American Museum S Natural History ^ Worlds to Discover... AMNH Expeditions Family Programs Set out on an adventure for the entire family with AMNH Expeditions— fly a kite in Tiananmen Square; snorkel with playful Galapagos sea lion; enjoy a scavenger hunt in the ancient Athenian Agora. Members and friends of the Museum have been exploring the world on AMNH Expeditions for more than 50 years in the company of AMNH scientists and guest lecturers. Our diverse lineup of Family Programs is designed to engage, enrich, and delight all generations. For a complete listing of our upcoming Family Programs and to book online, visit our website at amnhexpeditions.org or call AMNH Expeditions at 800-462-8687 or 212-769-5700 MARCH 2007 VOLUME 116 NUMBER 2 COMMENTARY 38 BAD NEWS FOR BEARS This fall, despite a public outcry, bears habituated to people in Alaska's McNeil sanctuary may be hunted on adjacent lands. BILL SHERWONIT FEATURES 52 BAR CODING FOR BOTANY A system )nodeled o)i commercial bar codes may soon enable anyone to identify any plant from a smallfragment of its DNA. KENNETH M. CAMERON COVER STORY 58 ON THE TRAIL OF THE ANCESTORS AnaSii:i pueblos lie in ruins across the American Southwest. ]]lhn bccanic of their iiihabitains? CRAIG CHILDS ON THE cover: Doonvav, with kiva and roof entrance, Mesa Verde National Park, Colorado. Photograph by George H.H. Huey HfVM DEPARTMENTS 4 THE NATURAL MOMENT Exit Strategies Photograph by Tony Martin 6 UP FRONT 64 BOOKSHELF Editor's Notebook ^ Laurence A. Marschall 8 CONTRIBUTORS % 68 OUT THERE 9 LETTERS Spin Control Charles Liu 74 nature.net ^Tf New Tubes Robert Anderson 75 THE SKY IN MARCH Joe Rao 76 EXPLORING SCIENCE 64 AND NATURE 80 ENDPAPER Notes from the Edge Robert R. Dunn 11 11 SAMPLINGS News from Nature 14 PERSPECTIVES Ice Cycles Donald Goldsmith 36 BIOMECHANICS No Bones About 'Em Adam Summers 36 PICTURE CREDITS: Page 8 Visit our Web site at www.naturalhistorymag.com He was a hardworking farm boy. She was an Italian supermodel. He knew he would have just one chance to impress her. Rosetta Stonef The fastest and easiest way to learn iTAUAN Korean Polish Spanish Swedish Turkish Arabic Dutch Farsi Greek Indonesian ( Chinese English(UK) French Hebrew Italian Latin Portuguese Spanishc Tagalog Vietnamese Danish English(usi German Hindi Japanese Pashto Russian Swahili Thai Welsh Learn a language. Expand your world. Finally, there's a way to learn a new language that's easier than you could ever imagine. Rosetta Stone interactive software teaches you any of 30 languages, all without translation, memorization, or grammar drills. 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Regularly $^55:60 Regularly $gg5. 00 Regularly $02 9 .00 NOW $175.50 NOW $202.50 NOW $296.10 The fastest way to learn a language. Guaranteed RosettaStone Language Learning ^K^^ Success 1-800-399-6162 RosettaStone.com/nhs037 Use promotional code nhs037 when ordering. THE NATURAL MOMENT Exit Strategies Photograph by Tony Martin 4 NAT;.i<AL HISTORY March 2007 '^' nv THE NATURAL MOMENT UP FRONT See preceding two pages Killer App Kenneth M. Cameron ("Bar Coding for Botany," page 52) imag- ines that one day soon, "global flora scanners" will catch bad guys who smuggle endangered plants across international bor- ders. My vision is more benign: You've taken the day off to hike the Even from across a field of sea woods in the early spring. Wet snow still fills the forest with cool, damp ice crowded with emperor air, but the sun is bright, and up ahead, at a break in the canopy, a blos- penguins, Tony Martin was startled som is bravely forcing the new season. The flower is unfamiliar. when he spotted a lone Weddell You unclip your handheld GFS unit from your belt. Stoop. Snip. You seal shoot through what looked like take a tiny bite of leaf with the hole punch, press "ID" on the keypad, soUd ice. Martin, a zoologist with and wait for the Hypernet response. Sure enough, the blossom is a rare, the British Antarctic Survey, began endangered blue-eyed Mary (Collinsia verna); no one has recorded the walking toward whatever crack or flower in these woods for twenty years. Immoderately pleased by your hole had allowed the seal to emerge sharp eyes and good luck, you press "Record"; the system clock marks from the Ross Sea below. Before he the time and date, the GPS module remembers the location, and the arrived, the seal slid back under the flower is filed in your personal database. Before you move on, you take ice, leaving Martin to wait. a digital photograph of the flower, and dictate a few remarks into the The portal proved to be about digital recorder. three feet across, its inner edges Behind this new technological magic is one of the most exciting serrated from the gnawing of the biological projects since the sequencing of the human genome. The seals' front teeth, a process known project, known as DNA bar coding, is an international effort to create as reaming. In the summer months a universal genetic database of life by sequencing short, species-specific intense reaming isn't needed, be- regions of DNA from every living species on Earth. Among botanists, cause the ice is thinner and has Cameron says, the goal is to identify two or perhaps three genes that more natural openings the seals occur in all plants, yet in combination are distinctive enough from spe- can use to surface. But whether cies to species to serve as reliable species markers. Between now and an under thick or thin ice, Weddells international meeting this September in Taiwan, of the Consortium for are far from hindered under water: the Barcode of Life (CBOL), Cameron and his colleagues in the Plant they can sleep, mate, or, most Working Group are seeking as much peer review as possible before a often, hunt for fish and squid. recommendation is made about exactly which genetic markers will On a hunt, Weddells can descend serve as bar codes in the database. a quarter of a mile under water and How long wiU it take to build the database? "Lots of people are hold their breath for more than an chomping at the bit to get into this," Cameron says. The bar codes for hour. On such dives the seals slow the vast majority of land plants could be ready within a couple of years their hearts, decrease blood flow, of CBOL's decision, he adds. At the same time, electronics and nanotech- and use oxygen stored in their nology circles are buzzing about how the relevant bar codes would be muscles. Physiologists dream that "read" in the field. Presumably, Cameron explains, once the plant matter genes for low-oxygen tolerance is sampled and dissolved, its DNA would be channeled along micro- might one day help treat people etchings on a chip-size glass surface, where a sequence of miniature with heart and lung diseases. chemical reactions and embedded logic circuitry would look for the Martin experienced the seals' relevant genes. No one knows how long Silicon Valley will need to make diving stamina firsthand, as he a usable product, but given the pace of change, several electronic genera- waited at the lip of the hole. After tions (that is, five or ten years) doesn't seem unreasonable. an hour of keeping vigil, he got a big surprise when a 500-pound seal launched itself out of the water Our regular "Biomechanics" columnist, Adam Summers, reaches a "like a missile out of a submarine," milestone with this issue. His column, "No Bones About 'Em" and landed on top of him. Fortu- (page 36), about the advantages of having a cartilaginous skeleton, is his nately, the next seal to come up for fiftieth for Natural History. That's a remarkable achievement for a scien- air simply poked out its deceptively tist and professor stiU young enough to have a seven-month-old child at petite head. —Erin Espelie home. 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