Thursday, November 25, 2004


Spiny oasis of the desert

In the dry Sonoran, animal life revolves around the succulent saguaro cactus       

By Tim Folger 













Courtesy of the Arizona-Sonora Desert Museum


The many-branched saguaro cactus,

which can reach a height of 50

feet, is a nurse to many species of

animal in the Sonoran Desert.

Butterflies, such as Vanessa cardui

(top) suck minerals from the desert mud.

The heat-loving spiny desert iguana

(bottom left) secretes fluorescent

scent markers from pores on its legs.

A solitary hunter, the mountain lion

(bottom right) pads through all four

deserts of the American West.


Arizona-Sonora Desert Museum

2021 N. Kinney Road, Tucson, Arizona

A clay pot containing what seems to be nothing but pebbles rests on a counter near the open-air entrance to the Arizona-Sonora Desert Museum. The nondescript pot is worth a close look, for within it are lessons about the tenacity of life and the emergence of beauty in unexpected places.  Scattered among the reddish-brown pebbles are several tiny green nubs, none more than a fraction of an inch high. These, a museum volunteer says, are five-year-old saguaro cacti. When mature—a long, dry century from now—they could stand up to 50 feet tall, and each will hold as much as eight tons of water, liquid life sequestered over decades in a region that sometimes sees only two inches of rainfall annually.

A forest of saguaros stands sentinel around the mountain-ringed museum, which is located just west of downtown Tucson and east of the Tohono O’odham Indian Reservation. A couple of aviaries and some animal enclosures lie within walls, but most of the museum—the best part—is framed by nothing more than rock and sky. Two miles of trails loop through the 21-acre site, providing a glimpse of the mountain lions, bighorn sheep, beavers, bats, and owls that scrabble a living in the vast Sonoran Desert, which covers some 100,000 square miles in the United States and Mexico. Bristly javelinas, a species of peccary that shares a distant ancestor with pigs, root about in ravines alongside the trails, and the occasional five-inch-long hairy tarantula skitters across the path.

These animals and plants may seem to lead separate lives, but their existence is intricately intertwined. Saguaros, for example, need more than water to survive. They do not self-pollinate, so they must rely on birds, bats, and insects to ferry pollen to and from other cacti in order to reproduce. (A sign along the trail notes that 75 percent of all agricultural crops require insect or bird pollination, a reminder that we are no less dependent on them than is the saguaro.) The animals in turn can’t live without the giant cacti, perhaps the desert’s most reliable source of food and shelter. The pollinators feed on the nectar of the cacti, and later, on the three-inch-long green saguaro fruits that ripen just before the autumn rains. Doves, woodpeckers, and flickers—foot-long birds with bright yellow underwings—bore small nests in saguaro trunks.

Other desert pollinators flit along the trail: assorted butterflies, hummingbirds, and bees. Some of the butterflies feed not only on nectar but on the desert itself. After a rainfall, male butterflies—who taste with their feet—slurp up minerals in mud, obtaining nutrients that they pass to females in a sperm packet that can equal about 10 percent of the male’s body weight. A netted enclosure houses dozens of hummingbirds, each of which draws nectar from about 1,000 flowers to supply the 10 or so calories that they burn each day. A human being with a hummingbird’s metabolism would need about 300 pounds of food and 150 gallons of water daily.

The Desert Museum abounds with glories all year round but is particularly inviting in May or June, when the saguaros flower. A single saguaro may produce as many as 200 creamy three-inch-wide flowers, but only a few bloom after sunset on any night—and only for one night. Even if they are not pollinated, the flowers will close forever the next day. Thanks to their reservoirs of water, though, each cactus can produce flowers—even during droughts—every year of its life, which can last up to two centuries. Compared with this rich and near-rock-like persistence, the nearby city of Tucson, with its swimming pools and water-greedy golf courses, seems to be an unsustainable fantasyland. One can’t help but wonder how much longer it will all last.


