RE: Are Humans Gaia's Immune System Against Impacts?

[Thomas Green]

Title: Message

An interesting pairing of articles:  the metaphysical Gaia hypothesis along with an article describing a need to employ scientific principles so one can having understanding vs. a belief.   The half-baked thought of "Perhaps she evolved technologically sophisticated, big-brained mammals who can travel in space as a way of protecting herself from asteroids." is more than a little ironic, since evidence is mounting that the Chicxulub did indeed cause the dinosaur demise that subsequently set the ecological stage for mammals to diversify and lead to humans.   Gaia is certainly a romantic idea, but the concept of a goddess directing evolution is certainly in the realm of mysticism.  Maybe the article should've focused on how evolution may be forming a resilience to massive disruptions... which would also be a weak hypothesis, but at least not require a goddess weaving a web.  250 million years is a long time between impacts, so it's an incredible stretch to think of life being able to evolve traits to survive.    Not to entirely bash the article.  If one takes Gaia as a metaphor for the "super-ecosystem" of earth, then certainly the evolution of intelligence can bestow an awareness on a population; one that can completely evaluate causes and their effects.  To paraphrase Aldo Leopold, for a being to understand and care about other animals is something new under the sun.   The problem with humans is they just don't live long enough to fully appreciate their own impacts...  although with our population literally exploding on the exponential path, we're starting to have massive effects within one generation.  I think it's estimated that there will be 8 billion people on this planet in 30 more years, with no sign of slowing.    If humans are supposed to be earth's immune system, the body is about to be overwhelmed with doing nothing but cranking out white-blood cells at the expense of every other tissue.  A wise rancher tries to calculate a carrying-capacity for his little plot of land, and manage the herd.  What is the earth's carrying capacity for people... and are we really wise enough to manage it?    Habitat destruction is increasing at such a pace already that biologists consider the current rate of extinction as a mass-extinction event (from a fossil record perspective).  With population pressure only increasing, I find it highly optimistic, and more than a little arrogant, to think that humans evolved to be a "hero" organism while our hands are still weilding the murder weapon.  Maybe things will get better, and biodiversity will stabilize... but saving the planet from a big rock that may hit 10,000 years in the future won't be enough if we can't save it from ourselves now.   Regards, Tom Green   -----Original Message----- From: LARRY KLAES [mailto:[EMAIL PROTECTED]] Sent: Wednesday, August 21, 2002 12:55 PM To: europa Subject: Are Humans Gaia's Immune System Against Impacts? DEFENDERS OF EARTH: ARE HUMANS GAIA'S IMMUNE SYSTEM? From Reason Online, 31 July 2002   http://reason.com/rb/rb073102.shtml By Ronald Bailey The Gaia hypothesis, which holds that Earth is a living organism in its own right, typically has been used to highlight man's role in messing up the environment. But if the latest warning of a possible ecological catastrophe turns out to be accurate, people could end up helping Gaia rather than harming her. The Gaia hypothesis--named after the Greek word for the Earth goddess, also translated as "Earth Mother"--was devised in the 1970s by atmospheric chemist James Lovelock and microbiologist Lynn Margulis. In Gaia: A New Look at Life on Earth, Lovelock and Margulis wrote, "The entire range of living matter on Earth from whales to viruses and from oaks to algae could be regarded as constituting a single living entity capable of maintaining the Earth's atmosphere to suit its overall needs and endowed with faculties and powers far beyond those of its constituent parts." They said Gaia could be defined as "a complex entity involving the Earth's biosphere, atmosphere, oceans, and soil; the totality constituting a feedback of cybernetic systems which seeks an optimal physical and chemical environment for life on this planet." Most evolutionary biologists reject the Gaia hypothesis as an unscientific, although poetic, metaphor. But let's not let such quibbles trouble us today. According to the Gaia hypothesis, the history of life on Earth can be regarded as a progressive modification of the planet's chemistry and temperature by biological organisms acting in ways that enhance