making noises, too many trees spreading leaves in our gardens; the list could go on forever.
Quantity and quality
The positive side of this is that we still have species to fight against. Once gone, will there be anyone else other than our neighbours to fight with?
Species abundance is also important. We need large quantities of fish if we want to feed the world. We need enough pollinators and soil invertebrates to maintain food production.
We need a healthy population of prey to maintain predator populations. We need a large numbers of wildebeests in the Serengeti to attract tourists and ensure the fertilisation of the savannah.
The same applies to salmon, whose spawning migration is the basis of an entire food chain. Massive animal migrations or congregations of spectacular animals are the guarantee that tourists will see what they have paid to come and watch.
We need enough predators to control herbivore populations; Olive Ridley turtles ensure reproductive success by swarming beaches in mass to lay their eggs.
Wildlife is not just a question of diversity but also of quantity. The collapse of cod stocks in the northern Atlantic is the perfect illustration; cod can still be found but, for unknown reasons, the stock was never able to recover and can no longer sustain an economy.
In 2050 the human population will stand at more than nine billion, with an increased demand for goods, so what does sustainable development really mean?
Can it be achieved without drastic changes? Do we want nature to be confined in zoos and botanic gardens or isolated pockets where rich tourists could go and watch what once covered most of our planet?
Global changes and new emerging threats will not allow us to maintain this static model. Climate change, invasive species and diseases do not stop at the borders of national parks. The risk cannot continue to be evaluated by our decision-makers in terms of success at the next election.
Fortunately, it seems that showing a real commitment to the preservation of our planet is starting to pay off in political terms.
A return to more spiritual values and the findings of a study on the economics of ecosystems and biodiversity might bring the key additional elements needed for a real push in favour of the preservation of the diversity of life and, more broadly, all forms of diversity on our generous planet.
Jean-Christophe Vie is deputy chairman of the IUCN's Species Survival Group, and author of the book Le Jour au L'Abeille Disparaitra...
The Green Room is a series of opinion articles on environmental topics running weekly on the BBC News website
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