by Sally
The years after World War II saw a movement in ecology toward a more quantitatively rigorous science. Ecologists sought to legitimize growing environmental concerns with mathematical equations about population dynamics and species interactions. In 1966, mathematician-biologist Daniel Simberloff and entomologist E.O. Wilson paired up to prove definitively that the number of different species an area of land could support was directly related to its size. They picked a few small mangrove islands off the coast of Florida as their test sites. They first documented the size and number of animal species, all of which were insects, then fumigated the islands, eliminating all animal life. They then monitored the recolonization of the islands by species from nearby islands and the mainland. They found that while species levels always returned to the same size after recolonization, they were not the same in content; that is, the same types of insects did not always repopulate the same islands. These experiments were aimed at providing scientific support for a campaign for larger wildlife preserves. They were meant to show how large, continuous tracts of land were necessary to maintain healthy levels of biodiversity.
Simberloff and Wilson’s experiments were well-intentioned, but their experiments raise some questions about the relationship between science and environmentalism. Science as it is practiced today is highly reductionist, seeking to answer big questions with small experiments. One has to ask whether killing all the bugs on a small mangrove island can really tell us anything helpful about how to not destroy our world. As Donald Worster puts it “how would all the elaborate mathematics help to preserve the earth from degredation?” However, I am inclined to think that despite their penchant for mathematical models, Simberloff and Wilson were not out of touch with the reality of nature. Indeed, they believed that by simulating mass-extinction, they could learn something about the current, real mass extinction that is now happening around us. They simply wanted to test established assumptions about population patterns, something that we certainly need to know more about if we are truly to understand how to protect wild species. A scientist who restricts himself to revering nature and who never tinkers with it is like a surgeon who refuses to dissect a body out of respect for the dead. Yes, they will never do any damage; but neither will they ever learn anything useful.
Watch Simberloff and Wilson talk about their experiment here.
Their segment begins at 34:50.
Saturday, April 30, 2011
Friday, April 29, 2011
Thomas Malthus: A Pessimistic View of Population Control
by Evan G.
The world’s rising human population isn’t the most pressing modern issue. It will nonetheless be a more discussed and debated topic in the near future. But is it really a major cause of concern to us? Thomas Malthus, author most famously of the Essay on the Principle of Population (1798), would probably be less concerned than others, as he thought that population problems were normally resolved on their own. He believed that nature provided necessary checks on the population to rebalance it after it became inflated. When the population was too large, disease and famine were among some of the inevitable outcomes. From his perspective, nature was eliminating a fragment of the population for the whole benefit of society. An example that relates to this concept is after the ‘Black Death’, when the massive population loss led to an overall improvement in life for those who had survived. This was primarily because there was more open land to cultivate and thus more food. Prior to the spreading of the virus, hunger and poverty were widespread throughout Europe. Population growth had begun to outweigh the rate of agricultural production. Based on Malthus’ thinking, the Black Death could therefore be seen as nature’s check on the overcrowded population. Malthus also had an unsympathetic attitude towards poverty, believing that welfare was essentially wasteful because the poor were actually hurting society by draining its resources. There’s certainly some sort of logic to the idea that overpopulation can lead to famine and disease and that welfare is costly, but Malthus’ overall thinking is too cynical and unscientific. There is no known force in nature that governs population control and the poor aren’t unfit to reproduce or undeserving of welfare.
Life expectancy has risen drastically throughout the world over the past hundred years. The earth is more overcrowded with humans now than it has ever been. Hunger still affects millions of people throughout the world, but it is far less prevalent today, especially in advanced industrial nations such as the U.S. Population growth hasn’t outweighed our means to obtain food. One of America’s largest recent issues has been the obesity rate, which is in part due to an endless supply of unhealthy and high-calorie food options. We can feed millions of people today with ease, while for centuries it was a complicated task to provide food for even a relatively small and controllable population. Despite the fact that the world’s population is steadily increasing, we don’t see many of these ‘checks’ from nature that Malthus envisioned. It seems more likely that we as a society are learning how to better handle and manage large populations. These checks from nature such as famine and hunger are actually signs of society’s failure to properly manage its population. Some could take Malthus’ ideas further by interpreting a natural disaster such as an earthquake, tornado, or hurricane as nature’s way of rebalancing the population. But this is more like the ideology of a religious extremist than that of a rational scientist. Nature doesn’t intend to eliminate certain humans for the benefit of other humans. This is the type of thinking that separates man from himself and nature.
