2/07 New Faces of the Human Past snfi JE» pww" >° laest city UocaOon.^P c the and * of the g 65 ***?*:£ PyranV»d heart f a per l'j L-, .,--^ J LAUD OF THE IMKAS American Museum S Natural History *%J EXPEDITIONS Hidden Caves of the Dordogne & Pyrenees June 12-22,2007 Join renowned AMNH anthropologist lanTattersall to uncover the 1 7,000 year- old glories of the hidden caves of the Dordogne and Pyrenees, spectacularly decorated by Ice Age artists and accessi- ble to a limited number of visitors. Visit Lascaux II as well as several other renowned prehistoric sites, including Cap Blanc, Rouffignac, and the seldom- visited cave of Bernifal. $6,350 land only/per person, double occ. American Museum of Natural History Expeditions Central Park West at 79th Street, New York, New York 10024 Phone: 800-462-8687 or 2 1 2-769-5700 www.amnhexpeditions.org FEBRUARY 2007 VOLUME 116 N UMBER 1 FEATURES COVER STORY 22 FACES OF THE HUMAN PAST Science and art combine to create a new portrait gallery of our hominid heritage. RICHARD MILNER AND IAN TATTERSALL 38 FAMILY TIES Unexpected social behavior 30 EIGHT ARMS, WITH ATTITUDE in an improbable arachnid, Octopuses count personality, playfulness, and practical the whip spider intelligence among their leading character traits. LINDA S. RAYOR JENNIFER A. MATHER ON THE COVER: The hominid species Homo rudolfensis lived in East Africa between 1.8 and 1.9 million years ago. Illustration by Viktor Deak 13 EPARTMENTS THE NATURAL MOMENT Heart of the Matter Photograph by Matthew T. Russell 8 UP FRONT Editors Notebook L 9 LETTERS 10 CONTRIBUTORS 13 SAMPLINGS News from Nature 16 UNIVERSE Little Neutral Ones Neil deGrasse Tyson 46 THIS LAND 55 THE SKY IN FEBRUARY Ozark Mushrooms Joe Rao Robert H. Molilenbrock 58 nature.net 48 BOOKSHELF OfArms and the Brain Laurence A. Marschall Robert Anderson 52 OUT THERE 60 AT THE MUSEUM Not Seeing Is Believing Charles Liu 64 ENDPAPER Small Is Beautiful PICTURE CREDITS: Page 54 Visit our Web site at www.naturalhistorymag.com Truth be told, I'm as financially ambitious as I an socially conscious. WeV we hear you. You want to do good. You also want to do well. That's why we manage Calvert mutual funds with Double Diligence." It's our disciplined process for finding stocks with strong growth potential and avoiding those at risk from unethical business practices. So you can invest for your goals without compromising your values. Keep in mind, investment in mutual funds involves risk, including possible loss of principal invested. 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Calvert mutual funds are underwritten and distributed by Calvert Distributors, Inc., member NASD, a subsidiary of Calvert Croup, Ltd.#6207 (12/06) a UN I Fl company '*$* — — THE NATURAL MOMENT UP FRONT See preceding two pages Hominid Time Machine The year is 3.2 million B.C., the light is flattering, and for once, Og's face isn't covered with blood, grime, and the infected bites of tsetse flies. Doesn't someone have a digital camera? Regretfully, no. And no one, to my knowledge, has unearthed a pinhole image from that luminous day, Revealing your heart to some- inadvertently recorded for posterity on some nearby photosensitive rock. one takes time. In the case of So we're stuck. If today's de- IC 1805—a hot cloud of gas near scendants of Og and his tribe the constellation Cassiopeia—the us—want pictures of our distant revelation has taken 7,500 years. ancestors for the mantel, we have That's how long light from the to make 'em ourselves. Fortu- cloud must travel through space to nately, the project is intriguing reach Earth. But close observers ot enough to attract institutional the sky will find the long-distance support and inspire such long- relationship rewarding: through term organizational discipline even a small telescope, the light that the most talented scientists from IC 1805 makes the pattern and artists in the world find their that inspired the cloud's common way into the field. Meet Gary J. name, the Heart Nebula. Sawyer (near right), Viktor Deak The Heart Nebula owes its (far right), and their friends. color, size, and heart shape chiefly Sawyer is a physical anthro- to a group of young, energetic pologist at the American Mu- stars clustered together in the neb- seum of Natural History in New ula's center. The hot young stars York City; Deak is a paleoartist emit ultraviolet radiation that, in with that rare kind of virtuosity that can blow you away. Richard Milner turn, excites the gas around them. and Ian Tattersall tell the story of their collaboration, and the history ot Most of the excited gas particles their predecessors, in the text that accompanies the extraordinary images are hydrogen ions, so when those you'll find in "Faces of the Human Past" (page 22). ions "relax" and recombine with Yet isn't it presumptuous to suppose that an artist can envision such a free electrons, they throw off their distant past? Deak is explicit about his assumptions. With fossils from just extra energy as deep red light. one side of a face, his renderings are bilaterally symmetric. The underly- Photographer Matthew T. ing facial muscles he at carefully calculated points along the anatomical Russell caught the nebula on a path between contemporary primates and humans. Many of Deak's sub- charge-coupled device rigged to a jects look healthy, well fed, uninjured—artistic license, one might think four-inch refracting telescope this but he points out that modern gorillas are quite careful about their ap- past September, from his personal pearance. Even hair has an empirical basis: its thickness and coarseness observatory in Black Forest, Colo- reflect assessments of diet, activity level, and the role of sexual selection. rado. He tracked the patch of sky- The computer has become a powerful tool: in Photoshop. Deak can to make a five-and-a-half-hour borrow what he wants from scores of images ot contemporary primates, exposure of the nebula, using four cutting and pasting so profligately that a single final image may be made color filters to separate and re- up of 250 digital "layers" and consume a gigabyte on his hard drive. create the nebula's colors. As telescopes of Hubble-like proportion compete in a kind of Even though my editorial colleagues and I are "ink-stained wretches." technological arms race in space devoted to Natural History as a print magazine, we understand that programs around the globe, many readers today are informed and entertained through many other Russell's photograph proves that media. So won't you please write and tell me what you'd most like to see the backyard telescope still has us add to our Web site? Take a look at the current site (www.naturalhistory amazing potential, too. After all. mag.com) and then send your thoughts and suggestions to me by e-mail who said you have to be big to at [email protected], or by mail at: Natural History Web Site. capture a heart? —Erin Espelie 36 West 25th Street, fifth floor.