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A Curious Look At Species Extinction

June 5th, 2013 No comments

Scientists know that five mass extinctions have occurred since our first prokaryotic ancestors appeared more than three billion years ago.

Now you can make that six.

Nobody knows precisely how many species there are in the world, but fossil evidence and other data suggest that we’re losing species at a rate more than a thousand times faster than at any time during the past sixty-five million years. Many more are at risk. Why? Stresses and strains on natural resources from too many of us. The earth’s human population has more than doubled in the last fifty years and wilt likely exceed eight billion by the year 2025,

According to Harvard biologist Edward O. Wilson, Homo sapiens is “the greatest destroyer of life since the ten-kilometer-wide meteorite that landed near Yucatan and ended the Age of Reptiles sixty-five million years ago,”

As many as 25 percent of the species on earth are likely to be extinct or endangered by the year 2025–and 75 percent by the end of the next century.

“Such losses would destroy humanity’s ability to use these organisms and their genes in any way for human benefit,” says botanist Peter Raven. “The hope that science and engineering will save us is not a hope shared by scientists and engineers,”

The Leonid Meteor Storm

tvbMark your calendar–November 17,1998. About every thirty years, earth passes through the densest part of the debris cloud trailing comet Tempel-Tuttle. This time around, orbiting with us are about five hundred high-priced, sensitive satellites that: we depend on for paging doctors, transacting international business, receiving TV broadcasts, using ATM machines, and pumping gas. These satellites generate $20 billion per year in worldwide business, and this November they’re going to be virtually sandblasted.

Just how intense is the Leonid cloud? Typically, in mid-November; meteors are visible at a rate of about twelve per hour, but in 1966, the last time our orbit took us through this part of the Leonid storm, meteors rained at a rate of 150,000 an hour.

The Leonid cloud is basically just dust and sand, yet these particles have a velocity sufficient to give a speck of sand the energy of a ,22-caliber bullet. As John Pike of the Federation of American Scientists puts it, “Satellites just aren’t designed to have small sticks of dynamite tossed at them.”

Several years ago, a much less intense Perseid meteor storm knocked Europe’s flagship communications satellite, Olympus, permanently out of commission,

The World’s Most Explosive Gas Tank

As many as two hundred billion more barrels of oil re* serves have just been opened to development–a 10 percent increase over the current world total, Even at today’s depressed oil prices, this represents about $4 trillion–by far the largest known undivvied chunk of wealth in the world.

The bad news is that this oil is in one of the most politically chaotic and America-unfriendly regions on earth: the tinderbox of former :Soviet republics Kazakhstan, Turkmenistan, and Azerbaijan. The region is also rife with bloody tribal rivalry, which has led some to the area a Bosnia with oil.

According to Daniel Yergin, energy expert and author of The Prize: The Epic Quest for Oil, Money and Power, “You have thousands of years of accumulated religious and ethnic tensions throughout the region, combined with large geopolitical uncertainties,”

The U.S. is already arm-wrestling with Russia over pipeline routes, and the least problematic route out is through Iran, where Uncle Sam is still known as the Great Satan.

Our Chemical Castration

ccSome studies have shown that male reproductive disorders and infertility are on the rise, sperm counts are down, proportions of abnormal sperm are up, and semen volumes are on the decline. If the trend continues, the researchers say, most men will be effectively sterile by the middle of the next century,

For years, scientists have been investigating the effects of certain man-made chemicals (such as dioxin, DDT, and PCBs) on humans. Some chemicals can mimic natural hormones and disrupt endocrine processes. Laboratory and wildlife studies have shown clear links between so-called environmental hormones and reproductive anomalies in animals,

“I am totally convinced that endocrine disrupters have adverse effects in animals, and therefore I’m very concerned about the potential effects on humans,” says Fred vom Saul, a developmental endocrinologist at the University of Missouri,

The Environmental Protection Agency is concerned enough to have begun considering chemicals’ effects on reproductive health when drafting federal safety guidelines, and the National Academy of Sciences has convened a committee to produce a report on the subject later this fall.

The Next Ice Age

Global warming, it turns out, is just the tip of the iceberg. Higher temperatures could actually wind up precipitating drastic worldwide cooling. As temperatures rise, weather patterns change, meaning more high-latitude rainfall. Rising temperatures also melt ice at the earth’s polar caps. Recent research has revealed evidence of a disintegrating West Antarctic Ice Sheet

All of this dumps more freshwater into the oceans, altering water density and thereby disrupting the massive North Atlantic conveyor-belt current that distributes heat to Europe. This great current, more powerful than a hundred Amazon Rivers, is a key to our temperate climates, and sometimes it shuts down–it has many times, in fact, during the last hundred thousand years. Ice-core and pollen core samples reveal that past disruptions in these currents have caused abrupt and dramatic changes in climate. These sudden changes have occurred fairly frequently–drops of 20 degrees in just a few years.

Even relatively moderate reductions in worldwide temperatures could trigger a chain of events that would lead to ice-age conditions in the Northern Hemisphere–subarctic waters chilling the southern California coast, irish green replaced by Siberian gray, fertile European fields returned to tundra. As Science warned recently, “Reykjavik would be bulldozed into the sea by the iceland Ice Cap.”