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Mapmakers have tried with varying precision to locate themselves in the world for more than 2,000 years. Their achievements, even early on, were impressive. But there were problems, too, like those medieval maps featuring monsters and dragons. Nonetheless, when Ptolemy wrote his Geographia around A.D. 150, he had already figured out most of the basic elements of cartography as we know it. His maps, rediscovered and published throughout Europe just before Columbus set sail, look strangely familiar to modern eyes: a round Earth projected on a flat surface, its landmasses and blue seas crisscrossed by lines of latitude and longitude. Only reluctantly, one senses, did Renaissance mapmakers label the edges of their maps "Terra incognita."

The cartographic calculations of the second-century Greek scholar Claudius Ptolemy profoundly influenced conceptions of geography and mapmaking during the Renaissance. The above map appeared in a 1482 German edition of Ptolemy's classic work Geographia.

Photograph courtesy of the Newberry Library

Both the scientific and imperial urges to fill in those unknown spaces are explored in a new exhibition in Chicago, Cartographic Treasures of the Newberry Library, which runs from October 10 through January 19, 2002. The collection of 300,000 rare maps from which these treasures have been selected includes all but one edition of the Geographia, two of which were published in 1480 and 1482 based on Ptolemy's original calculations. "Maps document how the scientific conception of the world has changed over time," says exhibition cocurator Jim Akerman. In the early 1500s, he points out, cartographers' grasp of the world was as incomplete as our current knowledge of the cosmos.

One of the oldest and most beautiful of the nearly 80 maps on display was hand-illuminated on vellum in 1456. It is almost childlike in its simplicity, with the names of Mediterranean cities printed right side up and upside down around the sea's perimeter. Yet the map is remarkably accurate; its colored rhumb lines, which represent compass bearings, could be used by sailors to navigate out of sight of land by calculating a direct course between ports of call. One hundred years later, a Bavarian mathematics professor named Apian, aided by an odometer and a compass, produced the first national survey map, using triangulations taken from high vantage points. His work succeeded in placing mountains and towns in at least a rough approximation to their actual locations. In 1745 the French government used this same method to create the first detailed national topographic map based on an instrument survey— a landmark advance in cartography.

The Newberry exhibition organizes the evolution of geographic knowledge and mapmaking into several topics. "Grasping the World," for example, traces early attempts to visualize the globe and man's place on it. "Inventing the Nation" demonstrates how the concept of nationhood depends on accurate maps, while "Contesting Places" displays war maps that were used to challenge those same boundaries.

This folding paper globe, invented by a California schoolteacher, dates from 1869.Photograph courtesy of the Newberry Library

It's only in the last hundred years or so that maps have given us the ability to know for certain where we are going and what we will find when we arrive. The Newberry exhibition shows us exactly how far we've traveled to get there.


Evolution Produced by WGBH Educational Foundation and Clear Blue Sky Productions.

Acanthostega lived some 360 million years ago and like most fish subsisted in water and breathed through gills. But the rocks and dense vegetation of its marshy environs posed navigational challenges. So Acanthostega emerged as a striking example of nature's radical inventiveness: Instead of fins, it was equipped with legs and toes to crawl along the marsh's bottom. Over millions of years, the descendants of Acanthostega encountered other challenging environments that gradually reshaped their limbs too: Consider the wings of a falcon or the legs of a kangaroo.

Biologists rely on the theory of evolution through natural selection proposed by Charles Darwin to explain such transformations. Species are thought to arise and change because the individuals best adapted to their environment survive and reproduce. But over the last 140 years, that theory has been subjected to numerous challenges. Skeptics, and even supporters, have questioned how natural selection alone could have hatched solutions as varied as sexual reproduction and the strange anatomy of the duck-billed platypus. In adapting itself to new evidence, evolutionary theory has, like Acanthostega, generated its own ingenious solutions.

The evolution of Darwin's theory is at the heart of an eight-hour PBS miniseries to be broadcast September 24 to 27. The filmmakers have organized the programs around some of the greatest challenges the theory and its proponents have had to overcome, including the ongoing search for crucial bits of scientific evidence and the protests of evangelical Christians.

Each episode is devoted to a specific question: How could incremental changes in individual organisms lead to entirely new species? How did the human mind develop? How have extinctions altered evolution's course? In answering the big questions, the filmmakers show how researchers have hit upon brilliant solutions to many of the little ones. Take, for instance, the evolution of the eye. Biologists have long wondered how natural selection alone could account for the eye's gradual development from the rudimentary light-sensing organs of primitive animals to its current design. After studying a variety of animals, Dan-Eric Nilsson of the University of Lund in Sweden built a plastic model that demonstrates one possible explanation. A simple plastic cavity with a translucent screen in the back acts as a retina. Each new improvement devised by Nilsson at first makes only a marginal difference in the pattern of light and shadows cast on the screen. But when he places a plastic slip over the front of the cavity, gradually filling it with water to make a lens, the indistinct patterns sharpen into a perfect image.

