Mapping Human History:
Discovering the Past Through Our Genes
By Steve Olson
Houghton Mifflin, $25
The Molecule Hunt:
Archaeology and the Search for Ancient DNA
By Martin Jones
Arcade Publishing, $26.95
One of the things that turned Jurassic Park
into a blockbuster in 1993 was that it seemed possible. The technology for grabbing pieces of DNA and reading their sequences was just getting up to speed. Maybe, just maybe, if you found a piece of amber that contained a mosquito that had sucked the right drop of blood 70 million years ago, you could isolate the genes of Tyrannosaurus rex.
By the time Jurassic Park II
came out in 1997, scientists realized that cloning a dinosaur is pure fantasy, because we cannot recover DNA more than a few hundred thousand years old. But genetic forays into the more recent past have yielded a stunning consolation prize: DNA—from fossils and living organisms—is rendering obsolete the standard textbook version of human origins and the rise of civilizations.
Martin Jones's The Molecule Hunt
and Steve Olson's Mapping Human History
offer different but complementary accounts of this revolution. Jones, an archaeologist at Cambridge University, surveys dozens of examples of how DNA (as well as proteins, fatty acids, and other organic molecules) has radically changed the nature of his work. Where archaeologists once had only sherds of pottery for clues to a vanished people, they can now get information about the biology of the humans who made the pottery. They can study the DNA of the animals and crops those humans raised and even the pathogens that made them sick. Moreover, Olson contends that understanding the ancient history gleaned from DNA bears directly on two of the world's hot-button issues: race and ethnicity. His book demonstrates just how naive some of our ideas about our human ancestry have been.
One example: Many paleontologists argued that Neanderthals were the forerunners of living Europeans. But that was before geneticists isolated DNA more than 30,000 years old from Neanderthal fossils found in Germany, Croatia, and the Caucasus Mountains. DNA acts like a genealogical bar code: If you are born with some distinctive mutation, you can pass it down to your descendants. With the aid of such mutations, scientists can extrapolate genetic changes through time and group individuals together on different genealogical branches. If the old hypothesis were right, the DNA of living Europeans would have been similar to that of Neanderthals. But Europeans' DNA is actually much more similar to that of Asians and Africans. The evidence supports a growing consensus that the ancestors of Neanderthals and living humans split into separate lineages some half-million years ago, then evolved into distinct species. Their species died out, whereas ours survives.
Today our species is 6 billion strong around the globe. But the prevailing view among human-origins experts is that only 100,000 years ago our ancestors consisted of just a few thousand individuals who all lived somewhere in eastern Africa. The DNA record now allows scientists to parse the epic migration of humans through the ages into distinct waves of immigration, invasion, and assimilation. It turns out that we have been raised on archaic notions of our origins—both as a species and as distinct ethnic groups. The scattered descendants of the ancient Israelites, for example, can still be genetically recognized today as far away as southern Africa. But that doesn't mean there is anything like a Jewish race—or any other race for that matter—in a biologically meaningful sense of the word. The genetic variation within every human population is enormous, much more than the variation between populations. As Olson points out, the racial mixing in recent history is not entirely new; genes have been crossing borders and oceans for thousands of years.
Yet we still cling to outmoded ideas of race to define ourselves and our connection to the past. In 1996, when the skeletal remains of the 9,500-year-old Kennewick Man turned up in Washington State, several groups scrambled to claim him as an ancestor. Local Indian tribes wanted to bury him in proper fashion as one of their own. Researchers, however, discovered that Kennewick Man had features more like those of a Caucasoid; other scientists, meanwhile, had found DNA sequences in certain Indian tribes that hinted of an ancient link with European populations. The scientists sued to stop the transfer to the Indians so that their study of Kennewick Man's bones could continue. An obscure religious sect that worships the Viking gods also filed suit to stop the transfer of Kennewick Man. But early results of DNA analysis suggested he might be related to Southeast Asians. Last July a Polynesian chief entered the fray, claiming to be a direct descendant of Kennewick Man and asserting his right to bring his ancestor back home to the Pacific.
