Securing the fabric of life

Our planet is, so far as we know, the only asteroid in the universe to feature life. And it is life in forms so abundant that we have next to no idea how abundant it is. We send costly space probes to Mars to see if there ever was life there, and if we found anything it would almost certainly be a primitive slime mould or something equally rudimentary. Yet here on Earth we have millions of species that are so advanced that we have little grasp of just how advanced they are.

Yes, millions of them. But how many millions? Nobody has more than a vague clue. Estimates range from 7 million to 100 million, with 'informed estimates' centring on 8-15 million. It is a scandal of modern science that we do not know within an order of magnitude how numerous and multiformed is this super-exceptional phenomenon.

Frog, Costa Rica
© Bermingham and Isenhart/Conservation International

In physics we can measure the distance from the Earth to the Moon with an accuracy of half a centimetre. By comparison, the science of biodiversity is still in its Stone Age. So far, we have identified 1.7 million species, and if we keep up our cataloguing at the present rate it will take us several decades to list even half of the species that share this planet with us (and supposing they do not have the extravagance to exceed 10 million).

Environmental services

Despite our grandscale indifference to species and their numbers, we benefit from the many environmental services they supply to us, and do it free. These services range from creation of soil, supply of water, and natural controls of pests, to dispersal of pollutants, functions of watersheds, and stability of weather and climate, to cite but the most obvious items.

Until just recently, these services carried no specific economic values since nobody had bothered to take a crack at estimating them. Result: political leaders and policy-makers effectively marked them down as trifling if not nil. Fortunately David Pimentel and his colleagues at Cornell University have come up with an estimate which, while preliminary and approximate, puts the worldwide total at $2.9 trillion per year. To put proportion on the figure, consider that it is twice as large as Britain's economy.

Another team of analysts, this time put together by Robert Constanza at the University of Maryland, has come up with a more expansive estimate - still exploratory but illuminating insofar as it helps us to get a handle on what is at stake in biodiversity: $33 trillion per year, by contrast with the world's economy of $29 trillion. So global natural product is greater than global economic product.

But, some might say, how does this planetary arithmetic translate into better protection for biodiversity on the ground? Consider the many medicines and drugs bestowed by wild plants. The American pharmaceutical giant, Eli Lilley, exploited two biocompounds in the rosy periwinkle to manufacture vincristine and vinblastine, potent therapies against blood cancers. They save 30,000 American lives a year, and sales of the two drugs are worth a whopping half billion dollars a year worldwide.

Encouraged by these commercial successes, another American pharmaceutical company, Merck, has paid more than $1 million to Costa Rica for "bioprospecting" rights in Costa Rica's forests, and it will hand over a percentage of sales revenues if ever its search produces a plant-derived drug. So Costa Rica is making money out of its species through medicine alone, using the funds to help its conservation activities. Lots of other countries are taking note.

The Rosy Periwinkle contains cancer-curing properties
© Kevin Schafer/Still Pictures

Then there are the revenues to be gained from ecotourism, dependent as it is on wildlife and biodiversity. People taking nature-related trips contribute at least $200 billion each year to the national economies of the countries they visit. In 1994, whale watching in 65 countries attracted 5.4 million viewers and generated tourism revenues of $504 million. According to conservative estimates, a pod (group) of sixteen whales at Agate in Japan would earn at least $41 million from whale watchers over the next 15 years, whereas if whalers killed them their carcasses would be worth only $4.3 million. As far back as 1970, ecotourism in Costa Rica's Monteverde Cloud Forest Reserve generated revenues of $4.5 million or $1,250 per hectare, whereas farmland outside the Reserve was earning only $100-300 per hectare.

Mass extinction

Despite these findings, we keep on rending the fabric of life in every part of the planet. There are many signs that we are well into a mass extinction of species and populations alike. Within the lifetimes of many readers of this magazine, and supposing we allow the extinction spasm to proceed unopposed, we could well be saying goodbye to half of what we like to call our fellow species. That would put the extinction episode on a par with the "great dying" of the dinosaurs and associated species 65 million years ago, and make it the sixth mass extinction since the first flickerings of modern life 650 million years back.