Courtesy of Stanford University

Finding Sellaio:

Conserving and Attributing a Renaissance Painting 

Cantor Arts Center, Stanford University

Through November 28, 2004

With the aid of computed tomography, or CT, scan conservators at Stanford University’s Cantor Arts Center have given the Virgin Mary a face-lift. Commandeering the services of the university’s medical center, they zapped The Virgin, Child, and St. John, a Renaissance painting dating to about 1480, with rotating X-ray beams in a CT scanner. By digitally manipulating the three-dimensional images that emerged, the conservators could observe how deathwatch beetle larvae had tunneled through the painting’s four poplar boards, even as they avoided a cheese-based glue that bound the boards together. The scan formed part of a three-pronged prerestoration radiological analysis that included bombardment with ultraviolet rays (above right). Because pigments and varnishes fluoresce differently under UV light, the technique exposed previous retouching attempts. Finally, infrared imaging helped settle a dispute over the identity of the painting’s creator by revealing hatch marks beneath the surface paint—a characteristic of the Florentine artist and Botticelli classmate Jacopo del Sellaio.

Chloe Veltman

Marian Koshland Science Museum

Corner of Sixth and E Streets, NW

Washington, D.C.  (202) 334-1201

Courtesy of Marian Koshland Science Museum

They glisten like gigantic pearls, but these globes evoke the opposite of opulence: Each of the 126 red dots sprinkled across their surfaces represents a region that is or soon will be feeling the effects of climate change. For example, much of low-lying eastern Maryland is vulnerable to flooding, Bangladesh “is projected to lose 17.5 percent of its land if sea level rises about 40 inches,” and East Africa may experience an upsurge in malaria cases if warmer, wetter weather prevails. The row of five globes, each two feet in diameter, forms part of Global Warming Facts and Our Future, one of three new exhibits at the recently opened Marian Koshland Science Museum of the National Academy of Sciences in Washington, D.C.

Created with a $25 million endowment from biologist Daniel Koshland, the sleek, compact museum aims to bring to life the many reports that the National Academy of Sciences presents to Congress. Each of the three exhibits—the others are Wonders of Science and Putting DNA to Work—is light-years beyond the old moldy-dodo-in-a-diorama tradition. Much of the material in Global Warming, for example, is projected on sliding plasma screens. The focus on interactive video allows a faithful simulacrum of the museum to exist online and facilitates shipping exhibits around the country. “We figure exhibits will stay here just two or three years, then go on the road,” says exhibits director Peter Schultz. Suddenly, traveling to D.C. to tour the museums seems so 20th century. Soon, one way or another, the Marian Koshland Science Museum will come to you.

Brad Lemley

The Ancestor's Tale: A Pilgrimage to the Dawn of Evolution
The Ancestor’s Tale: A Pilgrimage to the Dawn of Evolution

By Richard Dawkins, Houghton Mifflin, $28

During the past few decades, zoologist Richard Dawkins has earned his share of admiration and condemnation. At his best, he is Darwin’s most brilliant modern defender and extender, revitalizing evolutionary biology with such piquant coinages as “selfish genes” and “memes,” their cultural equivalent. At his worst, he is a haughty ideologue who launched his 1986 best seller, The Blind Watchmaker, with the absurd declaration that our existence is “a mystery no longer” because the theory of evolution had solved it. In fact, neither Darwin nor his heirs have solved the enormous puzzle of how life began on Earth.

Fortunately, Dawkins has curbed his zealotry and backtracked a tad in The Ancestor’s Tale. The most modest and winning of his eight books, it depicts evolution not as a sterile endgame but as a marvelous adventure, enigmatic in origin, that teems with riddles large and small. Borrowing the narrative structure of Chaucer’s Canterbury Tales, Dawkins guides us on a pilgrimage backward through life’s history. On the way, we pause at critical junctures to rendezvous with common ancestors, such as the tiny shrewlike creatures that outlived the dinosaurs and spawned our primate forebears.

The bulk of his book consists of tales about living species that join us at each meeting point, including the aye-aye,  a grub-digging lemur from Madagascar; the axolotl, a Mexican salamander that retains juvenile gills throughout life; the mudskipper, a crawling, jumping, tree-climbing fish; and the oddball catfish  Synodontis nigriventris. The last swims upside down, grazing on the surface rather than the bottom of ponds; its name, the second half of which means “dark belly,” refers to the fact that its camouflage pattern is the opposite of that seen in most fish. In this case and others, Dawkins conjectures, speciation began with a behavioral innovation that spread, fadlike, and only later became genetically fixed. Other exotic creatures inspire reflections on more general topics: the impact of female sexual choice on male bodies and behavior, the contribution of plate tectonics to biological diversity, and the viability of notions such as race.

