Friday, February 26, 2016

Human Cancer

Human Cancer

When a spot on a person's skin changes color, becomes tough or rough and elevated or ulcerated, bleeds, scales, scabs over and fails to heal, it's time to consult a doctor. For these are early signs of skin cancer.
As seen by astronauts and photographed from space by satellites, millions of manmade patterns on the land surface of Earth resemble nothing so much as the skin conditions of cancer patients. The transformation of the natural contours of the land into the geometric patterns of farm fields, the straightening of meandering rivers into canal-like channels, and the logging of forests into checkerboard clearcuts all have their counterparts in the loss of normal skin markings in cancer victims. Green forests logged into brown scrub and overgrazed grasslands bleached into white wasteland are among the changes in Earth's color. Highways, streets, parking lots and other paved surfaces have toughened Earth's surface, while cities have roughened it. Slag heaps and garbage dumps can be compared to raised skin lesions. Open-pit mines, quarries and bomb craters, including the 30 million left by US forces in Indochina, resemble skin ulcerations. Saline seeps in inappropriately irrigated farm fields look like scaly, festering sores. Signs of bleeding include the discharge of human sewage, factory effluents and acid mine drainage into adjacent waterways, and the erosion of topsoil from deforested hillsides to turn rivers, lakes and coastal waters yellow, brown and red. The red ring around much of Madagascar that is visible from space strikes some observers as a symptom that the island is bleeding to death.
If skin cancer were all that ailed Earth, the planet's eventual recovery would be less in doubt. For with the exception of malignant melanoma, skin cancer is usually curable. But the parallels between the way cancer progresses in the human body and humans' progressively malignant impact on Earth are more than skin-deep. Consider:
Cancer cells proliferate rapidly and uncontrollably in the body; humans continue to proliferate rapidly and uncontrollably in the world. Crowded cancer cells harden into tumors; humans crowd into cities. Cancer cells infiltrate and destroy adjacent normal tissues; urban sprawl devours open land. Malignant tumors shed cells that migrate to distant parts of the body and set up secondary tumors; humans have colonized just about every habitable part of the globe. Cancer cells lose their natural appearance and distinctive functions; humans homogenize diverse natural ecosystems into artificial monocultures. Malignant tumors excrete enzymes and other chemicals that adversely affect remote parts of the body; humans' motor vehicles, power plants, factories and farms emit toxins that pollute environments far from the point of origin.
A cancerous tumor continues to grow even as its expropriation of nutrients and disruption of vital functions cause its host to waste away. Similarly, human societies undermine their own long-term viability by depleting and fouling the environment. With civilization as with cancer, initial success begets self-defeating excess.
It's easy to dismiss the link between cancer the disease in humans and humans as a disease on the planet as both preposterous and repulsive--or as a mere metaphor rather than the unifying hypothesis its leading proponent claims for it. Only a handful of limited-circulation periodicals, including this one (see Forencich 1992/93), have granted the concept a respectful hearing.
Accepting the humans-as-cancer concept comes easier if one also accepts the Gaia hypothesis that the planet functions as a single living organism. To be sure, the Earth is mostly inanimate. Its rocky, watery surface supports only a relatively thin layer of plants, animals and other living organisms. But so, too, is a mature tree mostly dead wood and bark, with only its thin cambium layer and its leaves, flowers and seeds actually alive. Yet the tree is a living organism. Earth behaves like a living organism to the extent that the chemical composition of its rocky crust, oceans and atmosphere has both supported and been influenced by the biological processes of living organisms over several billion years. These self-sustaining, self-regulating processes have kept the Earth's surface temperature, its concentrations of salt in the oceans and oxygen in the atmosphere, and other conditions favorable for life.
James Lovelock, who propounded the Gaia hypothesis in 1979, initially rejected humans' cancer-like impacts as a corollary, declaring flatly: "People are not in any way like a tumor" (Lovelock 1988, p. 177). But before long he modified this view, observing: "Humans on the Earth behave in some ways like a pathogenic micro-organism, or like the cells of a tumor or neoplasm" (Lovelock 1991,p. 153).
Others have stated the connection more strongly. "If you picture Earth and its inhabitants as a single self-sustaining organism, along the lines of the popular Gaia concept, then we humans might ourselves be seen as pathogenic," Jerold M. Lowenstein, professor of medicine at the University of California, San Francisco, has written. "We are infecting the planet, growing recklessly as cancer cells do, destroying Gaia's other specialized cells (that is, extinguishing other species), and poisoning our air supply....From a Gaian perspective... the main disease to be eliminated is us" (Lowenstein 1992).
Dr. Lowenstein isn't the first physician to examine the planet as a patient and find it afflicted with humanoid cancer. Alan Gregg pioneered the diagnosis. As a long-time official of the Rockefeller Foundation, responsible for recommending financial grants to improve public health and medical education, Dr. Gregg traveled widely in the years following World War II and observed the worldwide population boom. By 1954 he had seen enough. In a brief paper delivered at a symposium and subsequently published in Science, Gregg (1955) compared the world to a living organism and the explosion in human numbers to a proliferation of cancer cells. He sketched other parallels between cancer in humans and humans' cancer-like impact on the world. And he expressed hope--unrealized to this day--that "this somewhat bizarre comment on the population problem may point to a new concept of human self-restraint."

It has fallen to a physician who is also an epidemiologist to flesh out and fill in Gregg's sketchily drawn analysis. Warren M. Hern wrote his Ph.D. dissertation on how the intrusion of Western civilization has increased birth rates among Peruvian Amazon Indians. He does his bit to keep the US birth rate down by operating an abortion clinic in Boulder, Colorado. Hern (1990) published a major article that laid out in detail, and buttressed with anthropological, ecological and historical evidence, the ways in which the human species constitutes a "malignant eco-tumor." He proposed renaming us Homo esophagus (for "the man who devours the ecosystem"). Illustrations accompanying the article included aerial photographs of US cities juxtaposed with look-alike photos of brain and lung tumors.