For all who would call Kennewick Man their own, Olson offers some good news and some bad news. It is possible that the California Vikings do indeed descend from him. It is possible that the members of Washington's Indian tribes descend from him as well. It is also possible that the Polynesian chief descends from him. And so could you. Statisticians have shown that the world's genealogies do not reach back through time in distinct lines but are instead hideously tangled. The majority of people who were alive several thousand years ago could be direct ancestors of all 6 billion people alive today. Concepts like race and ethnicity continue to tear people apart, but our common DNA shows how closely related we all are. The struggle for Kennewick Man's bones ignores the reality that he may well be a great-grandfather to us all. Books Bigger Than Life
A mammoth book of lush illustrations documents a host of natural curiosities from a simpler time By Margaret Foley Albertus Seba—Cabinet of Natural Curiosities
Text by Irmgard Müsch, Rainer Willmann, and Jes Rust
One way for an 18th-century man to further—and flaunt—his erudition was to assemble his own cabinet of curiosities, containing everything from dried plants to pickled pythons. The Dutch apothecary Albertus Seba amassed a collection of natural species so spectacular that students and scholars from all over Europe traveled to his home in Amsterdam to view drawers filled with such rarities as butterflies from New Guinea and preserved reptiles from Japan and India. Even the Russian czar Peter the Great stopped by one day and eventually acquired Seba's early collection, a smaller precursor to the apothecary's renowned trove. Albertus Seba—Cabinet of Natural Curiosities
is a glorious 17-pound 171/2-by-12-inch tome packed with reproductions of all 446 illustrations Seba commissioned for his collection's Thesaurus,
which was published in four separate volumes between 1734 and 1765. Seba's Thesaurus
was originally printed in black-and-white, but this reprint has been reproduced from a hand-colored edition housed in the Royal Library, The Hague. The illustrations range from apparently faithful renderings of cone shells to an apocryphal visualization of a seven-headed hydra. Many specimens are depicted not as they appeared in Seba's collection but as they were believed to have appeared in life; his illustrators most likely worked with decayed specimens and limited documentation. As a result the collection of illustrations is populated with coy deer, sly-looking possum, joyful bats, and other mammals bearing near-human facial expressions. Moreover, subjects are artfully arranged on the pages, with little regard for scale, so that a huge slithering grass snake dwarfs a giant anteater.
Although the illustrations often confound the factual with the fantastic, Seba's Thesaurus
endures as a grand and wondrous visual record of science at a crossroads. As the century progressed, the expanding breadth of scientific knowledge and the increasing use of the microscope transformed the study of the natural world from an avocation to true science. Although Carl Linnaeus, an 18th-century Swedish botanist, consulted the Thesaurus
while devising his system of taxonomy, the evolution of a more rigorous approach to the nascent field of biology and the demand for more scrupulous detail in scientific renderings eventually turned Seba's idiosyncratic work into little more than a historical curiosity. Yet that same idiosyncrasy now fascinates, exposing the human need— imperfectly realized—to control, categorize, and make sense of an unfamiliar, changing world. Television Red Gold: The Epic Story of Blood
Premieres on PBS Sunday, June 23,
9 p.m. eastern time
The first documented blood transfusion occurred in 1667, when a French experimenter pumped calf's blood into a madman. Although the patient survived, the practice challenged religious beliefs regarding the sanctity of blood and was soon outlawed, only to be revived in 1818 when an English physician transfused human blood into a woman dying in childbirth. The transfusion "successfully reanimated" her, he wrote, and similar experiments continued.
Such historical anecdotes abound in Red Gold,
a four-hour PBS documentary presented in four installments that chronicles the discovery of lifesaving transfusion therapies and the gradual emergence of blood as a commercial commodity. The first episode is marred by some cheesy historical reenactments, including the death of George Washington from repeated bloodlettings. But the subsequent episodes offer a fascinating glimpse of the intersection of politics, business, and medicine. For instance, in one sequence the filmmakers recount the story of Charles Drew, an American physician who headed Britain's plasma program in World War II but was legally barred from donating his own blood in the United States because he happened to be African American.
Ironically, the battlefields of the 20th century produced the key innovations that made transfusions a ubiquitous tool of modern medicine: refrigerated storage containers and chemical treatments to preserve blood and its components. Improvements in blood banking and plasma storage also gave rise to a surging commercial interest in paid donors, who were solicited first for whole blood and later for plasma, the component of blood most easily stored and transported. A notorious blood donation center in Managua, Nicaragua, reputedly jeopardized the health of impoverished donors by drawing blood far more often than is safe; reports of that abuse helped fuel the popular resistance that toppled the dictatorial regime of Antonio Somoza in 1979. Not long afterward, a different sort of scandal emerged in countries around the world: the contamination of blood products by blood-borne pathogens—first hepatitis and then HIV. Beginning in 1980, more than 8,000 hemophiliacs in the United States contracted HIV through transfusions; 6,000 of them died.
Donated blood is now routinely screened through at least eight different tests, and although blood-bank donors are no longer paid, the price of processing a unit of blood has risen from $50-$60 in the 1970s to $135 today. In this cautious climate, hospitals face daunting shortfalls. In India supplies are so low that surgery patients must solicit relatives for blood. Even in the United States, few people donate blood regularly, and increasingly stringent screening for risk factors has narrowed the pool of eligible donors. New York City, for example, imported up to one-third of its blood supply from Europe in the 1990s. But fear that mad cow disease could spread through the blood supply may trigger a ban on blood imported from Europe.