What we do, or don't do, during the next few decades will determine the outcome of this momentous moment in evolutionary time. Our decision will be the biggest of its kind taken by any human community. We have it in our hands to determine the future of the biosphere for the next five million years, this being the length of time it generally takes evolution to come up with a stock of replacement species with numbers and variety to match what was there before. Five million years is twenty times longer than humans have been a species themselves.

In fact, we may have less than a "few decades" to pull the action levers and get on top of the problem before it gets on top of us. How about two decades at most? To slow and stem the processes of habitat destruction, let alone to halt or even reverse them, cannot be done overnight.

A Kubu tribesman surveys the effect of a forest fire, Indonesia
� Mark Edwards/Still Pictures

Much the same applies to other problems. Eroded topsoil cannot be restored within less than a century, yet we keep on doing away with the stuff with ever-greater energy and ingenuity. We could push back the deserts, but it will probably take us a good century to do it. To restabilise climate in a globally warmed world could well take several centuries. All these "environmental insults" will take a heavy toll on wildlands (forests, savannahs, coral reefs and the lengthy like), hence of the habitats of species in their millions. Slowing and stopping the damage will be like turning around a supertanker at sea. When the captain decides on the major "policy change", it will take him a chunk of time to slow his ship and a longer chunk to actually turn it.

Suppose we could manage the corrective shifts within just two decades - and if we can't manage it in that time, we shall surely find the destructive processes will have worked up so much momentum that we shall be on board the equivalent of a runaway tanker. Two decades is 7,300 days. This means that we lose one per cent of our manoeuvring room every ten weeks.

At the same time of course we can do much by way of a holding action through establishing more protected areas. But protected areas protect habitats against something, and that "something" is growing bigger every day and faster than ever.

We could designate the whole of Amazonia as one huge national park, and to keep out landless farmers (who torch the forest merely as a means to get supper on the table) we could build a perimeter fence 50 metres high (though that would take a lot of timber). Our fence would still not keep out global warming, which may one day wreak extreme injury on tropical forests. We may eventually find, indeed, that the burners of fossil fuels (the main source of carbon dioxide emissions) cause more species extinctions than the direct burners of the forests.

Protecting habitats

In short, the strategy of creating protected areas that has served us well for decades, can no longer deliver on its own. In any case, many protected areas may not survive in the long run. Sure, we need them more than ever as an immediate measure. But let's face it: they respond to symptoms of the basic problem, rather than tackling sources of the problem.

Of course the prime way to tackle the Great Threat is to slow the growth in human numbers and the growth in human demands. That's a story familiar enough to readers of this magazine, and it's a tough tale over the long haul. But a more positive reaction right now is to reflect that what we primarily do to save biodiversity, protecting habitats, will bring us further benefits of all sorts on all sides.

Giant Panda with her one-month-old baby, Wolong Nature Reserve, China. � Susan A Mainka/WWF-Canon

Apart from setting up more protected areas, we need to push back the deserts, replant the forests, stop soil erosion, clean up acid rain, restore the ozone layer, stabilise climate, and the lengthy like. Unless we do these things, we shall effectively be saying goodbye to millions of species - and leaving a planetary habitat for ourselves that will be grossly degraded.

So - and here's the splendid payoff - we need to do all these conservationist things for all kinds of other reasons apart from saving species. In other words, we have reached a stage where, essentially, we can save species only by saving the biosphere. If we allow entire segments of the biosphere to head off into terminal trouble (for instance, we may lose virtually all tropical forests within just a few decades), what will it avail us to have established lots more networks of parks?

The challenges are superscale. They all add up to one true question. Do we really want to save species, those millions of fellow species to which are saying there is not room on Planet Earth for us and them? To cite the Spice Girls, do we know what we really, really want?

Professor Norman Myers is an award-winning environmental scientist and author of 17 books on environmental issues, including forests and biodiversity. A Visiting Fellow of Green College, Oxford, he pioneered the concept of biodiversity hotspots and has produced ground-breaking studies on environmental security and perverse subsidies.

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