CFACT Briefing Paper #102
From movies to classrooms to the nightly news, Americans are constantly being told that of the world’s environmental “crises,” the staggering loss of tropical rainforest, and Amazon rainforest in particular, is right up there at the top. Pictures of charred remains of once lush jungles flicker before our eyes, we are shown the exotic plants and wild species that are being made homeless by the chainsaw and the flame, and numbers likened to one football field per second are used to describe this devastating loss. As a result of this, we are told that the tropical rainforests will all soon disappear, that nearly half of all the species on planet earth will soon be extinguished, and that these areas must be basically put off limits to humankind if we have any hope of saving this wonderful miracle of nature. With an emphasis on the Amazon region, the following paper provides some background on tropical rainforests, examines the truth about deforestation rates and the species extinctions that are said to follow, and compares two very differing views about the relationship between people and nature in the tropics.
The word “rainforest” was coined in 1898 by a German botanist to describe forests that grow in constantly wet conditions, with an average annual rainfall of 80 inches per year or more. There are differing kinds of rainforest including “flooded mangrove forests along the salty coastline of SE Asian islands, high-altitude cloud forests of S. American, temperate rain forests of the U.S. Pacific Northwest,” and the “tropical rain forests that form large pockets of green along the earth’s equator” — the major focus of this paper. Tropical “rainforests grow in more than 50 countries but about half of the total is in just three: Brazil with 33%, and Zaire and Indonesia with 10% each,” and 57% of total is in Latin America. (National Wildlife Federation – Educator’s Guide)
Tropical rainforests are found within the tropics of Cancer and Capricorn, in a belt that girdles the earth. Location is between 23 1/2 degrees north and 23 1/2 south of the equator. They grow through the heart of South America, Africa, Northern Australia, Malaysia, Indonesia, and the Philippines, to name a few. (Lessons of the Rainforest, Donald Perry, p.26)
Tropical forests today cover about 13% of earth’s surface (others say only 7%). Amazon covers 6.5 million square kilometers, of which 3.5 million is in Brazil. “Brazil has created what is known as Legal Amazonia which covers nearly 5 million square kilometers, or 57 percent of Brazil’s territory. The entire continent of Europe could fit inside Legal Amazonia, and 70 percent of it is tropical forest.” (The Cross and the Rainforest, p.146)
Within the Americas, tropical rainforests are located in five main regions: Mexico and Central America (known as Mesoamerica), Pacific Coastal Columbia and Ecuador (known as the Choco which extends from the Panama border south to northern Ecuador, is the wettest region in the world, and in terms of biological diversity is thought to be one of the most important in the world), the Caribbean Islands, the Guianas and Amazonia (which contain the largest contiguous rainforest in the world including part of eight countries — Bolivia, Brazil, Columbia, French Guiana, Guyana, Peru, Suriname and Venezuela – app. 7 million square kilometers), and finally, Atlantic Coastal Brazil. (Lessons from the Rainforest, Ghillean Prance, pp. 53-54).
Early explorers to Brazil and Zaire were probably the first to use the word “jungle” because as they traveled through on boats, riverbanks were tangled with vegetation and they thought the interior was probably that way too. But the edges have thicker plant growth because of extra light. Interior is made of trees, shrubs, vines, ferns and other plants “growing to form a complex system of layers.” (NWF – Educator’s Guide)
There are three main characteristics of the tropical rainforests. First, is lush vegetation with dense, closed forests and high canopies that allow little light to reach the ground. Second is rich flora and several endemic species. Third is stratification. (“Environmental Gore,” Evaristo de Miranda, p.154)
On top is the emergent layer of giant trees, growing to heights of 115 to 250 feet. Only one or two emergents per acre usually, and have small leaves, umbrella shaped crowns and tall, slender trunks.
Next is canopy layer at 65 to 100 feet formed by flat-crowned trees that offer near-continuous cover over the forest. Catch most of the sun’s rays, allowing only 2 to 5 percent to slip through to forest floor.
Below this is understory of trees that usually don’t grow higher than 15 feet or so along with young canopy trees and shrubs. Many have large leaves that may help absorb light in dim understory.