As you'd expect, the PBS series offers a companion book. But unlike other coffee-table tomes accompanying such programs, Carl Zimmer's Evolution (HarperCollins, $40) is particularly worthy of notice. Zimmer follows the basic plan of the series, but the story he tells is much broader, offering answers to questions you'll wish you had thought of. Jeffrey Winters


Monsters in a Box

Assemble your own Tyrannosaurus rex at home

Piecing together entire skeletons from mangled pieces of bone is truly a feat of puzzle-solving skills. But you don't have to be a paleontologist at a museum to participate. Now anyone can experience some of that excitement (and perhaps frustration with Anatomics building kits (Inhabit Toys, Start with an aquatic plesiosaur ($24.95) or a carnivorous velociraptor ($19.95).

The Anatomics velociraptor, assembled below, features the dinosaur's sickle-shaped "killing claw" on its hind foot, which the creature used to tear into smaller, plant-eating prey.

There are about 150 tiny pieces to each model, but unlike the fossils that real, live paleontologists have to deal with, these come with handy instructional diagrams. The bits pop together mostly with ball-and-socket connections. This makes the final model surprisingly sturdy while allowing each joint to move in a pleasingly organic way, thus approximating how the skeleton would bend and flex if cartilage and tendons were in place.

Despite the name, Anatomics are obviously not anatomically correct— the velociraptor, at best, is missing a few of its ribs. But the models are realistic enough to give a sense of the everyday problems faced by paleontologists who return from their field expeditions with a pile of fossils. For instance, the Tyrannosaurus rex ($24.95) can be positioned in the upright, tail-dragging stance that was originally thought to be its correct posture. Or you can bend it into the now widely accepted pose in which it leans over with its tail held off the ground as a counterbalance. The fact that the model works in either of these configurations gives further insight into the difficult decisions that paleontologists must make when assembling their bones and bits.

Anatomics builders have another advantage over museum scientists: When they're finished assembling an actual dinosaur, they can just as easily reassemble the bones to make the Loch Ness monster (which in popularized drawings resembles the plesiosaur) or some swamp creature out of an old sci-fi movie. And there's no fear of professional ridicule. Fenella Saunders


Stars in Their Eyes

Imagining Space: Achievements, Predictions, Possibilities 1950-2050 Roger D. Launius and Howard E. McCurdy Chronicle Books, $35. White Mane Publishing Company, $24.95.

Although the space era burst into public consciousness in 1957 with the launch of Sputnik, it really kicked off seven years earlier with the George Pal movie Destination Moon, which enthralled audiences with its realistic depiction of a lunar expedition. Space exploration became real not when it happened but when a large number of people started to believe it could happen.

In one artist's depiction, a U.S. spacecraft fires on enemy targets in the year 2025.Photograph courtesy of Chronicle Books

That philosophical perspective sets Imagining Space apart from other lavishly illustrated books that chronicle NASA's triumphs or speculate on fantastic adventures yet unseen. Roger Launius, a NASA historian, and Howard McCurdy, a professor of public affairs at American University, contrast the reality of spaceflight with the dreams and aspirations that motivated it. Some of these, such as the belief that giant space habitats could alleviate overcrowding on Earth, now look head-spinningly naive. Others, such as the desire to find alien life, persist in altered form. And still others, such as the quest for military supremacy in space, could have been ripped from today's newspapers.

Regardless of their impulses, space prognosticators suffered from blurry vision. Nearly everyone, from NASA administrators to science-fiction writers, expected the cost of rocketry to plummet. As Launius and McCurdy describe in discouraging detail, the price of reaching orbit remains jammed at $10,000 to $40,000 per pound. On the flip side, nearly everyone underestimated how advances in robotics and communications technology would transform the exploration of space. Robert Goddard, the rocket pioneer, imagined using a giant flashbulb to signal when a rocket had reached the moon. Today anyone with a computer and a modem can see Jupiter though the eyes of the Galileo spacecraft.

Undaunted, Launius and McCurdy try to anticipate the shape of space exploration to come. Some of their predictions may surprise those accustomed to the rosy tone of official NASA pronouncements. A chapter on space warfare details the inevitable growth of military forces in orbit. Looking at the commercial potential of space, the authors document the immense economic and legal hurdles that must be overcome to mine asteroids, beam solar power to Earth's surface, or even develop an orbital phone system (witness the recent bankruptcy of the Iridium satellite network). Yet coming decades will surely see extraordinary advances in the exploration of the solar system by tourists, astronauts, and our mechanical proxies.

Imagining Space is superficial at times, skimming over such potential dynamite as the Nazi origins of America's space technology. It can be somewhat repetitive, and its loopy, we're-destined-for-space introduction by science-fiction doyen Ray Bradbury feels out of place. But the book is beautiful, and it delivers where it counts: You come away feeling wildly impatient to see what will happen next. Corey S. Powell

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