The Importance of Biodiversity,
Ce commentaire est de: Diversity Of Life (Paperback)
The author of "The Diversity of Life," Edward O. Wilson, is passionate and excited about his topic and writes poetically and effectively about the natural world. The first section of the book finds him in the rain forest of the Brazilian Amazon, pondering one of his favorite puzzles: why some species dominate and spread while others become rare. A huge storm arises, violent and destructive. But the life in the rainforest has adapted to these events of nature. If some species are destroyed, others rush in to fill the void because of the diversity of nature. Edward O. Wilson's intent in writing this book is to convince people that biodiversity and environmental concerns are of benefit to mankind, not only for reasons of preservation but for economic reasons. He shows how life can endlessly recreate itself, if allowed to do so.
As illustration of his thesis, the author discusses the island of Krakatau, near Sumatra, that was completely destroyed by a volcano in 1883. Tidal waves resulted, killing 40,000 people in Java and Sumatra. The rock and debris blew high in the air, and a residue of dust diffused around the world, producing bright red sunsets. A remnant of Krakatau remained at what had been the southern end of the island, totally barren. But, starting with a single spider, forms of life returned and took hold until, today, you would never guess the violent past of the island. Wilson uses this as a vivid illustration of how nature at its most violent doesn't destroy life.
The author emphasizes the importance of the tropical rain forest. It occupies only 6% of land surface but probably harbors more than half of the species on earth. Its abundant solar energy, evenness of climate and largeness of area account for this, and also enough evolutionary time. The smaller the species, the more abundant it is. The human species came on the scene late and, when they did, everything changed.
The author describes how the coming of man to different locales destroys many species. For instance, in the Hawaiian Islands, the Polynesians ate man of the birds until only a handful of species remain. In western North America, the earliest Americans, the Paleo Indians, caused the diversity of mammoths to collapse because they needed food and hunted the different species to extinction.
Some experts think climactic change accounts for a decline of a species, while others favor overkill by humans. The author sides with the latter group. Overkill, habitat destruction, and the introduction of exotic species that don't belong in an environment are all acts of man. Conservationists now know that entire habitats must be preserved to save particular species. The author lists and describes 18 ecosytems that deserve the immediate attention of conservationists. Global warming is also a threat to species, but human activity has increased extinction by many thousands of times than that which would occur without humans.
Biodiversity is a valuable resource (new sources of food, new cures for cancer may perhaps be found among diverse species). The new approach to environmentalism is to tr to draw more income from wildlands without killing them. What we try to save now in ecosystems isn't just individual species. The author lists plants and fungi that yield pharmaceutical products and also ones that are sources of new foods to show the importance of maintaining biodiversity. He goes on to make a list of animals that are not currently eaten that make good protein sources. Both conservation and economic growth can be served by preserving natural ecosystems.
The author concludes the book with suggestions for saving our biological resources. First, he suggests that surveys be taken of the world's flora and fauna. Next, create biological wealth by finding out what uses can be made of the species inventoried. Promote sustainable development. In very poor countries, help the people find ways to survive economically without plundering their environment. This will require education and social change. Finally, save what remains. Save as much biodiversity as possible and make the reserves as large as possible. Edward O. Wilson realizes that mankind is much more likely to follow its economic interests than it is to selflessly protect the environment. Therefore, he very cleverly appeals to this self-interest by making biodiversity appear to be of economic benefit.