On forest floor, air is very still, humidity is almost always above 70%, and temperature is relatively constant and other than seedlings, herbs, and ferns, vegetation is sparse due to lack of light. Also, mostly free from decaying logs and dead leaves since high temps and humidity are good place for billions of microorganisms in soil to break down debris quickly. “This fast and continual recycling of nutrients is what keeps rainforest systems working so efficiently, despite their shallow, relatively infertile soil.” (NWF-Educator’s Guide)
According to one study, 75% of the nutrients found in rain forests is located in the plants, 17% is in decomposing matter, and only 8% is in the soil itself. Therefore, they have developed as closed systems where “anatomical, physiological, biochemical, and ecological mechanisms…guarantee little loss, little uptake from the sources, and thus, conservation of nutrients.” (deMiranda – p.155)
The benefits of the rainforest First and foremost, tropical rainforests “are home to a vast biological array of living organisms…and support more plant and animal species per unit area, as well as overall, than any other ecosystem on earth.” Current estimates of the total number of living species on the planet range from five to 30 million or more, of which only 1.4 million have been described by scientists. More than two-thirds of these species come from tropical rain forests, basically because the forest are home to the most species-rich groups in the world — anthropods and flowering plants.
Peru, for instance, is home to around 30,000 species of plants; Columbia, a country as big as New Mexico and Texas combined, has more than 1,550 bird species (twice the number round in North America); a single river in Brazil harbors more species of fish than all the rivers in the U.S….A world record was established in 1988 by Alwyn H. Gentry who identified about 300 tree species in each of two one-hectare (2.47 acres/hectare) plots in Iquitos, Peru.” (de Miranda, pp. 155-156).
â€œThe Amazon River drainage basin alone supports about 5,000 kinds of fishes, nearly equal to all those in the Atlantic Ocean, while little Panama boasts as many plant species as the entire continent of Europe.” (Richard Nalley, Science Digest, p.56)
“Tropical rainforests are also important because they supply a great variety of commercial and noncommercial products: timber (some highly prized woods such as teak, mahogany, and rosewood), fuel wood, fruits, vegetables, nuts and spices, medicines (a quarter of all medically-active substances come from tropical plants [including treatment for childhood leukemia], and…around 70% of the 3,000 plants identified by the U.S. National Cancer Institute as having anti-cancer properties are tropical rain forest species.” (de Miranda p.156)
The rainforest provides a virtual pantry of goods commonly used including canes and fibers like bamboo, rattan, and jute (for rope, twine and burlap), fruits and veggies like avocados, bananas, mangos, papaya, passion fruit, and pineapple, spices and flavors including allspice, pepper, nutmeg, cinnamon, vanilla, paprika, cloves, and ginger, oils like camphor, coconut, sandalwood, and palm, medicines like curare, ipecac, and quinine, and a host of other things like Brazil nuts, cashews, and tea. (NWF Educator’s Guide, P.17)
Other products like sugar, peanuts, and sesame seeds are thought to have their origin in tropical habitats, and for products like corn, rice and bananas, tropical forests “offer genetic improvements of several major crops…In 1970 the U.S. corn crop was hit with a blight that destroyed half the crop in many areas. The costs amounted to $2 billion in one year…[but] the crisis was remedied through interbreeding an immune form of corn that originally derived from the ancestral home of corn, Mexico.”
There are several other products that have a crucial link to the tropical forests. One is chewing gum which comes from the chicle tree. Another is rubber which comes from rubber trees and is used for commercial and industrial purposes around the world including balloons, erasers, globes, tires, hoses and shoes. Yet another is coffee which comes “courtesy of a bush in Ethiopia’s forest. Being the ancestral source of all coffee plantations throughout the tropics, this wild bush continues to supply germplasm material to boost coffee productivity and to resist diseases.” The other is chocolate which “originally derives from the cocoa tree native to western Amazonia and the Pacific coast of Ecuador.” (Lessons, Norman Myers, pp. 16-18)
Finally, some of the richest ore bodies are found in the Amazon including iron, manganese, cassiterite, bauxite, gold, copper and nickel. And there is also great hydroelectric potential in the area with 45% of Brazil’s hydro potential in the Amazon basin. (de Miranda, p.159)
[Side note: One last area of benefit of tropical rainforests often cited concerns its natural impact on climate and flood and erosion control. Forests obviously have a great influence on holding soil in place. Forests also have “sponge effect” that act to soak up some rain and prevent flooding during heavy rain season. But further, Myers (and others) argue that as the green band around the equator becomes more “bald,” there will be an increase in the “shininess” or reflectivity of the earth’s surface, causing an “albedo effect” that could influence convection currents, wind patters, and rainfall regimes throughout the tropical zone. The other area is global warming (fossil fuel emissions account for 5 billion tons of carbon annually while forest burning allegedly accounts for 2 billion). But this is a topic for another day since there are many, many serious questions about the whole premise of global warming. Finally is talk about the rainforests supposedly being the “lungs” of the planet, even though 70% of our oxygen is thought to come from algae.]