The world’s rising human population isn’t the most pressing modern issue. It will nonetheless be a more discussed and debated topic in the near future. But is it really a major cause of concern to us? Thomas Malthus, author most famously of the Essay on the Principle of Population (1798), would probably be less concerned than others, as he thought that population problems were normally resolved on their own. He believed that nature provided necessary checks on the population to rebalance it after it became inflated. When the population was too large, disease and famine were among some of the inevitable outcomes. From his perspective, nature was eliminating a fragment of the population for the whole benefit of society. An example that relates to this concept is after the ‘Black Death’, when the massive population loss led to an overall improvement in life for those who had survived. This was primarily because there was more open land to cultivate and thus more food. Prior to the spreading of the virus, hunger and poverty were widespread throughout Europe. Population growth had begun to outweigh the rate of agricultural production. Based on Malthus’ thinking, the Black Death could therefore be seen as nature’s check on the overcrowded population. Malthus also had an unsympathetic attitude towards poverty, believing that welfare was essentially wasteful because the poor were actually hurting society by draining its resources. There’s certainly some sort of logic to the idea that overpopulation can lead to famine and disease and that welfare is costly, but Malthus’ overall thinking is too cynical and unscientific. There is no known force in nature that governs population control and the poor aren’t unfit to reproduce or undeserving of welfare.
Life expectancy has risen drastically throughout the world over the past hundred years. The earth is more overcrowded with humans now than it has ever been. Hunger still affects millions of people throughout the world, but it is far less prevalent today, especially in advanced industrial nations such as the U.S. Population growth hasn’t outweighed our means to obtain food. One of America’s largest recent issues has been the obesity rate, which is in part due to an endless supply of unhealthy and high-calorie food options. We can feed millions of people today with ease, while for centuries it was a complicated task to provide food for even a relatively small and controllable population. Despite the fact that the world’s population is steadily increasing, we don’t see many of these ‘checks’ from nature that Malthus envisioned. It seems more likely that we as a society are learning how to better handle and manage large populations. These checks from nature such as famine and hunger are actually signs of society’s failure to properly manage its population. Some could take Malthus’ ideas further by interpreting a natural disaster such as an earthquake, tornado, or hurricane as nature’s way of rebalancing the population. But this is more like the ideology of a religious extremist than that of a rational scientist. Nature doesn’t intend to eliminate certain humans for the benefit of other humans. This is the type of thinking that separates man from himself and nature.
Thursday, April 7, 2011
Protecting the Predators
by Mary McCarthy
The 23,208 wolves and coyotes destroyed by American ranchers, farmers, hunters, and Forest Service agents during the single year of 1907 is a staggering representation of the mass slaughter of predatory animals condoned by the Bureau of Biological Survey (Vernon Bailey, “Destruction of Wolves and Coyotes: Results Obtained During 1907,” Bureau of Biological Survey, Circular no. 63, 1908). By the mid 1920s, however, some ecologists began to question the wisdom of completely exterminating animals whose important ecological roles were starting to be recognized. Charles C. Adams was one of the early voices for protecting the predatory animals of the United States. His article, “The Conservation of Predatory Mammals,” outlines possible management strategies and justifies the protection of “predacious animals” due to their “great scientific, educational, recreational and economic value to society” (Charles Adams, “The Conservation of Predatory Mammals,” Journal of Mammalogy, Vol. 6, 1925, 94). Even more revolutionary was Adams’ call for public park and forest lands to be used as sanctuaries for all types of wild animals, not just the game animals that dominated contemporary management concerns: “As, however, public forests are primarily intended for the public good, the public has a right to decide how these areas should be used. Because of their huge acreage…they have without question areas naturally suitable for the preservation of all kinds of predators, large and small, but not of course in unlimited numbers” (Adams, 91). At that time, the Bureau of Biological Survey was still supporting the extermination of “vermin” on National Park land, a concept that seems very far removed from our current ideology of parkland as a refuge for wild animals.
“The Conservation of Predatory Mammals” remains relevant today, especially regarding current efforts to reintroduce predators to areas where the extermination programs were successful. The Mexican grey wolf, once found in small areas of Arizona, New Mexico, and Texas, was completely eliminated from the Southwestern United States, thanks in part to the efforts of the Bureau of Biological Survey. Adams’ evaluation of predators as having important scientific and ecological value is similar to the guiding principles of the Mexican grey wolf reintroduction programs that aim to reestablish wild wolf populations in the Apache-Sitgreaves and Gila National Forests. Though government organizations may have officially abandoned extermination in favor of conservation, and embraced the idea of public lands as refuges rather than killing grounds, the reintroduction of predators remains a highly controversial topic, especially to ranchers and farmers. Adams’ writing serves as a reminder that these predators, despite their many human enemies, should still have a place of sanctuary, “that these animals are worth preservation, somewhere” (Adams, 86). Thus, as the political battle wages over wolf reintroduction, let us remember Adams’ conclusions that the value of a predator comes in many forms; we would be scientifically, socially, and ecologically poor without these valuable animals.
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