their own flourishing. For example, Earth's atmosphere was modified over billions of years by photosynthetic microorganisms from one that was predominantly carbon dioxide and methane into its current oxygen-rich state. This oxygen-rich atmosphere apparently set the stage for the evolution of multicellular life that took off in earnest during the "Cambrian explosion" some 540 million years ago. In the millions of years following the Cambrian explosion, Gaia took out all the stops, and the earth saw a vast diversification of life and finally the colonization of land by plants and animals. Then, 250 million years ago, the Permian party came to a catastrophic end in which 95 percent of Earth's species were wiped out. Gaia picked herself up and started over. Dinosaurs and flowering plants eventually evolved to dominate the landscape in the Cretaceous Period (146 to 65 million years ago). At the time, our tiny mammalian ancestors were scrambling about the leaf litter, trying to avoid becoming dinosaur snacks. The cornucopia of Cretaceous life came to an abrupt end 65 million years ago, when 70 percent of all species became extinct. The leading explanation for these mass extinctions is the havoc caused by asteroids slamming into the earth. The asteroid that brought the Cretaceous Period to a close is thought to have been 10 miles wide, creating the 110-mile-diameter Chicxulub crater just off Mexico's Yucatan peninsula. The massive Permian extinction is thought to have been caused by an asteroid 10 times bigger. It's inevitable that Earth will be struck again. In 1908 a small comet or asteroid, about 165 feet in diameter, exploded over the remote Tunguska region of Siberia, releasing energy equivalent to 15 megatons of TNT, 1,000 times stronger than the atomic bomb dropped on Hiroshima. In 1989 an asteroid measuring a quarter of mile in diameter missed Earth by just 400,000 miles. In 1994 the house-sized asteroid XM1 was spotted only 14 hours before passing within 65,000 miles of Earth, well inside the moon's orbit of 238,000 miles. In June an asteroid the size of a soccer field missed Earth by 75,000 miles. Scientists estimate that an asteroid with a diameter of a kilometer (0.62 mile) could destroy civilization by drastically changing the earth's climate after impact and kill one-quarter of the world's population. This disaster scenario was popularized in 1998 by two mediocre movies, Deep Impact and Armageddon. So far astronomers have identified over 26,000 asteroids in our solar system. The 1,700 or so that regularly pass close to Earth's orbit are designated Near Earth Objects, or NEOs. Six hundred NEOs measure more than a kilometer in diameter. The National Aeronautics and Space Administration's Jet Propulsion Laboratory helpfully lists more than a score of upcoming near misses for those who have a morbid interest in such things. The latest scare occurred last week with the detection of asteroid 2002 NT7, which measures more than a mile in diameter. Initial calculations showed that there was a small probability that it might hit the earth on February 1, 2019. Fortunately, subsequent analysis found that civilization will be spared until at least February 1, 2060, when there is a very tiny chance the asteroid will hit us. In the meantime, NASA and the European Space Agency are increasing their monitoring of NEOs and thinking of ways to deflect or blow up any asteroids that threaten to smash into Earth. What do asteroid impacts have to do with the Gaia hypothesis? In Gaia: A New Look at Life on Earth, Lovelock asked, "To what extent is our collective intelligence also a part of Gaia? Do we as a species constitute a Gaian nervous system and a brain which can consciously anticipate environmental changes?" Perhaps Gaia has gotten tired of being whacked by asteroids and having to restart biological evolution over and over again. Perhaps she evolved technologically sophisticated, big-brained mammals who can travel in space as a way of protecting herself from asteroids. Like antibodies that protect the body from invading disease organisms, humans can defend our Earth Mother against extraterrestrial intruders. Just a thought. Ronald Bailey, Reason's science correspondent, is the editor of Global Warming and Other Eco Myths (Prima Publishing) and Earth Report 2000: Revisiting the True State of the Planet(McGraw-Hill). Copyright 2002, Reason Online ============ AND FINALLY: WHY SMART PEOPLE BELIEVE WEIRD THINGS TOO Scientific American, September 2002   http://www.sciam.com/article.cfm?articleID=0002F4E6-8CF7-1D49-90FB809EC5880000&pageNumber=2&catID=2 Smart People Believe