Some History on Development
“From its mountains you may dig silver, iron, coal, copper, quicksilver, zinc and tin; from the sands of its tributaries you may wash gold, diamonds and precious stones; from its forests you may gather drugs of virtues the most rare, spices of aroma the most exquisite, gums and resins of the most useful properties, dyes of hues the most brilliant, with cabinet and building woods of finest polish and most enduring texture. Its climate is everlasting summer, and its harvests perennial.” Matthew Maury, Amazon booster, 1850’s
“Europe and its children, the white-skinned cultures of the temperate zone, began to confront the tropical world more than five hundred years ago, driven by a craving for profits. Commercial capitalism spread worldwide from northwestern Europe, promoted by gunboats and colonial bureaucrats.” (Lessons, Richard P. Tucker, pp. 39-40)
With so much to offer in the way of valuable natural resources, the rainforests of the world have long been objects of interest to those looking to take advantage of their storehouses of wealth. Many would view this as good and noble, with men trying to make their lives and the lives of people around them better through the creation of jobs, new and useful products, and increased economic growth and prosperity.
But for most environmentalists currently writing on the subject, the story of man’s impact on the rainforest is nothing but one of exploitation. Tucker tells of how in SE Asia, the extraction of spices, woods and other products were done for 300 years without hurting the forest ecosystem. And in Africa, only small amounts of hardwood and oil palm nuts were harvested. But in the America’s there was a different fate. “Some New World forests were entirely eliminated by plantation agriculture before the French Revolution transformed Europe’s colonial regimes. The agent was sugar, the first widespread tropical monocrop….The Portuguese, taking control of coastal Brazil after 1530, leveled a long forest belt, replacing it with sugar plantations.” These sugar plantations were later moved to Caribbean islands. And besides sugar, hardwood timber was the other early-modern rainforest export.
From the 1830’s onward, coffee became a key Latin American export and took over much land in Brazil, Columbia, and Central America. By the mid to late 1800’s, rubber and the search for unclaimed swaths of rubber trees had sent prospectors through more than 11,000 waterways making up the Amazon since the process of rubber vulcanization was discovered around that time. Soon after, there was a rubber boom in the region. But by 1910, there was a crash in the Amazon market as lower cost-rubber tree plantations were set up in tropical Asia. Henry Ford actually established a million-acre rubber plantation in Brazil, “Fordlandia,” — the first large-scale monoculture plantation in Amazonia. But it failed for two ecological factors: the use of a floodplain forest species on the upland terra firma and a leaf rust fungus that attacked the leaves. In the tropics, there is usually a considerable distance between trees of the same species, probably as a defense against diseases and pests afflicting species that grow together. But Fordlandia tried to buck this and lost. (Lessons, Prance, pp. 59-60)
“Tropical fruit plantations followed sugar as the conquerors of lowland moist forests… and by the 1950’s tropical governments and multinational corporations were competing for control over natural resource systems” Tropical timber industry also had massive acceleration after 1950. What made a lot of this possible were new bulldozers and gas-powered logging trucks that could now penetrate deeper into forest and provide far more timber. (Tucker, pp. 42-49)
One story that for many symbolizes the quest for wealth in the Amazon is the legend of the Golden King, El Dorado. “In its original form, it referred to a king with wealth so vast that each day he was anointed with precious resins to fix the gold dust decorating his body. The chronicler Oviedo recounts how the famous conquistador Pizarro who triumphed over the Inca…and Sebastian Ben Alcazar, the conqueror of Quito, not sated by such victories, all hankered for more gold and glory through the capture of the king and his possessions. In 1540, inflamed by this vision, Gonzalo Pizarro, brother of the conqueror of Peru, decided to launch an expedition with Francisco de Orellana to conquer the lands of El Dorado and the cinnamon forests. With four thousand Indians, two hundred horse, three thousand swine, and packs of hunting dogs trained to attack Indians, the expedition made its way laboriously through the tropical forests on the east side of the Andes. Hapless forest tribes encountering this army faced an inquisition. When they denied knowledge of the kingdom of El Dorado, they were promptly tortured as liars, burned on barbacoa, or thrown to the ravenous hounds.