And so the story continues. As Red Gold
urgently reminds us, the lifesaving abundance running through our veins still remains a precious—and fragile—commodity.
(Editor's note: See also The Chemistry of . . . Blood
, page 20.)— Sarah Richardson Toys
|Soccer Jr. uses three motors and 17 gears to move its feet and paddle. There is no gearing for headers.|
Photograph courtesy of Jens Mortensen
Soccer Jr., $44.95,
Soccer Pro, $44.95,
AIBO ERS 31L, $599
This year, robotics aficionados will use the occasion of the world cup soccer tournament to once again stage a special sideshow: RoboCup. The international competition, held in Fukuoka, Japan, this year from June 19 to June 25, features teams of soccer robots that come in various shapes and range in height from 9 to 32 inches. The goal of RoboCup is to push the pace of robot evolution. But some new off-the-shelf kits will allow you to experience the challenges and triumphs of robotic soccer without leaving home. Two soccer robots from OWI (www.owirobot.com
) can each be assembled with relative ease in a couple of hours and then set into motion using a handheld wired control device. The six-inch-long Soccer Jr. lurches along on six legs and uses a spinning paddle to scoop in the ball and then fling it about six inches away. The five-inch-long wheeled Soccer Pro is faster and more maneuverable, but its two vertical, parallel rollers that pull the ball into a central cavity, then spin outward to kick it, are less powerful than the Jr.'s paddle. Sony's AIBO ERS 31L (www.aibo.com
) is a much more elaborate robot, a cousin of the soccer dogs that actually compete in one RoboCup league. A sophisticated onboard artificial intelligence program lets AIBO respond to voice commands. In addition, a camera mounted in the mouth and a distance sensor in the nose help it detect a three-inch bright-pink ball. If you tell AIBO to "kick the ball," microphones in its ears pick up the command, and a little light protruding from its head shines white. If it shoves the ball with its front foot, and you say "Good AIBO!" and press down gently on its head, the light glows green. AIBO will only nudge the ball with its head at first, then gradually learn to use its foot to kick. But be warned: Occasionally, this four-legged robot ignores commands altogether until you shake its paw or pet it. — Fenella Saunders ScienceBest-sellers
We also like...The Character of Cats:
|1. ||The Universe in a Nutshell |
By Stephen Hawking,
|2. ||The Structure of Evolutionary Theory|
By Stephen Jay Gould,
Harvard University Press
|3. ||The Future of Life |
By E. O. Wilson,
|4. ||The Theory of Everything: The Origin and Fate of the Universe |
By By Stephen Hawking,
New Millennium Press
|5. ||Our Posthuman Future: Consequences of the Biotechnology Revolution|
By Francis Fukuyama,
Farrar, Straus & Giroux
|6. ||How to Build a Time Machine|
By Paul Davies,
|7. ||Cradle to Cradle: Remaking the Way We Make Things|
By William McDonough and Michael Braungart,
North Point Press
|8. || Tuxedo Park: A Wall Street Tycoon and The Secret Palace of Science That Changed the Course of World War II |
By Jennet Conant,
Simon & Schuster
|9. ||How the Universe Got its Spots: Diary of a Finite Time in a Finite Space |
By Janna Levin,
Princeton University Press
|10. ||Six Easy pieces & Six Not So Easy Pieces|
By Richard Feynman,
|* Source: Barnes & Noble Booksellers|
The Origins, Intelligence, Behavior,
and Stratagems of Felis Silvestris Catus
Budiansky pays scientific homage to common house cats by exploring their genetic connection to wild cats, as well as the evolutionary roots of their famously independent behavior. Cradle to Cradle: Remaking the Way We Make Things
William McDonough and Michael Braungart
North Point Press, $25
McDonough, an architect, and Braungart, a former Greenpeace chemist, present a plan for eliminating environmental waste by creating such products as books printed on synthetic paper and running shoes made with reusable plastics. Prime Mover: A Natural History of Muscle
W. W. Norton, $25.95
Vogel traces the evolution of muscles and reveals how tools and weapons, ranging from the simple corkscrew to the more complex catapult, were designed to enhance and mimic muscle power. Storms from the Sun:
The Emerging Science of Space Weather
Michael J. Carlowicz and Ramon E. Lopez
Joseph Henry Press, $27.95
Carlowicz, a journalist, and Lopez, a physics professor, argue that learning to cope with solar explosions that pummel Earth with electrified gas will be crucial to keeping such vital networks as air traffic control and 911 systems up and running.
— Maia Weinstock