Science  20 Jul 2001:
Vol. 293, Issue 5529, pp. 399

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  1. EXHIBITS: Meet a Fossil Pioneer

    He's the most important paleontologist you've never heard of. In the mid-1800s, when European paleontologists dismissed their American colleagues as yokels, Joseph Leidy proved otherwise with his meticulous studies of vertebrate fossils pouring in from the West. Among other things, Leidy showed that horses roamed North America long before the Spanish conquest and that the continent was once home to enormous ground sloths. This online exhibit from the Philadelphia Academy of Natural Sciences uncovers the life and work of local hero Leidy (1823–91). The site includes lithographs of fossils from some of the pioneering paleontologist's more than 230 publications and summaries of his treatises on dinosaurs, mammals, and other extinct vertebrates. The modest and cautious scientist was appalled by the slapdash science and egocentric antics of the “bone wars” between rivals Othniel Marsh and Edward Drinker Cope, one of Leidy's protégés. So Leidy withdrew from paleontology to spend the rest of his career with some more wholesome characters—parasites.

  2. FUN: Let Your Hair Down

    Brush up on hair science at this fun site sponsored by French beauty products manufacturer L'Oréal. You can find facts even your hairdresser doesn't know by combing through pages on hair growth, structure, color, and ethnic differences. For example, hair doesn't actually turn gray as we age; it loses pigment, which causes it to appear grizzled. Other pages explain what scientists can deduce by analyzing the composition of hair. (Napoleon was probably poisoned with arsenic, and Beethoven didn't die from syphilis.) The site also plucks some revealing close-ups. Victims of split ends, take heart: Even the most lustrous locks appear gnawed under the microscope.

  3. DATA: Who's the Fastest One of All?

    And they're off—competitors from around the world are racing to build the most powerful supercomputer. Keep tabs on their progress at TOP500, maintained by the University of Mannheim in Germany and the University of Tennessee, Knoxville. The site ranks the top 500 high-performance supercomputers based on their speed in crunching a set of hairy linear equations. IBM may have lost out in the PC market, but it claims six of the leading 10 slots in the latest supercomputer rankings. The winner, a 8192-processor system used for simulating nuclear explosions at the Lawrence Livermore National Laboratory in Livermore, California, clocks in at more than 12 trillion operations per second, 20,000 times faster than a PC. The computer experts behind TOP500 have been running time trials since 1993 and publish updated rankings every 6 months.

  4. IMAGES: NASA's Photo Album

    Spanning more than 50 years of space exploration, this gallery brims with over 1000 high-resolution images from NASA's archives, from black-and-white pictures of early rocket and airplane tests to recent stunners of colliding galaxies snapped by the Hubble Space Telescope. Besides beautiful shots, the offerings include photos of famous figures—such as rocket pioneer Wernher von Braun, a former German SS officer who masterminded manned flights to the moon—and momentous occasions, like astronaut Neil Armstrong standing on the moon in 1969.

  5. EDUCATION: The Bugs That Run the World

    They're more powerful than Alan Greenspan, George W. Bush, or even Madonna. Microbes hold sway over such vital planetary matters as the composition of the atmosphere and the productivity of ecosystems. The Microbial World, an educational site designed for students in beginning microbiology courses, teems with information on the ecological importance of bacteria and fungi, the specialty of site founder Jim Deacon of the University of Edinburgh in Scotland. The content covers more than 35 specific topics—from Dutch elm disease, to airborne bacteria, to efforts to produce a natural pesticide from the soil bug Bacillus thuringiensis. You can also take a virtual trip to microbial hangouts like Yellowstone Park's hot springs.