“As the expedition descended the Coca watershed towards the Napo river, their provisions — and their Andean Indian bearers — gave out…Disheartened and starving, Pizarro ordered the construction of a raft, sending his second-in-command Orellana ahead to find food. Orellana and his fifty companions never returned. Instead they became the first white men to descend from the headwaters to the mouth of the Amazon. Incensed by the treachery of Orellana and frustrated in his attempts to seek out the kingdom of El Dorado, a furious Pizarro made his return to Quito.” (The Fate of the Forest, Cockburn, pp. 6-7)
As for recent deforestation, there are currently three main factors: “(1) agricultural and livestock expansion (human population growth leads to expanded needs for crop and grazing lands); (2) increased demand for commercial forest products (national economic development and international trade stimulate mainly timber harvesting); and (3) increased demand for noncommercial forest products (fuel wood, fodder, and others). (de Miranda, pp. 156-157)
According to Al Gore in “Earth in the Balance,” “Wherever rain forests are found, they are under siege. They are being burned to clear land for pasture; they are being clear-cut with chain saws for lumber; they are being flooded by hydroelectric dams to generate power.” (Gore, PP. 117-118)
RATES OF DEFORESTATION: FOOTBALL FIELDS OR NOT EVEN ENOUGH FOR A FIRST DOWN?
“With the simple ax, the mighty chainsaw, and all- powerful fire, humankind has chipped away at the earth’s rich mantle over the centuries. Since settled agriculture began about 10,000 years ago, forests and woodlands have dwindled by nearly five billion acres — a third of the original total. For many centuries, this shrinkage of forest cover hindered human progress little, if at all. Indeed, the clearing of trees to make way for cropland and pasture, and the harvesting of wood for fuel and timber, were vital to economic and social development. But in recent decades, the scale and pace of deforestation have greatly accelerated. Each year 28 million acres of tropical forest are destroyed through the combined action of land clearing for crop production, fuelwood gathering, and cattle ranching. Commercial timber harvesting degrades at least an additional 11 million. All told, an area of trees slightly large than New York and Vermont is lost or logged over each year.” (Sandra Postel, Worldwatch Institute)
So is rainforest loss, as Postel suggest, nearly 40 million acres per year – the alleged equivalent of one football field per second? Well that’s the number U.S. News and World Report used as its figure in a major article debunking environmental myths. But other environmentalists use slightly lower figures.
In its publication, “Keeping Tropical Forests Alive,” the World Resources Institute says, “Every year, at least 27 million acres of tropical forests are lost — an area the size of Pennsylvania, Ohio or Virginia. That’s almost 74,000 acres a day — 3,000 acres an hour.” (Which by the way also equals 50 acres per minute, or just under one per second). This number apparently good for Richard Nalley who wrote in Science Digest “man is currently slashing and burning away our rain forests, each year gouging a chunk larger than Virginia from an area roughly the size of the continental U.S. At this rate, all but the most remote lowland rain forest will be stripped bare within 30 years.”
And this number also seems to be good for the National Wildlife Federation, which in a pamphlet co-produced with the World Wildlife Fund called “Tropical Forests: A Resource for the Future” said “Tropical deforestation is occurring at the rate of more than 50 acres per minute. An area the size of New York state is destroyed each year. This rate is high enough to ensure that many countries will be entirely stripped of primary forest within the next decade.”
Or is this number good for NWF? In its Educator’s Guide, a sidebar column said 51 million acres of tropical forest is lost each year (equal to 140,000 acres per day, 5,800 per hour, 96 per minute, and 1.6 per second).
And how about Al Gore? Well in his book, he says “[rain forests] are disappearing from the face of the earth at the rate of one and a half acres a second, night and day, every day, all year round.” This works out to be about the same number NWF uses in its Educator’s Guide.
But lest we forget one of the largest Green groups on the issue, the Rainforest Action Network, they say all these numbers are too low and claim almost two and a half acres per second are wiped out (two U.S. football fields) with 150 acres per minute, 9,000 per hour, about 214,000 per day (an area larger than all of New York City), and 78 million acres per year (an area larger than Poland).