In telling these tales, Dawkins demonstrates the extraordinary power of evolutionary theory to answer the myriad questions posed by life. In a recurrent theme, he explains that molecular rather than anatomic comparisons are filling in gaps in the fossil record and revealing surprising linkages between species; they show, for example, that we humans share more genes with bacteria called archaea than they do with other bacterial species. But Dawkins also dwells, refreshingly, on those conundrums that have resisted scientists’ best efforts at understanding. Quoting his old friend John Maynard Smith, the late evolutionary biologist, Dawkins ponders the “scandal” of theorists’ inability to account for the emergence of sex—which, because each individual passes along only half of his or her genes, seems less efficient than asexual cloning or budding. Theories abound, but none entirely persuades. The same is true of the emergence of multicellular life and of nucleated cells.

The deepest enigma of all is, of course, the creation event that got everything rolling some 4 billion years ago. Dawkins reviews the major hypotheses, including the late Francis Crick’s not entirely facetious proposal that extraterrestrials planted the seeds of life on Earth. Then, in an about-turn, he concedes that we may never gather enough evidence to know for certain how life began. It surely must have pained this archrationalist and foe of religious fundamentalism to grant any limitation to evolution. But perhaps Dawkins has finally recognized that mysteries such as the origin of life, far from being an embarrassment to science, serve as its wellspring.         

John Horgan


1. Crimes Against Nature: How George W. Bush and His Corporate Pals Are Plundering the Country and Hijacking Our Democracy

By Robert F. Kennedy, Jr., HarperCollins

2. All Fishermen Are Liars: True Tales From the Dry Dock Bar                                   

By Linda Greenlaw, Hyperion

3. The Last Run: A True Story of Rescue and Redemption on the Alaska Seas                  

By Todd Lewan, HarperCollins

4. The Secret Life of Lobsters: How Fishermen and Scientists Are Unraveling the Mysteries of Our Favorite Crustacean

By Trevor Corson, HarperCollins

5. The Fabric of the Cosmos: Space, Time, and the Texture of Reality

By Brian Greene, Alfred A. Knopf

6. Bush Versus the Environment

By Robert S. Devine, Anchor

7. Compass: A Story of Exploration and Innovation

By Alan Gurney, W. W. Norton

8. A Brief Tour of Human Consciousness: From Impostor Poodles to Purple Numbers

By V. S. Ramachandran, Pi Press

9. Boiling Point: How Politicians, Big Oil and Coal, Journalists, and Activists Have Fueled the Climate Crisis—and What We Can Do to Avert Disaster                                       

By Ross Gelbspan, Basic Books

10. Powerful Medicines: The Benefits, Risks, and Costs of Prescription Drugs

By Jerry Avorn, Alfred A. Knopf




Z-Medica Company

More than 30 American soldiers posted in Afghanistan and Iraq owe their survival to a blood-clotting powder developed in the wake of a shaving accident. Frank Hursey, an engineer working on a NASA project at United Technologies, was studying the adsorptive qualities of volcanic rocks when he nicked his face badly with a razor in his lab. On an impulse, he dabbed some volcanic dust onto his wound and discovered that he could rapidly stanch the bleeding. Hursey later refined his discovery into a powder named QuikClot, made of artificial zeolite granules that can wick away fluid while concentrating the blood’s clotting factors. Rushed into service by the Office of Naval Research during the war in Afghanistan, QuikClot is saving soldiers’ lives on the battlefield, where uncontrolled bleeding is the leading cause of death. QuikClot stops bleeding at the microscopic level: electrostatic charges in the granules grab small water molecules, allowing larger platelet and clotting factors to concentrate at the wound. Because the granules must then be carefully removed, researchers have developed a prototype powder-encasing mesh bag that soldiers could apply to curb hemorrhaging and thus avoid later extraction. QuikClot is also available for first-aid use by hikers and other noncombatants.      

