ISSN 0036-8075 5 JUNE 1992 VOLUME 256 NUMBER 5062 AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE 1 3969 1 402, =% 1416 & 1420 RNA makes peptlde bonds and that s not all NEWS & COMMENT Furor at Lyme Disease Conference California Rides Its Own Bi-Cycle Mission Impossible: Saving All Endangered Species Errant HIV Strain Renders Test Virus Stock Useless r 1384 1386 1387 NASA Researchers Protest DOE Turnoff 1388 Panel Clears Needleman of Misconduct 1389 Institute of Medicine Elects New Members 1389 WS........ Scoring a Technical Knockout in Mice r 1392 Researchers Wrestle With Concerns Over Cost and Access Did an Asteroid Leave Its Mark in 1395 Montana Bones? Finding RNA Makes Proteins Gives 1396 'RNA World' a Big Boost Gammas From Heaven 1397 1 392 Knockout mice find & favor with 1 448 biologists PERSPECTIVES New Horizons for RNA Catalysis N. R. Pace On the Other Hand ... G. A. Petsko r 1402 F 1403 ARTICLES Crust Formation and Plate Motion in the Early Archean A. Kroner and P. W. Layer Human Organ Transplantation: Background and Consequences J. E. Murray 1405 1411 DEPARTMENTS THIS WEEK IN SCIENCE EDITORIAL Economic Impact Report 1371 1373 LETTERS 1378 The Smithsonian and Sheep Hunting: R. S. Hoffmann; E. Marshall * European Science: H. W. Mewes, S. Oliver, A. Goffeau; A. Anderson; A. A. Travers, A. Anderson * NIH Leaks: J. Schneider * Fear of Butterflies: A. M. Shapiro - Math Teaching, K-12: Relevant Expertise: S. Mac Lane SCIENCESCOPE 1383 Needles shoot down ADAMHA reorganization, etc. RANDOM SAMPLES 1390 An OTA for Parliament * Parkinson's Progresse Birth Control for Animals, etc. BOOK REVIEWS 1464 A Space for Science, reviewed by D. Serwer * Some Other Books of Interest * Vignettes: Popular Images * Books Received PRODUCTS & MATERIALS 1467 .AAAS Board of Directors- .:Board of Reviewing Editors. Leon M. Lederman Retiring President, Chairman F. Sherwood Rowland President Eloise E. Clark President-elect Mary Ellen Avery Francisco J. Ayala Robert A. Frosch Florence P. Haseltine Alan Schriesheim Jean'ne M. Shreeve Chang-Lin Tien Warren M. Washington William T. Golden Treasurer Richard S. Nicholson Executive Officer John Abelson Frederick W. Alt Don L. Anderson Stephen J. Benkovic David E. Bloom Floyd E. Bloom Henry R. Bourne James J. Bull Kathryn Calame C. Thomas Caskey Dennis W. Choi John M. Coffin Bruce F. Eldridge Paul T. Englund Richard G. Fairbanks Douglas T. Fearon Harry A. Fozzard Victor R. Fuchs Theodore H. Geballe Margaret J. Geller John C. Gerhart Roger 1. M. Glass Stephen P. Goff Corey S. Goodman Stephen J. Gould Ira Herskowitz Eric F. Johnson Stephen M. Kosslyn Michael LaBarbera Charles S. Levings Ill Harvey F. Lodish Richard Losick Anthony R. Means Mortimer Mishkin Roger A. Nicoll William H. Orme-Johnson Ill Stuart L. Pimm Yeshayau Pocker Dennis A. Powers Ralph S. Quatrano V. Ramanathan Erkki Ruoslahti Ronald H. Schwartz Terrence J. Sejnowski Thomas A. Steitz Richard F. Thompson Robert T. N. Tjian Emil R. Unanue Geerat J. Vermeij Bert Vogelstein Harold Weintraub Zena Werb George M. Whitesides Owen N. Witte Keith Yamamoto SCIENCE * VOL. 256 * 5 JUNE 1992 ScIENCE 1368