Why these claims are wrong
While some advocates like to make grand, sweeping statements about rainforest loss and put in big numbers that make it sound catastrophic, Roger Sedjo and Marion Clawson, writing for Resources for the Future, dug into the available evidence and said, “Information about the tropical moist forests is relatively scant. What information we do have comes from anecdotal evidence — provided by isolated investigations at single times and places — than from systematic studies conducted over large areas and lengths of time… A hard look at the available data supports the view that some regions are experiencing rapid deforestation. However, the view that this is a pervasive phenomenon on a global level is questionable.” (Rational Readings, Julian Simon, p. 745)
So what does available evidence show? And where do environmentalists begin to get their numbers? Well U.S. News and World Report (12/13/93) explains that while the figure of 40 million acres per year “has taken on a life of its own,” it is being “cited and recited without reference to its origins. Yet almost half the estimated total comes from a very rough estimate made by a Brazilian scientist who used sensors on a U.S. weather satellite to count the number of fires burning in the Amazon at one time in 1988 [at the height of government-subsidized deforestation]. He estimated the size of each, [guessing at the number of acres being cleared by each fire then assumed that 40 percent would never return to their forested condition, and finally doubled this number to arrive at an estimated guess for global deforestation.] The resulting number was into the widely cited report by the World Resources Institute…that helped fuel the alarm over vanishing tropical forests; [and] was cited by Gore and other administration officials last spring in announcing support for the Biodiversity Treaty.
“Last summer, two American researchers [David Skole of University of New Hampshire and Compton Tucker of NASA] took a more careful look. Armed with 210 overhead photographs of the Amazon region taken by Landsat satellites, they compared images from 1978 and 1988, painstakingly entered into a computer every tiny forest clearing, road, and power-line right of way. They found the average rate of rainforest loss was 3.7 million acres per year, or about one-fifth the widely accepted number.”
According to the book, “Eco-Sanity,” “If deforestation in Brazil accounted for half of all rainforest deforestation in the world, as is generally assumed, then the new estimate means the global rate of rainforest deforestation was just 3 million hectares per year (app. 7.5 million acres) during much of the 1980’s. As a percentage of existing rainforests, the annual loss was less than a tenth of one percent.”(Eco-Sanity, p.84)
Another important fact, according to Sedjo and Clawson, relates to a study done by the Food and Agriculture Organization and U.N. Environmental Programme by J.P. Lanly. Lanly is Forest Coordinator for the UNEP/FAO Tropical Resources Assessment Project and his study “indicates that [of the roughly 7 million acres worldwide per year] the undisturbed or “virgin” broadleaved closed forests have a far lower rate of deforestation than the total, being only 0.27 percent annually as compared with 2.06 percent annually for logged over secondary forest.
This figure indicates that deforestation pressure on the more pristine and generally more genetically diverse tropical forests is quite low.” Further, “these findings are in sharp contrast to the conventional view that the tropical forests are `disappearing at an alarming rate’ and suggest that concerns over the imminent loss of some of the most important residences of the world’s diverse genetic base, based on rates of tropical deforestation, are probably grossly exaggerated.” (Simon, Rational Readings, p.746)
Sedjo and Clawson also said “While the local effects of rapid deforestation may be severe, the evidence does not support the view that either the world or the tropics are experiencing rapid aggregate deforestation. Furthermore, the evidence shows that current rates of deforestation are quite modest in much of the world’s virgin tropical forests, for example those of the Amazon; and therefore they are probably in little danger of wholesale destruction in the foreseeable future.” (Eco-Sanity, p.90)
Sandra Brown, professor of forestry at U. of Illinois and Ariel Lugo, project leader at the U.S. Forest Service’s Institute of Tropical Forestry in Puerto Rico also studied available data and “concluded the `dangerous’ misinterpretation and exaggeration of the rate of deforestation has become common.”
As for the amount of deforestation in relation to total forest area, Thomas Lovejoy, then of the World Wildlife Fund, offered a low projection of 50% deforestation between 1980 and 2000 in Latin America and a high of 67%. The source for this was a set of satellite photos taken in 1978 and reported in the Washington Post to show that “as much as one-tenth of the Brazilian Amazon has been razed.” But according to Fulbright scholar and ecologist Robert Buschbacher working in Brazil, the Landsat photos “concluded that 1.55 percent of the Brazilian portion of the Amazon has been deforested.” “On the basis of this and other evidence, Buschbacher says, `Because of a relatively low percentage of forest clearing and the remarkable capacity of the forest to recover its structure…the threat of turning the Amazon into a wasteland is exaggerated.’