Weird Things   Rarely does anyone weigh facts before deciding what to believe By Michael Shermer In April 1999, when I was on a lecture tour for my book Why People Believe Weird Things, the psychologist Robert Sternberg attended my presentation at Yale University. His response to the lecture was both enlightening and troubling. It is certainly entertaining to hear about other people's weird beliefs, Sternberg reflected, because we are confident that we would never be so foolish. But why do smart people fall for such things? Sternberg's challenge led to a second edition of my book, with a new chapter expounding on my answer to his question: Smart people believe weird things because they are skilled at defending beliefs they arrived at for nonsmart reasons. Rarely do any of us sit down before a table of facts, weigh them pro and con, and choose the most logical and rational explanation, regardless of what we previously believed. Most of us, most of the time, come to our beliefs for a variety of reasons having little to do with empirical evidence and logical reasoning. Rather, such variables as genetic predisposition, parental predilection, sibling influence, peer pressure, educational experience and life impressions all shape the personality preferences that, in conjunction with numerous social and cultural influences, lead us to our beliefs. We then sort through the body of data and select those that most confirm what we already believe, and ignore or rationalize away those that do not. This phenomenon, called the confirmation bias, helps to explain the findings published in the National Science Foundation's biennial report (April 2002) on the state of science understanding: 30 percent of adult Americans believe that UFOs are space vehicles from other civilizations; 60 percent believe in ESP; 40 percent think that astrology is scientific; 32 percent believe in lucky numbers; 70 percent accept magnetic therapy as scientific; and 88 percent accept alternative medicine. Education by itself is no paranormal prophylactic. Although belief in ESP decreased from 65 percent among high school graduates to 60 percent among college graduates, and belief in magnetic therapy dropped from 71 percent among high school graduates to 55 percent among college graduates, that still leaves more than half fully endorsing such claims! And for embracing alternative medicine, the percentages actually increase, from 89 percent for high school grads to 92 percent for college grads. We can glean a deeper cause of this problem in another statistic: 70 percent of Americans still do not understand the scientific process, defined in the study as comprehending probability, the experimental method and hypothesis testing. One solution is more and better science education, as indicated by the fact that 53 percent of Americans with a high level of science education (nine or more high school and college science/math courses) understand the scientific process, compared with 38 percent of those with a middle-level science education (six to eight such courses) and 17 percent with a low level (five or fewer courses). The key here is teaching how science works, not just what science has discovered. We recently published an article in Skeptic (Vol. 9, No. 3) revealing the results of a study that found no correlation between science knowledge (facts about the world) and paranormal beliefs. The authors, W. Richard Walker, Steven J. Hoekstra and Rodney J. Vogl, concluded: "Students that scored well on these [science knowledge] tests were no more or less skeptical of pseudoscientific claims than students that scored very poorly. Apparently, the students were not able to apply their scientific knowledge to evaluate these pseudoscientific claims. We suggest that this inability stems in part from the way that science is traditionally presented to students: Students are taught what to think but not how to think." To attenuate these paranormal belief statistics, we need to teach that science is not a database of unconnected factoids but a set of methods designed to describe and interpret phenomena, past or present, aimed at building a testable body of knowledge open to rejection or confirmation. For those lacking a fundamental comprehension of how science works, the siren song of pseudoscience becomes too alluring to resist, no matter how smart you are. -------------------------------------------------------------------------------- Michael Shermer is publisher of Skeptic magazine (www.skeptic.com) and author of In Darwin's Shadow and Why People Believe Weird Things, just reissued. Copyright 2002, Scientific American