Extinction

One scientist has called it man's "brush with extinction."Genetic studies have provided new evidence suggesting that early humans, or their immediate ancestors, were nearly wiped out by a calamity that struck in Africa within the past million years.The event -- an epidemic, perhaps, or a natural disaster or series of them -- may have killed off all but a few hundred or a thousand of their numbers.So few were left to repopulate the Earth, researchers say, that the human race today is left with less genetic diversity than even small communities of chimpanzees now living in Africa.

The greatest commencement address ever is now more than three decades old. And it's safe to say it will never be surpassed or even equaled. It belongs to the ages. In 1979, its author summed up the condition of modern man by noting that, quote, more than at any other time in history, humanity is at the crossroads: One path leads to despair and utter hopelessness; the other, to total extinction. Let us pray we have the wisdom to choose correctly. Unquote. Bang. That's all she wrote.

Oryx and Crake, by Margaret Atwood. Doubleday. 376 pages. $26. Margaret Atwood writes, "Every novel begins with a what if, and then sets forth its axioms. The what if of Oryx and Crake is simply, "What if we continue down the road we're already on?" The answer provided by Atwood's startling novel comes inexorably: Nothing good, nothing good at all. Set in the very near future on a post-apocalyptic Earth onto which an unrelenting sun beats and which is overrun with predatory lab animals, the book details the life and ruminations of Jimmy, aka Snowman (as in Abominable, a rarely seen and possibly mythic creature)

As an ardent supporter of former Republican Sen. Charles McC. Mathias Jr., it saddens me to observe what has happened to his Grand Old Party. It has made a grand terrible bargain with the devil. The equation is easy to see. They don't want to raise taxes on people earning over $1 million a year, which they say is critically important for the average American. To achieve this goal, they say, we must accept some things we may not like from a vocal minority of the party: Limiting women's access to contraception; limiting women's ability to make decisions regarding their health; and limiting men and women's right to marry whomever they wish.

To set the record straight, conservation organizations aren't the only ones that believe red knots should be protected under the Endangered Species Act ("Counting crabs," June 20). The U.S. Fish and Wildlife Service agrees, which is why it placed the shorebird on the ESA candidate list in 2006. And we are not alone in supporting a moratorium on the harvest of horseshoe crabs; leading red knot scientists from the U.S., Canada, Argentina, Chile, Uruguay and Brazil also support a timeout on the take of crabs of Delaware Bay origin — particularly after observing a 5,000 bird drop in wintering locations this year.

AT LEAST five times in the Earth's history, near as scientists can tell, half or more of all plant and animal species were wiped out. They don't know why exactly, but suspect celestial events, such as gamma rays that might have destroyed the Earth's protective atmosphere, exposing all living things below to intense radiation from the sun, followed by a smog-induced ice age. Now, it looks like another mass extinction may be on the horizon - one that...

Here is an excerpt of an editorial from the Star Tribune of Minneapolis, which was published Monday.THE BALD eagle's impending exit from the protected species list is surely something to celebrate, not least for the symbolism of the achievement. But let there be no mistaking the rarity of this victory over the forces of extinction, or the enormity of loss to which it makes exception.Contemporary climate change linked to greenhouse gas emissions is already showing dramatic harm to corals and some other coastal plants and birds.

This may sound apocalyptic, but ant expert and autho Edward O. Wilson warns bluntly that "the sixth great extinction spasm of geological time is upon us, grace of mankind."Only during rare instances in the earth's 4.6-billion-year history have species been driven into extinction as rapidly as they are disappearing now, Mr. Wilson observes in his new book, "The Diversity of Life."Extinctions of the past -- such as the great die-off recorded in fossils and rocks from 65 million years ago -- were cataclysmic, probably caused by the impact of a huge meteorite or by massive volcanic eruptions.

Scientists say they have found the place where an asteroid or comet smashed into Earth 250 million years ago and may have triggered the largest extinction in history, setting the stage for the appearance of dinosaurs and eventually humans. The object created the Bedout crater in a rise of the ocean floor about 120 miles northwest of Australia, researchers say. They say their analysis of the glass and minerals found at key sites in Antarctica and Australia and dug out of the crater, at depths of 10,000 feet, show that the object hit at the same time as the planet began the largest-scale extinction in its history.

IF President Clinton signs the Rio accord to protect rare and endangered species, he will place scientific truth in greater danger than endangered species.A fair reading of the available data suggests a rate of extinction not even one-thousandth as great as doomsayers claim. If the rate were any lower, evolution itself would need to be questioned.The World Wildlife Fund, the main promulgator of alarm about biodiversity and the extinction of species, frames the issue in the starkest terms: "Without firing a shot, we may kill one-fifth of all species of life on this planet in the next 10 years."