“Two U.N. studies and even [ecologist Norman] Myers agree closely in their estimates of the Brazilian deforestation rate — between 0.0025 and 0.004 percent per year…[so] even Lovejoy’s “low” assumption would be perhaps 10 times too high.”
M.K. Muthoo, leader of a FAO/UNDP Project Team, wrote in 1978, “Brazil has abundant natural forest. It holds that world’s biggest tropical forest reserve, in the Amazon, which can be continuously used and improved at the same time, but has hardly been tapped.” (Rational Readings, Simon, pp.745-746).
According to Sedjo, 76 percent of the tropical forest zone is still covered with forest. (True State of Planet, p. 199)
And even the “usually panic-stricken Worldwatch Institute reported in 1992 that `with nearly 90 percent of its groves still standing, by national or international standards, the Brazilian Amazon is relatively untouched.” (Eco-Sanity, p.89)
Two other factors affecting deforestation are also worth noting. First, is that not all deforestation is the same, or has the same characteristics. For example, while much attention is paid to so-called “rainforest” destruction in the Amazon, according to wildlife ecologist Thomas Lacher of Texas A&M, fires reported for Legal Amazonia are very often in the savannah areas where ranching and other activities are being conducted, but it is made to sound like it is in the middle of lush, green jungle.
“Amazonia consists of several types of forest and a large expanse — more than a third of the region — of savannah (cerrado) and semidesert (chaco). `The cerrado and chaco are being destroyed at a much faster rate than anything else,’ Lacher says. `The rate at which they’re being gobbled up by soybean plantations is staggering. Then comes the dry forest, and last is the moist forest. So the actual wettest forest, which is what most of the attention is focused on, is not being hit as much as people sometimes think.” (Science, p. 737)
Lacher also discusses the second factor which is that deforestation rates are not fixed. He notes that most of the deforestation in the Amazon has taken place “along peripheral areas” of the basin and has not been in the heart of the rainforest. He contends there are not roads and other ways to get into the deeper interior — “no way to get in, so it’s not going to happen.” [Dr. Nigel Smith says the national integration highways “remain but a hairline fracture across a sea of forest” and says there is a trend towards use of second growth, or improving existing pasture, rather than clearing mature forest — noting that second growth communities are often closer to the roads and old enough to generate sufficient ash for fertilizing crops].
Lacher calls the conjecture about the rainforest on the verge of disappearing “unwarranted speculation.” He further talks about how “ill-conceived deceived development schemes” attracted poor people to try and settle in the rainforest, that they were “encouraged to move in,” but that they were not adequately backed up with technology transfer, etc. (Phone interview, 11/96)
One of the most infamous of these “schemes” was the vast Polonoroeste settlement program in Rondonia, funded by the international capital of the World Bank (with Thomas Lovejoy one of the advisors). “Before 1989, tax credits, subsidies, and inexpensive loans were given to people who carved farms out of the Amazon rainforest. Laws required owners to clear their properties to receive title to the land, encouraging property owners to clear much greater areas than they expected to farm…[but] many of these policies have been repealed or reformed since 1979…the rate of deforestation in Brazil thus has fallen dramatically.” (Eco-Sanity, p.89)
Backing this idea up is Robert Schneider of the World Bank, who said deforestation rates increased as a demographic transition spread into the rain forest, but “since 1989, the demographic transition has decreased dramatically and so has the rate of deforestation.” (The Dartmouth Review, “Bungle in the Jungle,” Eric Hagen)
Dr. Nigel Smith concludes this area by noting, “In spite of popular belief that the Amazon forest is being totally destroyed, the scale of the region and the concentrated nature of many of the development thrusts have prevented any major ecological catastrophe thus far.” (Smith, “Global Land Use Change,” p.240)
KILLING OFF THE SPECIES OF THE EARTH?
“As many as half of all the living species on earth — some experts actually claim more than 90 percent of all living species — find their homes in tropical rain forests and cannot survive anywhere else. For that reason, most biologists believe that the rapid destruction of the tropical rain forests, and the irretrievable loss of the living species dying along with them, represent the single most serious damage to nature now occurring… the wholesale annihilation of so many living species in such a breathless moment of geological time represents a deadly wound to the integrity of the earth’s painstakingly intricate web of life, a wound so nearly permanent that scientists estimate that recuperation would take 100 million years.” – Al Gore, Earth in the Balance, p.116
“Unknown plants and insects may touch our hearts less than the whales or jaguars, but in the long run they might have been more useful to people and central to the functions of their ecosystems in ways that we cannot imagine. At the present rate, many of them are dead for the rest of history, extinguished by fire, mercury, dioxin, and the loss of the agents of their survival, whether a pollinator, a dispersal agent, a particular type of soil, or a particular tree.” – Alexander Cockburn, Fate of the Forest, p. 58
One cannot enter a discussion about rainforest loss without talking about its effect on the earth’s species. Indeed, with the rainforests thought to be home to at least an estimated half of all species, this is the number one reason advanced as to why we must stop rainforest conversion, and put through an international Biodiversity Treaty that could lock up most of the remaining areas.