Dan Dubno


Monturiol's Dream: The Extraordinary Story of the Submarine Inventor Who Wanted to Save the World
Monturiol’s Dream: The Extraordinary Story of the Submarine Inventor Who Wanted to Save the World

By Matthew Stewart, Pantheon, $25

In 1867 socialist revolutionary Narcís Monturiol created “the first true submarine,” not as a weapon of war but to protect coral harvesters from drowning. Philosopher Matthew Stewart profiles the eccentric Catalan inventor, whose 56-foot steam-powered Ictíneo II, or “fish boat,” notched many firsts, reaching a speed of 4.5 knots and regularly diving dozens of feet below sea level. 

Maia Weinstock


Defining the Wind: The Beaufort Scale, and How a 19th-Century Admiral Turned Science into Poetry
Defining the Wind: The Beaufort Scale, and How a 19th-Century Admiral Turned Science into Poetry

By Scott Huler, Crown, $23

How tall is the wind? How old? What complexion? Nonsensical questions, of course. Personify the wind as much as you like, but its only meaningful dimension is speed: How hard is it blowing? These days you can answer the question with a pocket anemometer. But there’s always been a need to gauge wind speed with the naked eye—by observing the way it works on the world around you. The classic scale of wind speeds—defined by observable events—is the Beaufort scale, named after Sir Francis Beaufort, the eminent 19th-century British hydrographer. That scale is the subject of Scott Huler’s Defining the Wind.

Huler is an enthusiast, and his enthusiasm for the Beaufort scale begins with its poetry. Huler discovered the scale in the dictionary while working as a copy editor, and he was immediately struck by its verbal economy. It was, he writes, “the ultimate expression of concise, clear, and absolutely powerful writing.” Here, for instance, is the Beaufort scale’s description of light air—Beaufort number 1: “direction of wind shown by smoke but not by wind vanes.” Or take number 9, a 47–54 mile-per-hour strong gale: “slight structural damage occurs; chimney pots and slates removed.” There is something both quixotic and ultimately practical in dividing the indivisible winds, everything from calm to hurricane, into 13 categories. The Beaufort scale implies an imperium of mind over nature. But it also records, in brief, the day-to-day experience of ship captains and windmill operators, whose livelihood and survival depended on keen, measured observation of the wind.

Defining the Wind is a deeply enjoyable foray into the British admiralty, the arcana of 19th-century hydrography and engineering, and the history of the wind. Above all, it helps readers visualize the power of a scientific mind asking direct questions about the world. The book’s only significant flaw is that Huler seems to believe that readers need to be coaxed into reading about wind. It does not make Sir Francis Beaufort more approachable to call him a “guy,” as Huler often does. Nor does it make him more comprehensible to call him “the last eighteenth-century man,” which is simply nonsense, or “the world’s greatest polymath.” What Huler has to show us is fascinating, never mind that we sometimes have to peer over his shoulder to see it.

Verlyn Klinkenborg

A Well-Ordered Thing: Dmitri Mendeleev and the Shadow of the Periodic Table
A Well-Ordered Thing: Dmitri Mendeleev and the Shadow of the Periodic Table

By Michael D. Gordin, Basic Books, $30

The periodic table, that elegant arrangement of elements, took shape as a result of a race to meet a publisher’s deadline. Dmitrii Mendeleev, its celebrated Siberian-born creator, had planned a two-volume textbook on the principles of chemistry. By late January 1869, he had managed to cover just eight elements in the first volume, leaving a further 55—seven-eighths of those then known—for the second. To meet his contract, Mendeleev reorganized the elements based on their atomic weights and arranged them in a table. Then he set off to inspect cheese-making cooperatives for the Imperial Free Economic Society.

The great Mendeleev, it seems, was a well-rounded man. He is principally remembered for a table so logical that he could successfully predict the properties of three elements then missing—all of which were discovered within the next 20 years. But Mendeleev was much more than a chemist, as Princeton University historian Michael Gordin shows. He was an adventurer who went up in a hot-air balloon to observe a solar eclipse, and a flamboyant intellectual who railed against the craze for spiritualism. He also introduced the metric system to the Russian Empire, invented a smokeless gunpowder, and wrote art criticism. Gordin’s kaleidoscopic portrait of the “many Mendeleevs” liberates a man long defined only by the creation of the table that brought order to the study of the elements.          

Chris Jozefowicz

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