To set the record straight, conservation organizations aren't the only ones that believe red knots should be protected under the Endangered Species Act ("Counting crabs," June 20). The U.S. Fish and Wildlife Service agrees, which is why it placed the shorebird on the ESA candidate list in 2006. And we are not alone in supporting a moratorium on the harvest of horseshoe crabs; leading red knot scientists from the U.S., Canada, Argentina, Chile, Uruguay and Brazil also support a timeout on the take of crabs of Delaware Bay origin — particularly after observing a 5,000 bird drop in wintering locations this year.

It was one of Daniel Gabriel Fahrenheit's most famous inventions, in 1714. But after nearly 300 years on the market, the still-common mercury thermometer now appears headed for extinction. While many Maryland residents probably still have them in their medicine cabinets, or on their walls, the retail sale of mercury thermometers has been banned in Maryland since 2002 because of mercury's hazards as a powerful neurotoxin. There are similar bans or restrictions in at least 17 other states, with more such legislation pending elsewhere, according to the Interstate Mercury Education and Reduction Clearinghouse.

I won't waste time telling you how to vote in the upcoming elections, but I will provide some history and context on politics and the environment. The choices for environmental voters used to be harder — and that was a good thing. I began writing about the Chesapeake Bay almost 40 years ago, and for the first couple of decades I don't recall that the environment was a partisan issue. A short list of leaders who were instrumental then in working to restore the bay will make my point.

The ancient "whale" skull discovered eroding from the clay at Calvert Cliffs last spring is actually that of an extinct species of dolphin. Scientists and volunteers extracted the 16 million-year-old fossil from the cliffs over the weekend. They revealed what paleontologist Stephen Godfrey of the Calvert Marine Museum tentatively identified Tuesday as a Eurhinodelphinid , an odd-looking marine mammal with a long, slender upper snout and a lower jaw about half that length. "It looks a little like a swordfish," he said.

T here is a holocaust happening. Right now. And it's not confined to one nation or even one region. It is a global crisis. Species are going extinct en masse. Every 20 minutes, we lose an animal species. If this rate continues, by century's end, 50 percent of all living species will be gone. It is a phenomenon known as the sixth extinction. The fifth extinction took place 65 million years ago, when a meteor smashed into the Earth, killing off the dinosaurs and many other species and opening the door for the rise of mammals.

Amphibians are going extinct around the globe. As a scientist specializing in frogs, I have watched dozens of species of these creatures die out. The extinction of frogs and salamanders might seem unimportant, but this couldn't be further from the truth. These animals regulate their local ecosystems, consume and control populations of mosquitoes and other insects that spread disease, and potentially point the way to new drugs for fighting diseases such as cancer and HIV-AIDS. Their fate is inexorably linked to our own. The biggest danger to most species today is habitat loss.

A team of international scientists says global warming could drive to extinction more than a third of the wildlife in the world's most ecologically sensitive areas by 2050 - and have similar, if less devastating effects on plants and animals worldwide. The researchers' study says rising temperatures will make it impossible for many plants and animals to fight for shrinking habitats in the Amazon, Australia, Africa and Mexico. "It's a wakeup call for conservationists and biologists that climate change is potentially having a dramatic effect on wildlife, especially when you consider the loss of habitat worldwide," said Lee Hannah, a co-author of the study and researcher with Conservation International in Washington.

What ever happened to the White Warty Back? The Lined Pocketbook? The Coosa Elk Toe? That's what Arthur Bogan wants to know. For 18 years, he's been looking for these creatures - all species of freshwater mussel that were once plentiful in Southeastern rivers and streams. Bogan has looked all over, without success, and suspects the species are extinct, victims of pollution, and dams that choke the bivalves with silt. But looking for mussels is tricky work. Bogan sometimes snorkels, or uses a glass-bottomed bucket.

While the last 700 mountain gorillas in the world live under constant threat in central Africa, their guardians are headquartered continents away in Baltimore. The director of a team of "gorilla doctors" who is based at the Maryland Zoo in Baltimore will speak Wednesday in Columbia on working in the wild to rescue the species from the brink of extinction. Dr. Michael Cranfield will give a free presentation on the mission of the Mountain Gorilla Veterinary Project to provide treatment for the powerful primates in their natural habitat in Rwanda, Uganda and the Democratic Republic of the Congo.