OCR Text |
Show WHAT DIFFERENCE DOES IT MAKE? As humans recklessly cause the extinction of other plant and animal species, we may be hastening the day of our own. By Jim Stiles What has evolved on our planet is beings with a great intelligence, with actions, with the ability even to leave it would be if, after four billion years not just life, not just grass or beetles or mice or microbes, but a capacity to anticipate the future consequences of present their home world and seek out life elsewhere. What a waste of torturous evolution, the dominant organism on the planet contrived its own annihilation. No species is guaranteed tenure on this planet. And we've been here for only about a million years, we, the first species that has devised the means for its own selfdestruction. Carl Sagan As the biologist Tim Flannery observes, what humans have become, in many ways, is an exotic species, like Russian thistle or the tamarisk tree in the United States. Introduced to an environment where there were no natural barriers or limiting factors, Russian thistle and tamarisk grew unchecked across the American West. Likewise, humans have come to have a similar impact on the entire planet. We have actually been able to affect its biophysical features and there are no "limiting factors" out there to slow us down. To make matters worse, even when we can see the devastating effects of our actions on the ecosystem, we often choose the more than approaching the challenge with any real solutions when it requires a sacrifice fear more than sacrifice. That is why, On Easter Sunday, April 5, 1722, Jakob Roggeveen spotted a tiny island, 2000 miles west of the Chilean coast. captain of Afrikaansche morning the Earth Summit in 1992. But even in terms of long-term the next economic health, how can we do was Dutch Galei, and he investigate. moved The to levels that Canada agreed to at ship Roggeveen the politically expedient short-term "solution," rather degree of honesty or vision. We particularly avoid from the people. There is no word that politicians in 1995, the United States refused to act on commitments to reduce the nation’s carbon dioxide emissions closer to that? How can we ignore the scientific evidence? Author David Suzuki describes the work of Peter captain organized a small group of men to go ashore and what they discovered on this barren windswept island astonished them. High above the scattered along the Vitousek, a Stanford University biologist. Vitousek and _ his associates “calculated the total amount of the planet’s primary shore, grassy ridgeline were dozens of huge productivity, used directly or intricately carved stone sculptures, some as tall as thirty feet. The Dutch had not expected to find a culture on this remote island with the skills to create such works of art. Nor could they understand how the statues were transported there, for the island indirectly by our species. His calculation’ includes not only was one species out of perhaps 10 million to 30 million is co-opting almost 40% of the Earth's primary productivity, and. what we exploit is denied to other species. In another fifty years, our utterly devoid of emissions, on. were non-existent. It remained a for centuries and untold numbers of { theories about their origin. Barely 25 years ago, the writer Erik von Daniken speculated in his book The Chariots of the Gods that the stone monoliths on Easter Island were the work of extraterrestrial beings. His theory was embraced by millions who could see no other explanation. And it was about as believable as anyone else’s theories. But the truth lay under the rim of an extinct volcano crater where scientists discovered a sequence of preserved pollen. It proved that Easter Island had once been like many other Pacific islands in that temperate location. The toromiro tree, a common source for rope by humans throughout Polynesia, was dominant on Easter Island, as was the Chilean wine palm, the largest palm tree in the world. It grows to a diameter of three feet or more and as tall as sixty feet. He astonishing trees. Course grasses covered the island and woody plants of any size mystery generated forests logged, grasslands paved over or grazed over by domestic animals, and so came figure up with of 38.8% the So numbers could double again. Will we then demand twice as much of the primary productivity of the world?" And we may find ourselves From a painting by John Depuy causing the extinction of species we don’t yet know exist. Edward O. Wilson, from Harvard University, points out that while science has identified about 1.4 million species, the actual number may run as high as 100 million. There are 69,000 known species of fungi; yet there are estimated to be 1.6 million. Or consider arthropods, including most insects, which could number as high as 8 to 10 million just in the world’s tropical rainforests. But we may never identify them. By studying the fossil record, Wilson concludes that we are reducing the number of species on Earth "by a rate of 1000 to 10,000 times higher than existed in pre-human times." We are currently destroying 1.8% of our tropical rainforest every year, home to more than half of all the species on Earth. Every year! Wilson predicts, "Unchecked, 20% or more of the earth’s species will disappear or be consigned to This lush forested island is what awaited the Rapanui culture when they first settled there near the end of the first millennium. The Rapanui were great artists and builders and they made quick use of the big trees---the Chilean palms especially made perfect rollers for transporting the great stone statues and for the construction of homes and buildings. early extinction during the next thirty years. From prehistory to the present time, humanity has probably already eliminated 10 or even 20 percent of the species.” But the Rapanui were terrible stewards of the land. At the height of their culture, the population reached as high as 8000. But by the end of the 14th Century, the trees were Stuart Pimm, a conservation biologist from the University of Tennessee, has an almost apocalyptic view of the future. He and his colleagues believe that as much as 50% of the gone. As the Chilean palms and toromiro trees were cut down, the soil eroded rapidly and became too poor to grow anything but the grasses that eventually dominated the island. By 1650, the island could no longer support its population and the Rapanui suffered for centuries, living in caves and barely eking out enough food from the depleted land to survive. By the time of Roggeveen’s visit, about 2000 still lived on Easter Island. By 1877, only 111 Rapanui remained. They found themselves completely isolated from the rest of the world. The Rapanui no longer even possessed the raw materials to escape the prison they had created. for themselves. They could not even build a simple canoe. Easter Island was the world to the Rapanui and within that world, the reckless destruction of the Chilean wine palms and the toromiro trees brought about their own demise. These people possessed remarkable artistic skills and the artifacts of their culture suggest a highly sophisticated society in so many ways; yet the Rapanui’s careless regard for the natural world around them contributed directly to their own near extinction. Clearly, humans have been imposing their destructive will on this planet for thousands of years and with devastating effects. But that impulse to destroy has been exponentially amplified by our own expanding technology and by our sheer numbers. A century ago the Earth’s human population stood at just under one billion. This year, it approaches six billion, with no real end to the unlimited growth in sight. As the numbers swell, too many of us think that technology will save our species and the rest of the planet from what sometimes seems like certain annihilation. But it may do just the opposite. world’s flora and fauna could be facing extinction within the next century, Pimm estimates that 11% of all birds on the planet face the threat of immediate extinction. Pimm says, "It’s not just species on islands or in rain forests or just birds or big charismatic animals. It’s everything and it’s everywhere...It is a world-wide epidemic of extinctions." But so what? What if some weird little tree frog in the Amazon rain forest becomes extinct. Who will know? Who will care? What difference will it make? It can make a difference to all of us. According to Edward Wilson again, "The vast material wealth (of our natural resources) is at risk. Wild species are an untapped source of new pharmaceuticals, crops, fibers, pulp, petroleum substitutes, and agents for the restoration of soil and water.” Sir Ghillean Prance, the director of the Royal Botanic Gardens at Kew in London notes, “Every time we lose a species, we lose an option for the future. We lose a potential cure for AIDS or a virus-resistant crop. So we must somehow stop losing species, not just for the sake of our planet but for our own selfish needs and uses." Our future will always depend on the health and diversity of our ecosystem, what David Suzuki describes as the "complex community of exquisitely interconnected, diverse organisms that are finely tuned to live in balance with the physical supports of the air, water, soil, and climate of the area. Honed by billions of years of evolution, nature has the resilience to survive the vast environmental upheavals that have occurred throughout time." |