Excavations at a remarkably ornate Maltese grave site yield a much more complicated picture of these prehistoric beliefs.Ĭurrent Events Philip Yam, staÝ writer When the hype about high-temperature superconductors faded and Washington bureaucrats turned their attention to other high-profile matters, workers began making quiet progress. The Death Cults of Prehistoric Malta Caroline Malone, Anthony Bonanno, Tancred Gouder, Simon Stoddart and David Trump The statues of obese female Þgures found in ancient Mediterranean settlements have provoked speculation about fertility cults and goddess-centered protoreligions. The same mathematical principles that describe this phenomenon also apply to the synchrony of fireflies flashing in a tree or the fiber bundles that regulate a heart. When two pendulum clocks stand on a surface, Christiaan Huygens discovered, their pendulums will eventually beat in unison. 10017-1111, or fax : (212) 355-0408.Ĭoupled Oscillators and Biological Synchronization Steven H. Reprints available: write Reprint Department, Scientific American, Inc., 415 Madison Avenue, New York, N.Y. Postmaster : Send address changes to Scientific American, Box 3187, Harlan, Iowa 51537. and possessions add $11 per year for postage). Subscription rates: one year $36 (outside U.S. Authorized as second-class mail by the Post Office Department, Ottawa, Canada, and for payment of postage in cash. Second-class postage paid at New York, N.Y., and at additional mailing offices. No part of this issue may be reproduced by any mechanical, photographic or electronic process, or in the form of a phonographic recording, nor may it be stored in a retrieval system, transmitted or otherwise copied for public or private use without written permission of the publisher. Copyright © 1993 by Scientific American, Inc. Scientific American (ISSN 0036-8733), published monthly by Scientific American, Inc., 415 Madison Avenue, New York, N.Y. Powerful computers and detailed knowledge of the chemical structure of drug targets may enable researchers to create an image of such a target and then work backward to design an appropriate therapeutic molecule. The future of drug development may take shape differently. Montgomery Random discovery deserves the credit for many of the important pharmaceutical agents in use today. Campaigns of breeding with gentler strains offer hope of success.ĭrugs by Design Charles E. Their propensity for vigorous hive defense, celebrated in print and Þlm, as well as the menace they constitute to the beekeeping industry, makes control desirable. Africanized honeybeesÑdescendants of bees brought to Brazil from Africa in 1956Ñhave now spread into the U.S. Sheppard TheyÕre here, and not just at the local cinema. There were many Adams and Eves.Īfricanized Bees in the U.S. Ayala Analysis of the major histocompatibility complex locus, which governs the recognition of self by the immune system, reveals two profound surprises concerning the evolution of humans: the immune system is much older than the species that it protects, and the ancestral population must have been large, not small. MHC Polymorphism and Human Origins Jan Klein, Naoyuki Takahata and Francisco J. As a result, the textbooks in astrophysics are being rewritten. Now workers can observe the radioactive remnants of exploded stars, the cores of active galaxies and other exotic objects that emit gamma radiation. But until the Compton Gamma Ray Observatory was launched, the gamma-ray sky was largely oÝ-limits. Kurfess and Volker Schšnfelder Gamma rays emanate from the hottest, most violent cosmic events. The Compton Gamma Ray Observatory Neil Gehrels, Carl E. Access to contraception as well as changes in cultural values and education has caused fertility to decrease there. But surveys in Third World nations have shown that economic improvement is not a necessary precondition of falling birth rates. At least that is the way it happened in many Western countries. Rutstein and Leo Morris As prosperity increases, family size declines and a population achieves stable size. The Fertility Decline in Developing Countries Bryant Robey, Shea O. Using computers to design drugs.Ĭolliding neutron stars unleash a burst of energetic radiation visible from across the universe.
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