Ross Cameron
Left orthodoxy maintains that the story of man's interaction with the ecosphere is a story of habitat degradation leading to species extinction. That's the headline. But by overstating the risks of climate change, and underestimating the capacity of humans and other species to adapt, we risk missing the chance to address real, pressing, soluble environmental problems.
Scientists at James Cook University last week announced they have discovered an exquisite new species of pygmy seahorse, 200 kilometres off the coast of Cairns. At less than half a centimetre long, the tiny creature may be the smallest vertebrate.
The discovery adds to the work of 2700 scientists from 80 countries who just completed the first Census of Marine Life. The census increased the estimate of known species from 230,000 to 250,000, finding ''an unanticipated riot of species, which are the currency of diversity''.
Advertisement: Story continues below A startling find is the ''rare biosphere'' of microbes - species surviving in numbers of less than one in 10,000. These tiny cohorts subsist among masses of a dominant competitor, apparently waiting and hoping that conditions will change to allow their moment on the evolutionary stage. They seem to be a planetary insurance policy so that even if nutrient or temperature conditions change over time, there will still be an abundance of microscopic sea life in the food chain.
Outbreaks of the crown of thorns starfish on the Great Barrier Reef have reduced by half over the past decade. Scientists have no way of explaining their pattern of aggression and regression but it is clear that runoff from the farmers of north Queensland is not the main culprit.
Our lack of perspective derives in part from shortness of memory. It is not possible to recall the five mass extinction events that have, independent of man, wiped out more than 90 per cent of all species that ever lived - only to be followed, in each case, by an explosion of new life. Virtually no large land animals survived the end Cretaceous mass extinction 65 million years ago. As global temperatures rose six to 14 degrees higher than current levels, most plants and tropical marine life were decimated but all life on earth today is descended from the 10 to 15 per cent of species that survived that terrible wipeout.
The alarmist claims of eco-warriors such as Al Gore have suggested melting polar ice caps will cause sea levels to rise by seven metres over the next century, with catastrophic results for coastal cities globally. The best guess of the United Nations climate panel says that sea levels will not rise more than half a metre in that period. The climate economist Richard Tol has shown that rising temperatures would actually deliver a range of benefits to the planet and to mankind, including reduced energy costs for many. For most of earth's 4.5 billion year history, life has developed most quickly, with the greatest diversity, in periods without ice caps.
Life on land continues to prove highly adaptable, too. For some time it was illegal to feed native birds in NSW. The authorities in Sydney realised that prohibiting feeding was simply removing birds from the cityscape and repressing a natural behaviour in humans. Recently, they relented. The lorikeets and kookaburras are back on balconies of Meriton Apartments, eating seed meal from Woolworths. It is no Arcadian idyll but it is successful adaptation.
Meanwhile, the government of China is taking responsibility for groundwater salinity and urban pollution with a determination that no other country could contemplate. Tokyo has adapted to man-induced subsidence of four metres over the past 70 years. Ingenious Dutch dykes and barrages have made habitable and productive a country with one-fifth of its landmass below sea level. Professor Bjorn Lomborg estimates that further adaptation to sea level rises over the next century will cost one-tenth of 1 per cent of Holland's gross domestic product.
This year's inundation has let the mouth of the Murray River spring back to life with death-defying audacity. Inflows in October were the highest in a decade. Shellfish middens dotting the dunes attest that this special place has sustained human and marine life throughout droughts and floods for 30,000 years.
While we obsess about a global price for carbon (without which there would be no life at all), we risk failing to respond adequately to soluble problems like why marine mammals beach or how to repel the European carp from Australian rivers and arrest the southern march of the cane toad. We can and must tackle the boring but important challenges of noxious weeds and feral cats. All are responsive to effort, ingenuity and leadership.
Humankind must be accountable for its ability to affect the quality of life of all species on the planet we share but let's admit it is not possible for 6 billion humans to live anywhere in a ''steady state''. Nature doesn't. We mustn't get depressed by the hellfire gloom of those trying to scare us into submission. The story of life on earth is one of stunning resilience, abundance and diversity.
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