Again, just as with talk about rainforest loss, the numbers concerning species loss are equally alarming, and depending on where you look, equally diverse. But generally, the numbers can be traced to two sources: “Dr. Norman Myers, a British ecologist who in 1979 predicted the loss of one million species by the year 2000 [in his famous book, “The Sinking Ark” where he warned the world could “lose one-quarter of all species by the year 2000″]; and Dr. Edward O. Wilson, a Harvard biologist who variously claims that 4,000, 30,000, or 50,000 species are lost each year.” (Eco-Sanity, p.86).
So where do these estimates come from?
Well the answer is definitely not from direct observations. As accurately expressed by biologist Garret Hardin in a quote from Julian Simon, “it is unknowable how many species are being extinguished.” (Scarcity, p.132)
Norman Myers himself says “Unfortunately, we live in a world without sufficient scientists, funding, and above all, time to undertake a conclusive check.” And in 1989 he wrote, “Regrettably, we have no way of knowing the actual current rate of extinction in tropical forests, nor can we even make an accurate guess.” (Scarcity, pp. 77 and 40)
So as is the case with many of the current alleged global environmental “crises,” the predictions about species loss are not based on any real-world observations but rather, guesses and speculations that depend on questionable mathematical models.
Myers himself “offered no basis for his prediction other than to call it a `reasonable working figure’… [And] Wilson cites as the basis of his prediction a mathematical equation known as the species-area curve that relates the size of an island to the number of species found on it. An island 10 square miles in area, for example, is typically found to have half as many species as a similar island of 100 square miles. Wilson argues that tropical forests obey exactly the same rule as their size is reduced. By plugging into the formula the rate at which tropical forests are being cut down throughout the world — Wilson puts it at 2 percent per year — he obtains the figure of 50,000 species lost each year. (U.S. News, p.82)
Under this theory of island biogeography, “The rule that is followed for teaching purposes,” Wilson says, “is that for every 90% loss in area, the number of species that can live indefinitely there is cut by one-half.” (Science, p. 737)
Dr. Michael Coffman explains that island biogeography was first postulated in 1967 and “…is a set of theories of how population and genetic dynamics are affected when stressed on isolated islands in the South Pacific….It postulates that, like isolated islands separated by oceans, forested ecosystems that are separated or “fragmented” by “oceans” of cut-over land, housing tracts, parking lots, and roads are therefore isolated from each other.” To prevent this, corridors and reserves must be created to allow genetic material for the varied species to flow in and out of the natural habitats stabilizing the species populations.” (Coffman, “Biological Diversity,” p.2-3)
But there are several critical elements that cast a long shadow on this scenario. First is the obvious question of just how much rainforest is actually being lost. Wilson and others put in the high estimates, and get high numbers of species loss, but as seen in the previous section, the numbers they use are at least 4 to 5 times higher than, say, the estimates by Lanly.
But even with high estimates of rainforest loss, there are still problems with the “island biogeography” theory. To begin with, it requires two highly questionable assumptions. First is that islands and habitats are analogous. But they are quite different. Islands are surrounded by water which is hostile to most land species. Terrestrial habitat surrounded by land, which can be much more accommodating to migrating species.
“In an address before the National Forum on Biodiversity in 1986, Dr. Ariel Lugo pointed out that according to the only available study of the rate of increase in tropical secondary forests, almost half of the 11.3 million hectares of virgin tropical forest cut annually were turned not into wasteland — the equivalent of water in biogeographical calculations — but secondary forest.” Thus many species were able to survive quite well. (Science, p.737)
In fact, Brian Groombridge who edited the most recent edition of the IUCN’s Red List of Threatened Animals points out that “around 75 percent of recorded extinctions…have occurred on islands; almost all bird and mollusc extinctions have been on islands…very few extinctions have been re